Homebrew_PCBs

 

In searching for a vendor of Liquid-Tin I ran across
this waterproofing spray:
http://bamtech.com/product/acrylic-coating/

Since I live in the RustBelt and know what oxidized
copper looks like, I wonder if I should use this on
my PCB to keep the copper from contacting moist air?

Some protection will be smart.

My PCB will be used outside in a plastic box.   The
plastic box will be waterproof, but not airtight.
I am guessing the Liquid Tin and leaded solder  ap-
plied to the traces will prevent oxidation.   I just

No, tin will just change the type of oxide.  Tin oxidizes too. 

want to know if anybody has had experience with this
product or, if my thinking is wrong.

Has anybody used this product on a copper PCB used
outdoors?  If yes, would you recommend it?   Or
would something cheaper like this
http://www.sherwin-williams.com/home-builders/products/catalog/krylon-indooroutdoor-lacquer-spray-paint/?referringCategory=interior-paint-coatings/aerosols/&N=1568189400
work just as well?

Just about any clear acrylic will adhere to clean copper and FR4 and it's variants.

Tin plate enhances solderability, and oxidized tin is generally easier to clean and make solderable.

-- 
mailto:lists@...     http://www.n1oz.net       ARS: N1OZ
Rich Osman;  POB 93167; Southlake, TX 76092 (Near DFW Airport) 

Alan,

There are two issues here. The first is oxidation of the copper, and the second is operation out of doors. If your only issue is oxidation of copper, then don't worry about it. It looks ugly, but as far as I know, it is self limiting.

A larger problem, and the reason why military and automotive hardware uses conformal coat on their boards is condensation.  In some ways, the better the ventilation in the box, the less of an issue this is. Small drain holes on the bottom of the box would be a good idea, unless the box is subjected to spray.  Condensation on your circuit board will cause upset of circuit operation in many cases.  Certainly, in analog circuits, the unexpected conductive paths caused by condensation will alter performance, possibly leading to catastrophic failure.  Digital circuits are less sensitive, but will ultimately be affected, particularly if the signals are very low level.

Conformal coats come in a variety of types, Acrylic, Polyurethane and Silicones, to mention the most popular types.

Krylon is an acrylic material. I have not used it because I worry about how long it will adhere to the board under the outdoor conditions. I have used Polyurethane successfully.  It was not a material designed for use as a conformal coat, as they are very expensive, and hard to get in small quantities. I used a spray material that is suitable for touch up on furniture finishes. At this point, I can't remember the name. Silicones fall into an entirely different category. They are more difficult to use. They usually need a primer, which is another step in the process.

In terms of repairability, the acrylics have it over the others. They are easily chemically removed, and another spray after repair finishes the job. Polyurethane is a killer to remove. Chances of doing damage are very high.  The method of removal is physical, with a good chance to damage surrounding circuit elements. Silicones can be removed by cutting and scraping. Don't be tempted to use the silicone material they sell at your local home supply store.  Silicone sealers, not made for the specific purpose of contact with electronic circuits use an acetic acid cure. This is why they smell like vinegar.  These sealers will eventually attack the copper on your circuit board.

All that said, for me, I would skip the Krylon and go with the Polyurethane furniture spray. A word of caution: Keep your coating thin and if your circuit board uses glass diodes, make sure they are lifted a bit off the board, so that the coating does not stick the part to the board. I have seen diodes crack because the coefficient of thermal expansion of the board is much greater than that  of the glass component.

Harvey

 

In searching for a vendor of Liquid-Tin I ran across
this waterproofing spray:
http://bamtech.com/product/acrylic-coating/

Since I live in the RustBelt and know what oxidized
copper looks like, I wonder if I should use this on
my PCB to keep the copper from contacting moist air?

My PCB will be used outside in a plastic box.   The
plastic box will be waterproof, but not airtight.
I am guessing the Liquid Tin and leaded solder  ap-
plied to the traces will prevent oxidation.   I just
want to know if anybody has had experience with this
product or, if my thinking is wrong.

Has anybody used this product on a copper PCB used
outdoors?  If yes, would you recommend it?   Or
would something cheaper like this
http://www.sherwin-williams.com/home-builders/products/catalog/krylon-indooroutdoor-lacquer-spray-paint/?referringCategory=interior-paint-coatings/aerosols/&N=1568189400
work just as well?

>
> On 7/30/2016 10:34 AM, alan00463@... [Homebrew_PCBs] wrote:
>>
>> In searching for a vendor of Liquid-Tin I ran across
>> this waterproofing spray:
>> http://bamtech.com/product/acrylic-coating/
>>
>> Since I live in the RustBelt and know what oxidized
>> copper looks like, I wonder if I should use this on
>> my PCB to keep the copper from contacting moist air?
>>
> Some protection will be smart.
>>
>>
>> My PCB will be used outside in a plastic box. The
>> plastic box will be waterproof, but not airtight.
>> I am guessing the Liquid Tin and leaded solder ap-
>> plied to the traces will prevent oxidation. I just
>>
> No, tin will just change the type of oxide. Tin oxidizes too.

Brad,

You are correct about the whiskers, but the conformal coat will not stop them. The whiskers will punch through the coating, and if two conductors are close enough, their respective whiskers can contact. I would stay away from tin, if at all possible.

The conditions that lead to whisker growth are not understood. They don't need extreme outdoor conditions, nor moisture, nor even air to initiate or grow. A lot of money has been thrown at this problem, and still there is no understanding of the basic physics of this phenomenon. Unfortunately, a lot of DIP package ICs were manufactured with tin platings on their leads.  Solder dipping right up to the body eliminates the threat, but may cause other damage. Newer packages use other platings that are not susceptible to whiskering.

Harvey

 

On 7/30/2016 11:43 AM, Rich Osman lists@... [Homebrew_PCBs] wrote:
>
> On 7/30/2016 10:34 AM, alan00463@... [Homebrew_PCBs] wrote:
>>
>> In searching for a vendor of Liquid-Tin I ran across
>> this waterproofing spray:
>> http://bamtech.com/product/acrylic-coating/
>>
>> Since I live in the RustBelt and know what oxidized
>> copper looks like, I wonder if I should use this on
>> my PCB to keep the copper from contacting moist air?
>>
> Some protection will be smart.
>>
>>
>> My PCB will be used outside in a plastic box. The
>> plastic box will be waterproof, but not airtight.
>> I am guessing the Liquid Tin and leaded solder ap-
>> plied to the traces will prevent oxidation. I just
>>
> No, tin will just change the type of oxide. Tin oxidizes too.

Hello--

Worse yet, tin can grow conductive whiskers that can cause short
circuits and intermittents:

http://nepp.nasa.gov/whisker/reference/tech_papers/2012-Panashchenko-IPC-Art-of-Metal-Whisker-Appreciation.pdf

There's information on what conformal coatings NASA found that would
resist whisker growth.

The waterproof box will collect moisture inside due to infiltration of
moist air and temperature cycling.
About all one can do is to create an air- and water-tight box that has a
moisture-accumulating
dryer cartridge venting the box. You'd have to periodically replace the
cartridge.

73--

Brad AA1IP

>Brad,
>
>You are correct about the whiskers, but the conformal coat will not stop
>them. The whiskers will punch through the coating, and if two conductors
>are close enough, their respective whiskers can contact. I would stay
>away from tin, if at all possible.
>
>The conditions that lead to whisker growth are not understood. They
>don't need extreme outdoor conditions, nor moisture, nor even air to
>initiate or grow. A lot of money has been thrown at this problem, and
>still there is no understanding of the basic physics of this phenomenon.
>Unfortunately, a lot of DIP package ICs were manufactured with tin
>platings on their leads. Solder dipping right up to the body eliminates
>the threat, but may cause other damage. Newer packages use other
>platings that are not susceptible to whiskering.

>
>Harvey
>
>
>On 7/30/2016 12:08 PM, Brad Thompson brad.thompson@...
>[Homebrew_PCBs] wrote:
>>
>>
>>
>> On 7/30/2016 11:43 AM, Rich Osman lists@... [Homebrew_PCBs] wrote:
>> >
>> > On 7/30/2016 10:34 AM, alan00463@... [Homebrew_PCBs] wrote:
>> >>
>> >> In searching for a vendor of Liquid-Tin I ran across
>> >> this waterproofing spray:
>> >> http://bamtech.com/product/acrylic-coating/
>> >>
>> >> Since I live in the RustBelt and know what oxidized
>> >> copper looks like, I wonder if I should use this on
>> >> my PCB to keep the copper from contacting moist air?
>> >>
>> > Some protection will be smart.
>> >>
>> >>
>> >> My PCB will be used outside in a plastic box. The
>> >> plastic box will be waterproof, but not airtight.
>> >> I am guessing the Liquid Tin and leaded solder ap-
>> >> plied to the traces will prevent oxidation. I just
>> >>
>> > No, tin will just change the type of oxide. Tin oxidizes too.
>>
>> Hello--
>>
>> Worse yet, tin can grow conductive whiskers that can cause short
>> circuits and intermittents:
>>
>> http://nepp.nasa.gov/whisker/reference/tech_papers/2012-Panashchenko-IPC-Art-of-Metal-Whisker-Appreciation.pdf
>>
>> There's information on what conformal coatings NASA found that would
>> resist whisker growth.
>>
>> The waterproof box will collect moisture inside due to infiltration of
>> moist air and temperature cycling.
>> About all one can do is to create an air- and water-tight box that has a
>> moisture-accumulating
>> dryer cartridge venting the box. You'd have to periodically replace the
>> cartridge.
>>
>> 73--
>>
>> Brad AA1IP
>>
>>

>I use leaded solder too, Harvey. W. Which is why I wash my hands after soldering before eating.

> From what I know, regular tin plating is not a problem. Mostly tin
> solder is. How long this whisker growth takes I do not know, a rough
> suspicion (and that's all it is) says 3 to 5 years regardless of what
> you do.

Stefan,

You shouldn't see whiskers on the solder.  Three percent lead in the solder is sufficient to prevent whiskers. One of the problems with whiskers is that you can have two samples from the same batch, where one will develop whiskers, while the other does not. The parts don't have to be old to have whiskers.  Parts with newer finishes don't include tin, so they are immune.

 

That's not been my experience.
I haven't seen any whiskers on solder, but since I look I often see
them on plated metal parts (relay housings, shielding boxes, brackets,
switches, etc.) and also some components leads of ICs and such.
This has always been in very old equipment 30 years+, well pre-ROHS. I
have never found whiskers in modern or leadfree soldered equipment
myself, but don't doubt others might have.
Perhaps it is just that the old whiskers are much longer, and can be
spotted with the naked eye, but I have always considered this a legacy
problem from before they knew to avoid bright tin plating. I think in
many situations they would just burn away, they are very thin.

>From what I understand it's mostly the bright (pure) tin plating
that's the problem, and most alloy solders are fine, even if it is
just small amounts mixed in. It's also a factor how thick the plating
is (galvanic or hot dipped) but don't recall which is worse.

ST

On Sun, Jul 31, 2016 at 12:35 AM, Harvey White madyn@...
> From what I know, regular tin plating is not a problem. Mostly tin
> solder is. How long this whisker growth takes I do not know, a rough
> suspicion (and that's all it is) says 3 to 5 years regardless of what
> you do.

On Sun, 7/31/16, alan00463@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

Subject: Re: [Homebrew_PCBs] Preventing oxidation of copper outdoors
To: Homebrew_PCBs@yahoogroups.com
Date: Sunday, July 31, 2016, 3:47 AM


 









I use leaded solder too, Harvey. W.    Which is
why I wash my hands after soldering before eating.









#yiv9500515032 #yiv9500515032 --
#yiv9500515032ygrp-mkp {
border:1px solid #d8d8d8;font-family:Arial;margin:10px
0;padding:0 10px;}

#yiv9500515032 #yiv9500515032ygrp-mkp hr {
border:1px solid #d8d8d8;}

#yiv9500515032 #yiv9500515032ygrp-mkp #yiv9500515032hd {
color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px
0;}

#yiv9500515032 #yiv9500515032ygrp-mkp #yiv9500515032ads {
margin-bottom:10px;}

#yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad {
padding:0 0;}

#yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad p {
margin:0;}

#yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad a {
color:#0000ff;text-decoration:none;}
#yiv9500515032 #yiv9500515032ygrp-sponsor
#yiv9500515032ygrp-lc {
font-family:Arial;}

#yiv9500515032 #yiv9500515032ygrp-sponsor
#yiv9500515032ygrp-lc #yiv9500515032hd {
margin:10px
0px;font-weight:700;font-size:78%;line-height:122%;}

#yiv9500515032 #yiv9500515032ygrp-sponsor
#yiv9500515032ygrp-lc .yiv9500515032ad {
margin-bottom:10px;padding:0 0;}

#yiv9500515032 #yiv9500515032actions {
font-family:Verdana;font-size:11px;padding:10px 0;}

#yiv9500515032 #yiv9500515032activity {
background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}

#yiv9500515032 #yiv9500515032activity span {
font-weight:700;}

#yiv9500515032 #yiv9500515032activity span:first-child {
text-transform:uppercase;}

#yiv9500515032 #yiv9500515032activity span a {
color:#5085b6;text-decoration:none;}

#yiv9500515032 #yiv9500515032activity span span {
color:#ff7900;}

#yiv9500515032 #yiv9500515032activity span
.yiv9500515032underline {
text-decoration:underline;}

#yiv9500515032 .yiv9500515032attach {
clear:both;display:table;font-family:Arial;font-size:12px;padding:10px
0;width:400px;}

#yiv9500515032 .yiv9500515032attach div a {
text-decoration:none;}

#yiv9500515032 .yiv9500515032attach img {
border:none;padding-right:5px;}

#yiv9500515032 .yiv9500515032attach label {
display:block;margin-bottom:5px;}

#yiv9500515032 .yiv9500515032attach label a {
text-decoration:none;}

#yiv9500515032 blockquote {
margin:0 0 0 4px;}

#yiv9500515032 .yiv9500515032bold {
font-family:Arial;font-size:13px;font-weight:700;}

#yiv9500515032 .yiv9500515032bold a {
text-decoration:none;}

#yiv9500515032 dd.yiv9500515032last p a {
font-family:Verdana;font-weight:700;}

#yiv9500515032 dd.yiv9500515032last p span {
margin-right:10px;font-family:Verdana;font-weight:700;}

#yiv9500515032 dd.yiv9500515032last p
span.yiv9500515032yshortcuts {
margin-right:0;}

#yiv9500515032 div.yiv9500515032attach-table div div a {
text-decoration:none;}

#yiv9500515032 div.yiv9500515032attach-table {
width:400px;}

#yiv9500515032 div.yiv9500515032file-title a, #yiv9500515032
div.yiv9500515032file-title a:active, #yiv9500515032
div.yiv9500515032file-title a:hover, #yiv9500515032
div.yiv9500515032file-title a:visited {
text-decoration:none;}

#yiv9500515032 div.yiv9500515032photo-title a,
#yiv9500515032 div.yiv9500515032photo-title a:active,
#yiv9500515032 div.yiv9500515032photo-title a:hover,
#yiv9500515032 div.yiv9500515032photo-title a:visited {
text-decoration:none;}

#yiv9500515032 div#yiv9500515032ygrp-mlmsg
#yiv9500515032ygrp-msg p a span.yiv9500515032yshortcuts {
font-family:Verdana;font-size:10px;font-weight:normal;}

#yiv9500515032 .yiv9500515032green {
color:#628c2a;}

#yiv9500515032 .yiv9500515032MsoNormal {
margin:0 0 0 0;}

#yiv9500515032 o {
font-size:0;}

#yiv9500515032 #yiv9500515032photos div {
float:left;width:72px;}

#yiv9500515032 #yiv9500515032photos div div {
border:1px solid
#666666;min-height:62px;overflow:hidden;width:62px;}

#yiv9500515032 #yiv9500515032photos div label {
color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}

#yiv9500515032 #yiv9500515032reco-category {
font-size:77%;}

#yiv9500515032 #yiv9500515032reco-desc {
font-size:77%;}

#yiv9500515032 .yiv9500515032replbq {
margin:4px;}

#yiv9500515032 #yiv9500515032ygrp-actbar div a:first-child {
margin-right:2px;padding-right:5px;}

#yiv9500515032 #yiv9500515032ygrp-mlmsg {
font-size:13px;font-family:Arial, helvetica, clean,
sans-serif;}

#yiv9500515032 #yiv9500515032ygrp-mlmsg table {
font-size:inherit;font:100%;}

#yiv9500515032 #yiv9500515032ygrp-mlmsg select,
#yiv9500515032 input, #yiv9500515032 textarea {
font:99% Arial, Helvetica, clean, sans-serif;}

#yiv9500515032 #yiv9500515032ygrp-mlmsg pre, #yiv9500515032
code {
font:115% monospace;}

#yiv9500515032 #yiv9500515032ygrp-mlmsg * {
line-height:1.22em;}

#yiv9500515032 #yiv9500515032ygrp-mlmsg #yiv9500515032logo {
padding-bottom:10px;}


#yiv9500515032 #yiv9500515032ygrp-msg p a {
font-family:Verdana;}

#yiv9500515032 #yiv9500515032ygrp-msg
p#yiv9500515032attach-count span {
color:#1E66AE;font-weight:700;}

#yiv9500515032 #yiv9500515032ygrp-reco
#yiv9500515032reco-head {
color:#ff7900;font-weight:700;}

#yiv9500515032 #yiv9500515032ygrp-reco {
margin-bottom:20px;padding:0px;}

#yiv9500515032 #yiv9500515032ygrp-sponsor #yiv9500515032ov
li a {
font-size:130%;text-decoration:none;}

#yiv9500515032 #yiv9500515032ygrp-sponsor #yiv9500515032ov
li {
font-size:77%;list-style-type:square;padding:6px 0;}

#yiv9500515032 #yiv9500515032ygrp-sponsor #yiv9500515032ov
ul {
margin:0;padding:0 0 0 8px;}

#yiv9500515032 #yiv9500515032ygrp-text {
font-family:Georgia;}

#yiv9500515032 #yiv9500515032ygrp-text p {
margin:0 0 1em 0;}

#yiv9500515032 #yiv9500515032ygrp-text tt {
font-size:120%;}

#yiv9500515032 #yiv9500515032ygrp-vital ul li:last-child {
border-right:none !important;
}
#yiv9500515032

>Alan
>
>I use a knife and fork to eat my food, not my hands..... ;~)

>
>Malcolm
>
>I don't suffer from insanity I enjoy it!
>Mene, mene, tekel, upharsin
>The writing is on the wall.
>Ha-ktovet al ha-kir
>
>--------------------------------------------
>On Sun, 7/31/16, alan00463@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
>
> Subject: Re: [Homebrew_PCBs] Preventing oxidation of copper outdoors
> To: Homebrew_PCBs@yahoogroups.com
> Date: Sunday, July 31, 2016, 3:47 AM
>
>
>  
>
>
>
>
>
>
>
>
>
> I use leaded solder too, Harvey. W.    Which is
> why I wash my hands after soldering before eating.
>
>
>
>
>
>
>
>
>
> #yiv9500515032 #yiv9500515032 --
> #yiv9500515032ygrp-mkp {
> border:1px solid #d8d8d8;font-family:Arial;margin:10px
> 0;padding:0 10px;}
>
> #yiv9500515032 #yiv9500515032ygrp-mkp hr {
> border:1px solid #d8d8d8;}
>
> #yiv9500515032 #yiv9500515032ygrp-mkp #yiv9500515032hd {
> color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px
> 0;}
>
> #yiv9500515032 #yiv9500515032ygrp-mkp #yiv9500515032ads {
> margin-bottom:10px;}
>
> #yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad {
> padding:0 0;}
>
> #yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad p {
> margin:0;}
>
> #yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad a {
> color:#0000ff;text-decoration:none;}
> #yiv9500515032 #yiv9500515032ygrp-sponsor
> #yiv9500515032ygrp-lc {
> font-family:Arial;}
>
> #yiv9500515032 #yiv9500515032ygrp-sponsor
> #yiv9500515032ygrp-lc #yiv9500515032hd {
> margin:10px
> 0px;font-weight:700;font-size:78%;line-height:122%;}
>
> #yiv9500515032 #yiv9500515032ygrp-sponsor
> #yiv9500515032ygrp-lc .yiv9500515032ad {
> margin-bottom:10px;padding:0 0;}
>
> #yiv9500515032 #yiv9500515032actions {
> font-family:Verdana;font-size:11px;padding:10px 0;}
>
> #yiv9500515032 #yiv9500515032activity {
> background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}
>
> #yiv9500515032 #yiv9500515032activity span {
> font-weight:700;}
>
> #yiv9500515032 #yiv9500515032activity span:first-child {
> text-transform:uppercase;}
>
> #yiv9500515032 #yiv9500515032activity span a {
> color:#5085b6;text-decoration:none;}
>
> #yiv9500515032 #yiv9500515032activity span span {
> color:#ff7900;}
>
> #yiv9500515032 #yiv9500515032activity span
> .yiv9500515032underline {
> text-decoration:underline;}
>
> #yiv9500515032 .yiv9500515032attach {
> clear:both;display:table;font-family:Arial;font-size:12px;padding:10px
> 0;width:400px;}
>
> #yiv9500515032 .yiv9500515032attach div a {
> text-decoration:none;}
>
> #yiv9500515032 .yiv9500515032attach img {
> border:none;padding-right:5px;}
>
> #yiv9500515032 .yiv9500515032attach label {
> display:block;margin-bottom:5px;}
>
> #yiv9500515032 .yiv9500515032attach label a {
> text-decoration:none;}
>
> #yiv9500515032 blockquote {
> margin:0 0 0 4px;}
>
> #yiv9500515032 .yiv9500515032bold {
> font-family:Arial;font-size:13px;font-weight:700;}
>
> #yiv9500515032 .yiv9500515032bold a {
> text-decoration:none;}
>
> #yiv9500515032 dd.yiv9500515032last p a {
> font-family:Verdana;font-weight:700;}
>
> #yiv9500515032 dd.yiv9500515032last p span {
> margin-right:10px;font-family:Verdana;font-weight:700;}
>
> #yiv9500515032 dd.yiv9500515032last p
> span.yiv9500515032yshortcuts {
> margin-right:0;}
>
> #yiv9500515032 div.yiv9500515032attach-table div div a {
> text-decoration:none;}
>
> #yiv9500515032 div.yiv9500515032attach-table {
> width:400px;}
>
> #yiv9500515032 div.yiv9500515032file-title a, #yiv9500515032
> div.yiv9500515032file-title a:active, #yiv9500515032
> div.yiv9500515032file-title a:hover, #yiv9500515032
> div.yiv9500515032file-title a:visited {
> text-decoration:none;}
>
> #yiv9500515032 div.yiv9500515032photo-title a,
> #yiv9500515032 div.yiv9500515032photo-title a:active,
> #yiv9500515032 div.yiv9500515032photo-title a:hover,
> #yiv9500515032 div.yiv9500515032photo-title a:visited {
> text-decoration:none;}
>
> #yiv9500515032 div#yiv9500515032ygrp-mlmsg
> #yiv9500515032ygrp-msg p a span.yiv9500515032yshortcuts {
> font-family:Verdana;font-size:10px;font-weight:normal;}
>
> #yiv9500515032 .yiv9500515032green {
> color:#628c2a;}
>
> #yiv9500515032 .yiv9500515032MsoNormal {
> margin:0 0 0 0;}
>
> #yiv9500515032 o {
> font-size:0;}
>
> #yiv9500515032 #yiv9500515032photos div {
> float:left;width:72px;}
>
> #yiv9500515032 #yiv9500515032photos div div {
> border:1px solid
> #666666;min-height:62px;overflow:hidden;width:62px;}
>
> #yiv9500515032 #yiv9500515032photos div label {
> color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}
>
> #yiv9500515032 #yiv9500515032reco-category {
> font-size:77%;}
>
> #yiv9500515032 #yiv9500515032reco-desc {
> font-size:77%;}
>
> #yiv9500515032 .yiv9500515032replbq {
> margin:4px;}
>
> #yiv9500515032 #yiv9500515032ygrp-actbar div a:first-child {
> margin-right:2px;padding-right:5px;}
>
> #yiv9500515032 #yiv9500515032ygrp-mlmsg {
> font-size:13px;font-family:Arial, helvetica, clean,
> sans-serif;}
>
> #yiv9500515032 #yiv9500515032ygrp-mlmsg table {
> font-size:inherit;font:100%;}
>
> #yiv9500515032 #yiv9500515032ygrp-mlmsg select,
> #yiv9500515032 input, #yiv9500515032 textarea {
> font:99% Arial, Helvetica, clean, sans-serif;}
>
> #yiv9500515032 #yiv9500515032ygrp-mlmsg pre, #yiv9500515032
> code {
> font:115% monospace;}
>
> #yiv9500515032 #yiv9500515032ygrp-mlmsg * {
> line-height:1.22em;}
>
> #yiv9500515032 #yiv9500515032ygrp-mlmsg #yiv9500515032logo {
> padding-bottom:10px;}
>
>
> #yiv9500515032 #yiv9500515032ygrp-msg p a {
> font-family:Verdana;}
>
> #yiv9500515032 #yiv9500515032ygrp-msg
> p#yiv9500515032attach-count span {
> color:#1E66AE;font-weight:700;}
>
> #yiv9500515032 #yiv9500515032ygrp-reco
> #yiv9500515032reco-head {
> color:#ff7900;font-weight:700;}
>
> #yiv9500515032 #yiv9500515032ygrp-reco {
> margin-bottom:20px;padding:0px;}
>
> #yiv9500515032 #yiv9500515032ygrp-sponsor #yiv9500515032ov
> li a {
> font-size:130%;text-decoration:none;}
>
> #yiv9500515032 #yiv9500515032ygrp-sponsor #yiv9500515032ov
> li {
> font-size:77%;list-style-type:square;padding:6px 0;}
>
> #yiv9500515032 #yiv9500515032ygrp-sponsor #yiv9500515032ov
> ul {
> margin:0;padding:0 0 0 8px;}
>
> #yiv9500515032 #yiv9500515032ygrp-text {
> font-family:Georgia;}
>
> #yiv9500515032 #yiv9500515032ygrp-text p {
> margin:0 0 1em 0;}
>
> #yiv9500515032 #yiv9500515032ygrp-text tt {
> font-size:120%;}
>
> #yiv9500515032 #yiv9500515032ygrp-vital ul li:last-child {
> border-right:none !important;
> }
> #yiv9500515032

> Alan
>
> I use a knife and fork to eat my food, not my hands..... ;~)
>
> Malcolm
>
> I don't suffer from insanity I enjoy it!
> Mene, mene, tekel, upharsin
> The writing is on the wall.
> Ha-ktovet al ha-kir
>

On Sun, 7/31/16, Stefan Trethan stefan_trethan@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

Subject: Re: [Homebrew_PCBs] Preventing oxidation of copper outdoors
To: Homebrew_PCBs@yahoogroups.com
Date: Sunday, July 31, 2016, 4:23 PM


 









Do you also prepare your food without touching?
;-)



I don't worry much about the solid wire (although I do
wash my hands

of course), but the solder paste, and especially the dust
that

collects in your desoldering iron, or in the wire wool
sponge where

you wipe the tip, that's more of a hazard. So don't
just dump that in

your trash bin.



ST



On Sun, Jul 31, 2016 at 4:27 PM, Malcolm Parker-Lisberg

mparkerlisberg@... [Homebrew_PCBs]

<Homebrew_PCBs@yahoogroups.com> wrote:

> Alan

>

> I use a knife and fork to eat my food, not my
hands..... ;~)

>

> Malcolm

>

> I don't suffer from insanity I enjoy it!

> Mene, mene, tekel, upharsin

> The writing is on the wall.

> Ha-ktovet al ha-kir

>











#yiv2157096906 #yiv2157096906 --
#yiv2157096906ygrp-mkp {
border:1px solid #d8d8d8;font-family:Arial;margin:10px
0;padding:0 10px;}

#yiv2157096906 #yiv2157096906ygrp-mkp hr {
border:1px solid #d8d8d8;}

#yiv2157096906 #yiv2157096906ygrp-mkp #yiv2157096906hd {
color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px
0;}

#yiv2157096906 #yiv2157096906ygrp-mkp #yiv2157096906ads {
margin-bottom:10px;}

#yiv2157096906 #yiv2157096906ygrp-mkp .yiv2157096906ad {
padding:0 0;}

#yiv2157096906 #yiv2157096906ygrp-mkp .yiv2157096906ad p {
margin:0;}

#yiv2157096906 #yiv2157096906ygrp-mkp .yiv2157096906ad a {
color:#0000ff;text-decoration:none;}
#yiv2157096906 #yiv2157096906ygrp-sponsor
#yiv2157096906ygrp-lc {
font-family:Arial;}

#yiv2157096906 #yiv2157096906ygrp-sponsor
#yiv2157096906ygrp-lc #yiv2157096906hd {
margin:10px
0px;font-weight:700;font-size:78%;line-height:122%;}

#yiv2157096906 #yiv2157096906ygrp-sponsor
#yiv2157096906ygrp-lc .yiv2157096906ad {
margin-bottom:10px;padding:0 0;}

#yiv2157096906 #yiv2157096906actions {
font-family:Verdana;font-size:11px;padding:10px 0;}

#yiv2157096906 #yiv2157096906activity {
background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}

#yiv2157096906 #yiv2157096906activity span {
font-weight:700;}

#yiv2157096906 #yiv2157096906activity span:first-child {
text-transform:uppercase;}

#yiv2157096906 #yiv2157096906activity span a {
color:#5085b6;text-decoration:none;}

#yiv2157096906 #yiv2157096906activity span span {
color:#ff7900;}

#yiv2157096906 #yiv2157096906activity span
.yiv2157096906underline {
text-decoration:underline;}

#yiv2157096906 .yiv2157096906attach {
clear:both;display:table;font-family:Arial;font-size:12px;padding:10px
0;width:400px;}

#yiv2157096906 .yiv2157096906attach div a {
text-decoration:none;}

#yiv2157096906 .yiv2157096906attach img {
border:none;padding-right:5px;}

#yiv2157096906 .yiv2157096906attach label {
display:block;margin-bottom:5px;}

#yiv2157096906 .yiv2157096906attach label a {
text-decoration:none;}

#yiv2157096906 blockquote {
margin:0 0 0 4px;}

#yiv2157096906 .yiv2157096906bold {
font-family:Arial;font-size:13px;font-weight:700;}

#yiv2157096906 .yiv2157096906bold a {
text-decoration:none;}

#yiv2157096906 dd.yiv2157096906last p a {
font-family:Verdana;font-weight:700;}

#yiv2157096906 dd.yiv2157096906last p span {
margin-right:10px;font-family:Verdana;font-weight:700;}

#yiv2157096906 dd.yiv2157096906last p
span.yiv2157096906yshortcuts {
margin-right:0;}

#yiv2157096906 div.yiv2157096906attach-table div div a {
text-decoration:none;}

#yiv2157096906 div.yiv2157096906attach-table {
width:400px;}

#yiv2157096906 div.yiv2157096906file-title a, #yiv2157096906
div.yiv2157096906file-title a:active, #yiv2157096906
div.yiv2157096906file-title a:hover, #yiv2157096906
div.yiv2157096906file-title a:visited {
text-decoration:none;}

#yiv2157096906 div.yiv2157096906photo-title a,
#yiv2157096906 div.yiv2157096906photo-title a:active,
#yiv2157096906 div.yiv2157096906photo-title a:hover,
#yiv2157096906 div.yiv2157096906photo-title a:visited {
text-decoration:none;}

#yiv2157096906 div#yiv2157096906ygrp-mlmsg
#yiv2157096906ygrp-msg p a span.yiv2157096906yshortcuts {
font-family:Verdana;font-size:10px;font-weight:normal;}

#yiv2157096906 .yiv2157096906green {
color:#628c2a;}

#yiv2157096906 .yiv2157096906MsoNormal {
margin:0 0 0 0;}

#yiv2157096906 o {
font-size:0;}

#yiv2157096906 #yiv2157096906photos div {
float:left;width:72px;}

#yiv2157096906 #yiv2157096906photos div div {
border:1px solid
#666666;min-height:62px;overflow:hidden;width:62px;}

#yiv2157096906 #yiv2157096906photos div label {
color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}

#yiv2157096906 #yiv2157096906reco-category {
font-size:77%;}

#yiv2157096906 #yiv2157096906reco-desc {
font-size:77%;}

#yiv2157096906 .yiv2157096906replbq {
margin:4px;}

#yiv2157096906 #yiv2157096906ygrp-actbar div a:first-child {
margin-right:2px;padding-right:5px;}

#yiv2157096906 #yiv2157096906ygrp-mlmsg {
font-size:13px;font-family:Arial, helvetica, clean,
sans-serif;}

#yiv2157096906 #yiv2157096906ygrp-mlmsg table {
font-size:inherit;font:100%;}

#yiv2157096906 #yiv2157096906ygrp-mlmsg select,
#yiv2157096906 input, #yiv2157096906 textarea {
font:99% Arial, Helvetica, clean, sans-serif;}

#yiv2157096906 #yiv2157096906ygrp-mlmsg pre, #yiv2157096906
code {
font:115% monospace;}

#yiv2157096906 #yiv2157096906ygrp-mlmsg * {
line-height:1.22em;}

#yiv2157096906 #yiv2157096906ygrp-mlmsg #yiv2157096906logo {
padding-bottom:10px;}


#yiv2157096906 #yiv2157096906ygrp-msg p a {
font-family:Verdana;}

#yiv2157096906 #yiv2157096906ygrp-msg
p#yiv2157096906attach-count span {
color:#1E66AE;font-weight:700;}

#yiv2157096906 #yiv2157096906ygrp-reco
#yiv2157096906reco-head {
color:#ff7900;font-weight:700;}

#yiv2157096906 #yiv2157096906ygrp-reco {
margin-bottom:20px;padding:0px;}

#yiv2157096906 #yiv2157096906ygrp-sponsor #yiv2157096906ov
li a {
font-size:130%;text-decoration:none;}

#yiv2157096906 #yiv2157096906ygrp-sponsor #yiv2157096906ov
li {
font-size:77%;list-style-type:square;padding:6px 0;}

#yiv2157096906 #yiv2157096906ygrp-sponsor #yiv2157096906ov
ul {
margin:0;padding:0 0 0 8px;}

#yiv2157096906 #yiv2157096906ygrp-text {
font-family:Georgia;}

#yiv2157096906 #yiv2157096906ygrp-text p {
margin:0 0 1em 0;}

#yiv2157096906 #yiv2157096906ygrp-text tt {
font-size:120%;}

#yiv2157096906 #yiv2157096906ygrp-vital ul li:last-child {
border-right:none !important;
}
#yiv2157096906

 

Alan

I use a knife and fork to eat my food, not my hands..... ;~)

Malcolm

I don't suffer from insanity I enjoy it!
Mene, mene, tekel, upharsin
The writing is on the wall.
Ha-ktovet al ha-kir

--------------------------------------------

On Sun, 7/31/16, alan00463@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

Subject: Re: [Homebrew_PCBs] Preventing oxidation of copper outdoors
To: Homebrew_PCBs@yahoogroups.com
Date: Sunday, July 31, 2016, 3:47 AM


I use leaded solder too, Harvey. W.    Which is
why I wash my hands after soldering before eating.

> Stefan
>
> " Do you also prepare your food without touching? ;-) "
>
> I don't prepare the food, the wife does that.... :~)
>
> I do think there is a lot of fuss and over emphasis of what is an insignificant problem. Keep lead away from developing youngster certainly. But most of the lead on the planet that can cause polution came from and is still in cars..... Lead acid batteries.
>
> Malcolm
>

On Sun, 7/31/16, Stefan Trethan stefan_trethan@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

Subject: Re: [Homebrew_PCBs] Preventing oxidation of copper outdoors
To: Homebrew_PCBs@yahoogroups.com
Date: Sunday, July 31, 2016, 4:53 PM


 









Maybe we should ask if you touch your wife then?
;-)



I think car batteries are actually the most recycled
consumer item,

more than 99% are recycled. I agree most of the harmful lead
came from

leaded petrol in cars, lead pipes, and paint. Solder seams
in cans

poisoned a few people, but electronics solder was never a
health

hazard for us.



However when I do see where our electronic junk ends up now,
in Asia

and Africa, and how it is treated there, I suffer the
leadfree solder

gladly, and quietly.

Until we get our act together and treat our waste properly
the least

we can do is make it as non-toxic as possible.



Did you know there is statistical evidence that the phasing
out of

leaded petrol and paint caused a subsequent drop in crime in
the

following decades?



ST



On Sun, Jul 31, 2016 at 5:37 PM, Malcolm Parker-Lisberg

mparkerlisberg@... [Homebrew_PCBs]

<Homebrew_PCBs@yahoogroups.com> wrote:

> Stefan

>

> " Do you also prepare your food without
touching? ;-) "

>

> I don't prepare the food, the wife does that....
:~)

>

> I do think there is a lot of fuss and over emphasis of
what is an insignificant problem. Keep lead away from
developing youngster certainly. But most of the lead on the
planet that can cause polution came from and is still in
cars..... Lead acid batteries.

>

> Malcolm

>











#yiv3528499868 #yiv3528499868 --
#yiv3528499868ygrp-mkp {
border:1px solid #d8d8d8;font-family:Arial;margin:10px
0;padding:0 10px;}

#yiv3528499868 #yiv3528499868ygrp-mkp hr {
border:1px solid #d8d8d8;}

#yiv3528499868 #yiv3528499868ygrp-mkp #yiv3528499868hd {
color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px
0;}

#yiv3528499868 #yiv3528499868ygrp-mkp #yiv3528499868ads {
margin-bottom:10px;}

#yiv3528499868 #yiv3528499868ygrp-mkp .yiv3528499868ad {
padding:0 0;}

#yiv3528499868 #yiv3528499868ygrp-mkp .yiv3528499868ad p {
margin:0;}

#yiv3528499868 #yiv3528499868ygrp-mkp .yiv3528499868ad a {
color:#0000ff;text-decoration:none;}
#yiv3528499868 #yiv3528499868ygrp-sponsor
#yiv3528499868ygrp-lc {
font-family:Arial;}

#yiv3528499868 #yiv3528499868ygrp-sponsor
#yiv3528499868ygrp-lc #yiv3528499868hd {
margin:10px
0px;font-weight:700;font-size:78%;line-height:122%;}

#yiv3528499868 #yiv3528499868ygrp-sponsor
#yiv3528499868ygrp-lc .yiv3528499868ad {
margin-bottom:10px;padding:0 0;}

#yiv3528499868 #yiv3528499868actions {
font-family:Verdana;font-size:11px;padding:10px 0;}

#yiv3528499868 #yiv3528499868activity {
background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}

#yiv3528499868 #yiv3528499868activity span {
font-weight:700;}

#yiv3528499868 #yiv3528499868activity span:first-child {
text-transform:uppercase;}

#yiv3528499868 #yiv3528499868activity span a {
color:#5085b6;text-decoration:none;}

#yiv3528499868 #yiv3528499868activity span span {
color:#ff7900;}

#yiv3528499868 #yiv3528499868activity span
.yiv3528499868underline {
text-decoration:underline;}

#yiv3528499868 .yiv3528499868attach {
clear:both;display:table;font-family:Arial;font-size:12px;padding:10px
0;width:400px;}

#yiv3528499868 .yiv3528499868attach div a {
text-decoration:none;}

#yiv3528499868 .yiv3528499868attach img {
border:none;padding-right:5px;}

#yiv3528499868 .yiv3528499868attach label {
display:block;margin-bottom:5px;}

#yiv3528499868 .yiv3528499868attach label a {
text-decoration:none;}

#yiv3528499868 blockquote {
margin:0 0 0 4px;}

#yiv3528499868 .yiv3528499868bold {
font-family:Arial;font-size:13px;font-weight:700;}

#yiv3528499868 .yiv3528499868bold a {
text-decoration:none;}

#yiv3528499868 dd.yiv3528499868last p a {
font-family:Verdana;font-weight:700;}

#yiv3528499868 dd.yiv3528499868last p span {
margin-right:10px;font-family:Verdana;font-weight:700;}

#yiv3528499868 dd.yiv3528499868last p
span.yiv3528499868yshortcuts {
margin-right:0;}

#yiv3528499868 div.yiv3528499868attach-table div div a {
text-decoration:none;}

#yiv3528499868 div.yiv3528499868attach-table {
width:400px;}

#yiv3528499868 div.yiv3528499868file-title a, #yiv3528499868
div.yiv3528499868file-title a:active, #yiv3528499868
div.yiv3528499868file-title a:hover, #yiv3528499868
div.yiv3528499868file-title a:visited {
text-decoration:none;}

#yiv3528499868 div.yiv3528499868photo-title a,
#yiv3528499868 div.yiv3528499868photo-title a:active,
#yiv3528499868 div.yiv3528499868photo-title a:hover,
#yiv3528499868 div.yiv3528499868photo-title a:visited {
text-decoration:none;}

#yiv3528499868 div#yiv3528499868ygrp-mlmsg
#yiv3528499868ygrp-msg p a span.yiv3528499868yshortcuts {
font-family:Verdana;font-size:10px;font-weight:normal;}

#yiv3528499868 .yiv3528499868green {
color:#628c2a;}

#yiv3528499868 .yiv3528499868MsoNormal {
margin:0 0 0 0;}

#yiv3528499868 o {
font-size:0;}

#yiv3528499868 #yiv3528499868photos div {
float:left;width:72px;}

#yiv3528499868 #yiv3528499868photos div div {
border:1px solid
#666666;min-height:62px;overflow:hidden;width:62px;}

#yiv3528499868 #yiv3528499868photos div label {
color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}

#yiv3528499868 #yiv3528499868reco-category {
font-size:77%;}

#yiv3528499868 #yiv3528499868reco-desc {
font-size:77%;}

#yiv3528499868 .yiv3528499868replbq {
margin:4px;}

#yiv3528499868 #yiv3528499868ygrp-actbar div a:first-child {
margin-right:2px;padding-right:5px;}

#yiv3528499868 #yiv3528499868ygrp-mlmsg {
font-size:13px;font-family:Arial, helvetica, clean,
sans-serif;}

#yiv3528499868 #yiv3528499868ygrp-mlmsg table {
font-size:inherit;font:100%;}

#yiv3528499868 #yiv3528499868ygrp-mlmsg select,
#yiv3528499868 input, #yiv3528499868 textarea {
font:99% Arial, Helvetica, clean, sans-serif;}

#yiv3528499868 #yiv3528499868ygrp-mlmsg pre, #yiv3528499868
code {
font:115% monospace;}

#yiv3528499868 #yiv3528499868ygrp-mlmsg * {
line-height:1.22em;}

#yiv3528499868 #yiv3528499868ygrp-mlmsg #yiv3528499868logo {
padding-bottom:10px;}


#yiv3528499868 #yiv3528499868ygrp-msg p a {
font-family:Verdana;}

#yiv3528499868 #yiv3528499868ygrp-msg
p#yiv3528499868attach-count span {
color:#1E66AE;font-weight:700;}

#yiv3528499868 #yiv3528499868ygrp-reco
#yiv3528499868reco-head {
color:#ff7900;font-weight:700;}

#yiv3528499868 #yiv3528499868ygrp-reco {
margin-bottom:20px;padding:0px;}

#yiv3528499868 #yiv3528499868ygrp-sponsor #yiv3528499868ov
li a {
font-size:130%;text-decoration:none;}

#yiv3528499868 #yiv3528499868ygrp-sponsor #yiv3528499868ov
li {
font-size:77%;list-style-type:square;padding:6px 0;}

#yiv3528499868 #yiv3528499868ygrp-sponsor #yiv3528499868ov
ul {
margin:0;padding:0 0 0 8px;}

#yiv3528499868 #yiv3528499868ygrp-text {
font-family:Georgia;}

#yiv3528499868 #yiv3528499868ygrp-text p {
margin:0 0 1em 0;}

#yiv3528499868 #yiv3528499868ygrp-text tt {
font-size:120%;}

#yiv3528499868 #yiv3528499868ygrp-vital ul li:last-child {
border-right:none !important;
}
#yiv3528499868

On Sun, 7/31/16, Harvey White madyn@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

Subject: Re: [Homebrew_PCBs] Preventing oxidation of copper outdoors
To: Homebrew_PCBs@yahoogroups.com
Date: Sunday, July 31, 2016, 4:10 PM


 









On Sun, 31 Jul 2016 14:27:19 +0000 (UTC), you
wrote:



>Alan

>

>I use a knife and fork to eat my food, not my hands.....
;~)



What, including sandwiches?



Harvey



>

>Malcolm

>

>I don't suffer from insanity I enjoy it!

>Mene, mene, tekel, upharsin

>The writing is on the wall.

>Ha-ktovet al ha-kir

>

>--------------------------------------------

>On Sun, 7/31/16, alan00463@... [Homebrew_PCBs]
<Homebrew_PCBs@yahoogroups.com> wrote:

>

> Subject: Re: [Homebrew_PCBs] Preventing oxidation of
copper outdoors

> To: Homebrew_PCBs@yahoogroups.com

> Date: Sunday, July 31, 2016, 3:47 AM

>

>

>  

>

>

>

>

>

>

>

>

>

> I use leaded solder too, Harvey. W.    Which
is

> why I wash my hands after soldering before eating.

>

>

>

>

>

>

>

>

>

> #yiv9500515032 #yiv9500515032 --

> #yiv9500515032ygrp-mkp {

> border:1px solid
#d8d8d8;font-family:Arial;margin:10px

> 0;padding:0 10px;}

>

> #yiv9500515032 #yiv9500515032ygrp-mkp hr {

> border:1px solid #d8d8d8;}

>

> #yiv9500515032 #yiv9500515032ygrp-mkp #yiv9500515032hd
{

>
color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px

> 0;}

>

> #yiv9500515032 #yiv9500515032ygrp-mkp #yiv9500515032ads
{

> margin-bottom:10px;}

>

> #yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad
{

> padding:0 0;}

>

> #yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad
p {

> margin:0;}

>

> #yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad
a {

> color:#0000ff;text-decoration:none;}

> #yiv9500515032 #yiv9500515032ygrp-sponsor

> #yiv9500515032ygrp-lc {

> font-family:Arial;}

>

> #yiv9500515032 #yiv9500515032ygrp-sponsor

> #yiv9500515032ygrp-lc #yiv9500515032hd {

> margin:10px

> 0px;font-weight:700;font-size:78%;line-height:122%;}

>

> #yiv9500515032 #yiv9500515032ygrp-sponsor

> #yiv9500515032ygrp-lc .yiv9500515032ad {

> margin-bottom:10px;padding:0 0;}

>

> #yiv9500515032 #yiv9500515032actions {

> font-family:Verdana;font-size:11px;padding:10px 0;}

>

> #yiv9500515032 #yiv9500515032activity {

>
background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}

>

> #yiv9500515032 #yiv9500515032activity span {

> font-weight:700;}

>

> #yiv9500515032 #yiv9500515032activity span:first-child
{

> text-transform:uppercase;}

>

> #yiv9500515032 #yiv9500515032activity span a {

> color:#5085b6;text-decoration:none;}

>

> #yiv9500515032 #yiv9500515032activity span span {

> color:#ff7900;}

>

> #yiv9500515032 #yiv9500515032activity span

> .yiv9500515032underline {

> text-decoration:underline;}

>

> #yiv9500515032 .yiv9500515032attach {

>
clear:both;display:table;font-family:Arial;font-size:12px;padding:10px

> 0;width:400px;}

>

> #yiv9500515032 .yiv9500515032attach div a {

> text-decoration:none;}

>

> #yiv9500515032 .yiv9500515032attach img {

> border:none;padding-right:5px;}

>

> #yiv9500515032 .yiv9500515032attach label {

> display:block;margin-bottom:5px;}

>

> #yiv9500515032 .yiv9500515032attach label a {

> text-decoration:none;}

>

> #yiv9500515032 blockquote {

> margin:0 0 0 4px;}

>

> #yiv9500515032 .yiv9500515032bold {

> font-family:Arial;font-size:13px;font-weight:700;}

>

> #yiv9500515032 .yiv9500515032bold a {

> text-decoration:none;}

>

> #yiv9500515032 dd.yiv9500515032last p a {

> font-family:Verdana;font-weight:700;}

>

> #yiv9500515032 dd.yiv9500515032last p span {

>
margin-right:10px;font-family:Verdana;font-weight:700;}

>

> #yiv9500515032 dd.yiv9500515032last p

> span.yiv9500515032yshortcuts {

> margin-right:0;}

>

> #yiv9500515032 div.yiv9500515032attach-table div div a
{

> text-decoration:none;}

>

> #yiv9500515032 div.yiv9500515032attach-table {

> width:400px;}

>

> #yiv9500515032 div.yiv9500515032file-title a,
#yiv9500515032

> div.yiv9500515032file-title a:active, #yiv9500515032

> div.yiv9500515032file-title a:hover, #yiv9500515032

> div.yiv9500515032file-title a:visited {

> text-decoration:none;}

>

> #yiv9500515032 div.yiv9500515032photo-title a,

> #yiv9500515032 div.yiv9500515032photo-title
a:active,

> #yiv9500515032 div.yiv9500515032photo-title a:hover,

> #yiv9500515032 div.yiv9500515032photo-title a:visited
{

> text-decoration:none;}

>

> #yiv9500515032 div#yiv9500515032ygrp-mlmsg

> #yiv9500515032ygrp-msg p a span.yiv9500515032yshortcuts
{

>
font-family:Verdana;font-size:10px;font-weight:normal;}

>

> #yiv9500515032 .yiv9500515032green {

> color:#628c2a;}

>

> #yiv9500515032 .yiv9500515032MsoNormal {

> margin:0 0 0 0;}

>

> #yiv9500515032 o {

> font-size:0;}

>

> #yiv9500515032 #yiv9500515032photos div {

> float:left;width:72px;}

>

> #yiv9500515032 #yiv9500515032photos div div {

> border:1px solid

> #666666;min-height:62px;overflow:hidden;width:62px;}

>

> #yiv9500515032 #yiv9500515032photos div label {

>
color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}

>

> #yiv9500515032 #yiv9500515032reco-category {

> font-size:77%;}

>

> #yiv9500515032 #yiv9500515032reco-desc {

> font-size:77%;}

>

> #yiv9500515032 .yiv9500515032replbq {

> margin:4px;}

>

> #yiv9500515032 #yiv9500515032ygrp-actbar div
a:first-child {

> margin-right:2px;padding-right:5px;}

>

> #yiv9500515032 #yiv9500515032ygrp-mlmsg {

> font-size:13px;font-family:Arial, helvetica, clean,

> sans-serif;}

>

> #yiv9500515032 #yiv9500515032ygrp-mlmsg table {

> font-size:inherit;font:100%;}

>

> #yiv9500515032 #yiv9500515032ygrp-mlmsg select,

> #yiv9500515032 input, #yiv9500515032 textarea {

> font:99% Arial, Helvetica, clean, sans-serif;}

>

> #yiv9500515032 #yiv9500515032ygrp-mlmsg pre,
#yiv9500515032

> code {

> font:115% monospace;}

>

> #yiv9500515032 #yiv9500515032ygrp-mlmsg * {

> line-height:1.22em;}

>

> #yiv9500515032 #yiv9500515032ygrp-mlmsg
#yiv9500515032logo {

> padding-bottom:10px;}

>

>

> #yiv9500515032 #yiv9500515032ygrp-msg p a {

> font-family:Verdana;}

>

> #yiv9500515032 #yiv9500515032ygrp-msg

> p#yiv9500515032attach-count span {

> color:#1E66AE;font-weight:700;}

>

> #yiv9500515032 #yiv9500515032ygrp-reco

> #yiv9500515032reco-head {

> color:#ff7900;font-weight:700;}

>

> #yiv9500515032 #yiv9500515032ygrp-reco {

> margin-bottom:20px;padding:0px;}

>

> #yiv9500515032 #yiv9500515032ygrp-sponsor
#yiv9500515032ov

> li a {

> font-size:130%;text-decoration:none;}

>

> #yiv9500515032 #yiv9500515032ygrp-sponsor
#yiv9500515032ov

> li {

> font-size:77%;list-style-type:square;padding:6px 0;}

>

> #yiv9500515032 #yiv9500515032ygrp-sponsor
#yiv9500515032ov

> ul {

> margin:0;padding:0 0 0 8px;}

>

> #yiv9500515032 #yiv9500515032ygrp-text {

> font-family:Georgia;}

>

> #yiv9500515032 #yiv9500515032ygrp-text p {

> margin:0 0 1em 0;}

>

> #yiv9500515032 #yiv9500515032ygrp-text tt {

> font-size:120%;}

>

> #yiv9500515032 #yiv9500515032ygrp-vital ul
li:last-child {

> border-right:none !important;

> }

> #yiv9500515032













#yiv5874393226 #yiv5874393226 --
#yiv5874393226ygrp-mkp {
border:1px solid #d8d8d8;font-family:Arial;margin:10px
0;padding:0 10px;}

#yiv5874393226 #yiv5874393226ygrp-mkp hr {
border:1px solid #d8d8d8;}

#yiv5874393226 #yiv5874393226ygrp-mkp #yiv5874393226hd {
color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px
0;}

#yiv5874393226 #yiv5874393226ygrp-mkp #yiv5874393226ads {
margin-bottom:10px;}

#yiv5874393226 #yiv5874393226ygrp-mkp .yiv5874393226ad {
padding:0 0;}

#yiv5874393226 #yiv5874393226ygrp-mkp .yiv5874393226ad p {
margin:0;}

#yiv5874393226 #yiv5874393226ygrp-mkp .yiv5874393226ad a {
color:#0000ff;text-decoration:none;}
#yiv5874393226 #yiv5874393226ygrp-sponsor
#yiv5874393226ygrp-lc {
font-family:Arial;}

#yiv5874393226 #yiv5874393226ygrp-sponsor
#yiv5874393226ygrp-lc #yiv5874393226hd {
margin:10px
0px;font-weight:700;font-size:78%;line-height:122%;}

#yiv5874393226 #yiv5874393226ygrp-sponsor
#yiv5874393226ygrp-lc .yiv5874393226ad {
margin-bottom:10px;padding:0 0;}

#yiv5874393226 #yiv5874393226actions {
font-family:Verdana;font-size:11px;padding:10px 0;}

#yiv5874393226 #yiv5874393226activity {
background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}

#yiv5874393226 #yiv5874393226activity span {
font-weight:700;}

#yiv5874393226 #yiv5874393226activity span:first-child {
text-transform:uppercase;}

#yiv5874393226 #yiv5874393226activity span a {
color:#5085b6;text-decoration:none;}

#yiv5874393226 #yiv5874393226activity span span {
color:#ff7900;}

#yiv5874393226 #yiv5874393226activity span
.yiv5874393226underline {
text-decoration:underline;}

#yiv5874393226 .yiv5874393226attach {
clear:both;display:table;font-family:Arial;font-size:12px;padding:10px
0;width:400px;}

#yiv5874393226 .yiv5874393226attach div a {
text-decoration:none;}

#yiv5874393226 .yiv5874393226attach img {
border:none;padding-right:5px;}

#yiv5874393226 .yiv5874393226attach label {
display:block;margin-bottom:5px;}

#yiv5874393226 .yiv5874393226attach label a {
text-decoration:none;}

#yiv5874393226 blockquote {
margin:0 0 0 4px;}

#yiv5874393226 .yiv5874393226bold {
font-family:Arial;font-size:13px;font-weight:700;}

#yiv5874393226 .yiv5874393226bold a {
text-decoration:none;}

#yiv5874393226 dd.yiv5874393226last p a {
font-family:Verdana;font-weight:700;}

#yiv5874393226 dd.yiv5874393226last p span {
margin-right:10px;font-family:Verdana;font-weight:700;}

#yiv5874393226 dd.yiv5874393226last p
span.yiv5874393226yshortcuts {
margin-right:0;}

#yiv5874393226 div.yiv5874393226attach-table div div a {
text-decoration:none;}

#yiv5874393226 div.yiv5874393226attach-table {
width:400px;}

#yiv5874393226 div.yiv5874393226file-title a, #yiv5874393226
div.yiv5874393226file-title a:active, #yiv5874393226
div.yiv5874393226file-title a:hover, #yiv5874393226
div.yiv5874393226file-title a:visited {
text-decoration:none;}

#yiv5874393226 div.yiv5874393226photo-title a,
#yiv5874393226 div.yiv5874393226photo-title a:active,
#yiv5874393226 div.yiv5874393226photo-title a:hover,
#yiv5874393226 div.yiv5874393226photo-title a:visited {
text-decoration:none;}

#yiv5874393226 div#yiv5874393226ygrp-mlmsg
#yiv5874393226ygrp-msg p a span.yiv5874393226yshortcuts {
font-family:Verdana;font-size:10px;font-weight:normal;}

#yiv5874393226 .yiv5874393226green {
color:#628c2a;}

#yiv5874393226 .yiv5874393226MsoNormal {
margin:0 0 0 0;}

#yiv5874393226 o {
font-size:0;}

#yiv5874393226 #yiv5874393226photos div {
float:left;width:72px;}

#yiv5874393226 #yiv5874393226photos div div {
border:1px solid
#666666;min-height:62px;overflow:hidden;width:62px;}

#yiv5874393226 #yiv5874393226photos div label {
color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}

#yiv5874393226 #yiv5874393226reco-category {
font-size:77%;}

#yiv5874393226 #yiv5874393226reco-desc {
font-size:77%;}

#yiv5874393226 .yiv5874393226replbq {
margin:4px;}

#yiv5874393226 #yiv5874393226ygrp-actbar div a:first-child {
margin-right:2px;padding-right:5px;}

#yiv5874393226 #yiv5874393226ygrp-mlmsg {
font-size:13px;font-family:Arial, helvetica, clean,
sans-serif;}

#yiv5874393226 #yiv5874393226ygrp-mlmsg table {
font-size:inherit;font:100%;}

#yiv5874393226 #yiv5874393226ygrp-mlmsg select,
#yiv5874393226 input, #yiv5874393226 textarea {
font:99% Arial, Helvetica, clean, sans-serif;}

#yiv5874393226 #yiv5874393226ygrp-mlmsg pre, #yiv5874393226
code {
font:115% monospace;}

#yiv5874393226 #yiv5874393226ygrp-mlmsg * {
line-height:1.22em;}

#yiv5874393226 #yiv5874393226ygrp-mlmsg #yiv5874393226logo {
padding-bottom:10px;}


#yiv5874393226 #yiv5874393226ygrp-msg p a {
font-family:Verdana;}

#yiv5874393226 #yiv5874393226ygrp-msg
p#yiv5874393226attach-count span {
color:#1E66AE;font-weight:700;}

#yiv5874393226 #yiv5874393226ygrp-reco
#yiv5874393226reco-head {
color:#ff7900;font-weight:700;}

#yiv5874393226 #yiv5874393226ygrp-reco {
margin-bottom:20px;padding:0px;}

#yiv5874393226 #yiv5874393226ygrp-sponsor #yiv5874393226ov
li a {
font-size:130%;text-decoration:none;}

#yiv5874393226 #yiv5874393226ygrp-sponsor #yiv5874393226ov
li {
font-size:77%;list-style-type:square;padding:6px 0;}

#yiv5874393226 #yiv5874393226ygrp-sponsor #yiv5874393226ov
ul {
margin:0;padding:0 0 0 8px;}

#yiv5874393226 #yiv5874393226ygrp-text {
font-family:Georgia;}

#yiv5874393226 #yiv5874393226ygrp-text p {
margin:0 0 1em 0;}

#yiv5874393226 #yiv5874393226ygrp-text tt {
font-size:120%;}

#yiv5874393226 #yiv5874393226ygrp-vital ul li:last-child {
border-right:none !important;
}
#yiv5874393226

> Don't often, she always has a headache.......
>
> If I recall, "There are Lies, Damn Lies and Statistics"
>
> Just sort out the recycling, that is all that is needed.
> The resourses of the planet are there to be used, but wisely, not just banned..
>
> Malcolm

>Harvey
>
>For toasted sandwhiches..............
>Otherwise, hold the crust and feed that to the pesky Pigeons or Grey Squirrels.

>
>Malcolm
>
>I don't suffer from insanity I enjoy it!
>Mene, mene, tekel, upharsin
>The writing is on the wall.
>Ha-ktovet al ha-kir
>
>--------------------------------------------
>On Sun, 7/31/16, Harvey White madyn@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
>
> Subject: Re: [Homebrew_PCBs] Preventing oxidation of copper outdoors
> To: Homebrew_PCBs@yahoogroups.com
> Date: Sunday, July 31, 2016, 4:10 PM
>
>
>  
>
>
>
>
>
>
>
>
>
> On Sun, 31 Jul 2016 14:27:19 +0000 (UTC), you
> wrote:
>
>
>
> >Alan
>
> >
>
> >I use a knife and fork to eat my food, not my hands.....
> ;~)
>
>
>
> What, including sandwiches?
>
>
>
> Harvey
>
>
>
> >
>
> >Malcolm
>
> >
>
> >I don't suffer from insanity I enjoy it!
>
> >Mene, mene, tekel, upharsin
>
> >The writing is on the wall.
>
> >Ha-ktovet al ha-kir
>
> >
>
> >--------------------------------------------
>
> >On Sun, 7/31/16, alan00463@... [Homebrew_PCBs]
> <Homebrew_PCBs@yahoogroups.com> wrote:
>
> >
>
> > Subject: Re: [Homebrew_PCBs] Preventing oxidation of
> copper outdoors
>
> > To: Homebrew_PCBs@yahoogroups.com
>
> > Date: Sunday, July 31, 2016, 3:47 AM
>
> >
>
> >
>
> >  
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> > I use leaded solder too, Harvey. W.    Which
> is
>
> > why I wash my hands after soldering before eating.
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> > #yiv9500515032 #yiv9500515032 --
>
> > #yiv9500515032ygrp-mkp {
>
> > border:1px solid
> #d8d8d8;font-family:Arial;margin:10px
>
> > 0;padding:0 10px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mkp hr {
>
> > border:1px solid #d8d8d8;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mkp #yiv9500515032hd
> {
>
> >
> color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px
>
> > 0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mkp #yiv9500515032ads
> {
>
> > margin-bottom:10px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad
> {
>
> > padding:0 0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad
> p {
>
> > margin:0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad
> a {
>
> > color:#0000ff;text-decoration:none;}
>
> > #yiv9500515032 #yiv9500515032ygrp-sponsor
>
> > #yiv9500515032ygrp-lc {
>
> > font-family:Arial;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-sponsor
>
> > #yiv9500515032ygrp-lc #yiv9500515032hd {
>
> > margin:10px
>
> > 0px;font-weight:700;font-size:78%;line-height:122%;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-sponsor
>
> > #yiv9500515032ygrp-lc .yiv9500515032ad {
>
> > margin-bottom:10px;padding:0 0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032actions {
>
> > font-family:Verdana;font-size:11px;padding:10px 0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032activity {
>
> >
> background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032activity span {
>
> > font-weight:700;}
>
> >
>
> > #yiv9500515032 #yiv9500515032activity span:first-child
> {
>
> > text-transform:uppercase;}
>
> >
>
> > #yiv9500515032 #yiv9500515032activity span a {
>
> > color:#5085b6;text-decoration:none;}
>
> >
>
> > #yiv9500515032 #yiv9500515032activity span span {
>
> > color:#ff7900;}
>
> >
>
> > #yiv9500515032 #yiv9500515032activity span
>
> > .yiv9500515032underline {
>
> > text-decoration:underline;}
>
> >
>
> > #yiv9500515032 .yiv9500515032attach {
>
> >
> clear:both;display:table;font-family:Arial;font-size:12px;padding:10px
>
> > 0;width:400px;}
>
> >
>
> > #yiv9500515032 .yiv9500515032attach div a {
>
> > text-decoration:none;}
>
> >
>
> > #yiv9500515032 .yiv9500515032attach img {
>
> > border:none;padding-right:5px;}
>
> >
>
> > #yiv9500515032 .yiv9500515032attach label {
>
> > display:block;margin-bottom:5px;}
>
> >
>
> > #yiv9500515032 .yiv9500515032attach label a {
>
> > text-decoration:none;}
>
> >
>
> > #yiv9500515032 blockquote {
>
> > margin:0 0 0 4px;}
>
> >
>
> > #yiv9500515032 .yiv9500515032bold {
>
> > font-family:Arial;font-size:13px;font-weight:700;}
>
> >
>
> > #yiv9500515032 .yiv9500515032bold a {
>
> > text-decoration:none;}
>
> >
>
> > #yiv9500515032 dd.yiv9500515032last p a {
>
> > font-family:Verdana;font-weight:700;}
>
> >
>
> > #yiv9500515032 dd.yiv9500515032last p span {
>
> >
> margin-right:10px;font-family:Verdana;font-weight:700;}
>
> >
>
> > #yiv9500515032 dd.yiv9500515032last p
>
> > span.yiv9500515032yshortcuts {
>
> > margin-right:0;}
>
> >
>
> > #yiv9500515032 div.yiv9500515032attach-table div div a
> {
>
> > text-decoration:none;}
>
> >
>
> > #yiv9500515032 div.yiv9500515032attach-table {
>
> > width:400px;}
>
> >
>
> > #yiv9500515032 div.yiv9500515032file-title a,
> #yiv9500515032
>
> > div.yiv9500515032file-title a:active, #yiv9500515032
>
> > div.yiv9500515032file-title a:hover, #yiv9500515032
>
> > div.yiv9500515032file-title a:visited {
>
> > text-decoration:none;}
>
> >
>
> > #yiv9500515032 div.yiv9500515032photo-title a,
>
> > #yiv9500515032 div.yiv9500515032photo-title
> a:active,
>
> > #yiv9500515032 div.yiv9500515032photo-title a:hover,
>
> > #yiv9500515032 div.yiv9500515032photo-title a:visited
> {
>
> > text-decoration:none;}
>
> >
>
> > #yiv9500515032 div#yiv9500515032ygrp-mlmsg
>
> > #yiv9500515032ygrp-msg p a span.yiv9500515032yshortcuts
> {
>
> >
> font-family:Verdana;font-size:10px;font-weight:normal;}
>
> >
>
> > #yiv9500515032 .yiv9500515032green {
>
> > color:#628c2a;}
>
> >
>
> > #yiv9500515032 .yiv9500515032MsoNormal {
>
> > margin:0 0 0 0;}
>
> >
>
> > #yiv9500515032 o {
>
> > font-size:0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032photos div {
>
> > float:left;width:72px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032photos div div {
>
> > border:1px solid
>
> > #666666;min-height:62px;overflow:hidden;width:62px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032photos div label {
>
> >
> color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032reco-category {
>
> > font-size:77%;}
>
> >
>
> > #yiv9500515032 #yiv9500515032reco-desc {
>
> > font-size:77%;}
>
> >
>
> > #yiv9500515032 .yiv9500515032replbq {
>
> > margin:4px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-actbar div
> a:first-child {
>
> > margin-right:2px;padding-right:5px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mlmsg {
>
> > font-size:13px;font-family:Arial, helvetica, clean,
>
> > sans-serif;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mlmsg table {
>
> > font-size:inherit;font:100%;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mlmsg select,
>
> > #yiv9500515032 input, #yiv9500515032 textarea {
>
> > font:99% Arial, Helvetica, clean, sans-serif;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mlmsg pre,
> #yiv9500515032
>
> > code {
>
> > font:115% monospace;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mlmsg * {
>
> > line-height:1.22em;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mlmsg
> #yiv9500515032logo {
>
> > padding-bottom:10px;}
>
> >
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-msg p a {
>
> > font-family:Verdana;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-msg
>
> > p#yiv9500515032attach-count span {
>
> > color:#1E66AE;font-weight:700;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-reco
>
> > #yiv9500515032reco-head {
>
> > color:#ff7900;font-weight:700;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-reco {
>
> > margin-bottom:20px;padding:0px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-sponsor
> #yiv9500515032ov
>
> > li a {
>
> > font-size:130%;text-decoration:none;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-sponsor
> #yiv9500515032ov
>
> > li {
>
> > font-size:77%;list-style-type:square;padding:6px 0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-sponsor
> #yiv9500515032ov
>
> > ul {
>
> > margin:0;padding:0 0 0 8px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-text {
>
> > font-family:Georgia;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-text p {
>
> > margin:0 0 1em 0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-text tt {
>
> > font-size:120%;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-vital ul
> li:last-child {
>
> > border-right:none !important;
>
> > }
>
> > #yiv9500515032
>
>
>
>
>
>
>
>
>
>
>
>
>
> #yiv5874393226 #yiv5874393226 --
> #yiv5874393226ygrp-mkp {
> border:1px solid #d8d8d8;font-family:Arial;margin:10px
> 0;padding:0 10px;}
>
> #yiv5874393226 #yiv5874393226ygrp-mkp hr {
> border:1px solid #d8d8d8;}
>
> #yiv5874393226 #yiv5874393226ygrp-mkp #yiv5874393226hd {
> color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px
> 0;}
>
> #yiv5874393226 #yiv5874393226ygrp-mkp #yiv5874393226ads {
> margin-bottom:10px;}
>
> #yiv5874393226 #yiv5874393226ygrp-mkp .yiv5874393226ad {
> padding:0 0;}
>
> #yiv5874393226 #yiv5874393226ygrp-mkp .yiv5874393226ad p {
> margin:0;}
>
> #yiv5874393226 #yiv5874393226ygrp-mkp .yiv5874393226ad a {
> color:#0000ff;text-decoration:none;}
> #yiv5874393226 #yiv5874393226ygrp-sponsor
> #yiv5874393226ygrp-lc {
> font-family:Arial;}
>
> #yiv5874393226 #yiv5874393226ygrp-sponsor
> #yiv5874393226ygrp-lc #yiv5874393226hd {
> margin:10px
> 0px;font-weight:700;font-size:78%;line-height:122%;}
>
> #yiv5874393226 #yiv5874393226ygrp-sponsor
> #yiv5874393226ygrp-lc .yiv5874393226ad {
> margin-bottom:10px;padding:0 0;}
>
> #yiv5874393226 #yiv5874393226actions {
> font-family:Verdana;font-size:11px;padding:10px 0;}
>
> #yiv5874393226 #yiv5874393226activity {
> background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}
>
> #yiv5874393226 #yiv5874393226activity span {
> font-weight:700;}
>
> #yiv5874393226 #yiv5874393226activity span:first-child {
> text-transform:uppercase;}
>
> #yiv5874393226 #yiv5874393226activity span a {
> color:#5085b6;text-decoration:none;}
>
> #yiv5874393226 #yiv5874393226activity span span {
> color:#ff7900;}
>
> #yiv5874393226 #yiv5874393226activity span
> .yiv5874393226underline {
> text-decoration:underline;}
>
> #yiv5874393226 .yiv5874393226attach {
> clear:both;display:table;font-family:Arial;font-size:12px;padding:10px
> 0;width:400px;}
>
> #yiv5874393226 .yiv5874393226attach div a {
> text-decoration:none;}
>
> #yiv5874393226 .yiv5874393226attach img {
> border:none;padding-right:5px;}
>
> #yiv5874393226 .yiv5874393226attach label {
> display:block;margin-bottom:5px;}
>
> #yiv5874393226 .yiv5874393226attach label a {
> text-decoration:none;}
>
> #yiv5874393226 blockquote {
> margin:0 0 0 4px;}
>
> #yiv5874393226 .yiv5874393226bold {
> font-family:Arial;font-size:13px;font-weight:700;}
>
> #yiv5874393226 .yiv5874393226bold a {
> text-decoration:none;}
>
> #yiv5874393226 dd.yiv5874393226last p a {
> font-family:Verdana;font-weight:700;}
>
> #yiv5874393226 dd.yiv5874393226last p span {
> margin-right:10px;font-family:Verdana;font-weight:700;}
>
> #yiv5874393226 dd.yiv5874393226last p
> span.yiv5874393226yshortcuts {
> margin-right:0;}
>
> #yiv5874393226 div.yiv5874393226attach-table div div a {
> text-decoration:none;}
>
> #yiv5874393226 div.yiv5874393226attach-table {
> width:400px;}
>
> #yiv5874393226 div.yiv5874393226file-title a, #yiv5874393226
> div.yiv5874393226file-title a:active, #yiv5874393226
> div.yiv5874393226file-title a:hover, #yiv5874393226
> div.yiv5874393226file-title a:visited {
> text-decoration:none;}
>
> #yiv5874393226 div.yiv5874393226photo-title a,
> #yiv5874393226 div.yiv5874393226photo-title a:active,
> #yiv5874393226 div.yiv5874393226photo-title a:hover,
> #yiv5874393226 div.yiv5874393226photo-title a:visited {
> text-decoration:none;}
>
> #yiv5874393226 div#yiv5874393226ygrp-mlmsg
> #yiv5874393226ygrp-msg p a span.yiv5874393226yshortcuts {
> font-family:Verdana;font-size:10px;font-weight:normal;}
>
> #yiv5874393226 .yiv5874393226green {
> color:#628c2a;}
>
> #yiv5874393226 .yiv5874393226MsoNormal {
> margin:0 0 0 0;}
>
> #yiv5874393226 o {
> font-size:0;}
>
> #yiv5874393226 #yiv5874393226photos div {
> float:left;width:72px;}
>
> #yiv5874393226 #yiv5874393226photos div div {
> border:1px solid
> #666666;min-height:62px;overflow:hidden;width:62px;}
>
> #yiv5874393226 #yiv5874393226photos div label {
> color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}
>
> #yiv5874393226 #yiv5874393226reco-category {
> font-size:77%;}
>
> #yiv5874393226 #yiv5874393226reco-desc {
> font-size:77%;}
>
> #yiv5874393226 .yiv5874393226replbq {
> margin:4px;}
>
> #yiv5874393226 #yiv5874393226ygrp-actbar div a:first-child {
> margin-right:2px;padding-right:5px;}
>
> #yiv5874393226 #yiv5874393226ygrp-mlmsg {
> font-size:13px;font-family:Arial, helvetica, clean,
> sans-serif;}
>
> #yiv5874393226 #yiv5874393226ygrp-mlmsg table {
> font-size:inherit;font:100%;}
>
> #yiv5874393226 #yiv5874393226ygrp-mlmsg select,
> #yiv5874393226 input, #yiv5874393226 textarea {
> font:99% Arial, Helvetica, clean, sans-serif;}
>
> #yiv5874393226 #yiv5874393226ygrp-mlmsg pre, #yiv5874393226
> code {
> font:115% monospace;}
>
> #yiv5874393226 #yiv5874393226ygrp-mlmsg * {
> line-height:1.22em;}
>
> #yiv5874393226 #yiv5874393226ygrp-mlmsg #yiv5874393226logo {
> padding-bottom:10px;}
>
>
> #yiv5874393226 #yiv5874393226ygrp-msg p a {
> font-family:Verdana;}
>
> #yiv5874393226 #yiv5874393226ygrp-msg
> p#yiv5874393226attach-count span {
> color:#1E66AE;font-weight:700;}
>
> #yiv5874393226 #yiv5874393226ygrp-reco
> #yiv5874393226reco-head {
> color:#ff7900;font-weight:700;}
>
> #yiv5874393226 #yiv5874393226ygrp-reco {
> margin-bottom:20px;padding:0px;}
>
> #yiv5874393226 #yiv5874393226ygrp-sponsor #yiv5874393226ov
> li a {
> font-size:130%;text-decoration:none;}
>
> #yiv5874393226 #yiv5874393226ygrp-sponsor #yiv5874393226ov
> li {
> font-size:77%;list-style-type:square;padding:6px 0;}
>
> #yiv5874393226 #yiv5874393226ygrp-sponsor #yiv5874393226ov
> ul {
> margin:0;padding:0 0 0 8px;}
>
> #yiv5874393226 #yiv5874393226ygrp-text {
> font-family:Georgia;}
>
> #yiv5874393226 #yiv5874393226ygrp-text p {
> margin:0 0 1em 0;}
>
> #yiv5874393226 #yiv5874393226ygrp-text tt {
> font-size:120%;}
>
> #yiv5874393226 #yiv5874393226ygrp-vital ul li:last-child {
> border-right:none !important;
> }
> #yiv5874393226

Alan,

My comments about spray have to do with vent holes only. No spray, no problem.  If it is very warm inside when you bring the unit outside, you may get condensation. A vented box will equalize after a while.

Rain? What is rain? I live in Arizona. Can't help on wood treatment, the termites ate all of ours years ago.

BTW: Rainwater is not the same a distilled water. It contains whatever soluble contaminants that are present in the air, i.e. acid rain.

The polyurethane coating that I refer to is not a polish, it is a finish, like a varnish. Here is a link to the type of product that I am talking about. I offer this as an example, I have not used this particular material:

http://www.lowes.com/pd/Minwax-Fast-Drying-Polyurethane-Semi-Gloss-Base-11-5-fl-oz-Polyurethane/999913669

Leaded solder contains tin, but a lead content of 3% or greater eliminates the whiskers. You should be able to find that info on the NASA website. This is the problem with the ROHS directive being in absolutes. A mere pinch of lead would do away with the whisker problem in it's entirety.

I am not familiar with the Liquid Tin product, but if it leaves any elemental tin (not oxide), then it can be a source of whiskers. I suspect that this is the same thing that the industry calls immersion tin.  That process is a chemical replacement where the liquid is a tin salt, and the reaction exchanges the copper for tin, leaving elemental tin on the surface, with the copper going into solution as a copper salt. Clean copper quickly oxidizes, making soldering to the board difficult to impossible. The purpose of immersion tin is to keep the surface solderable when the board is not immediately used. It is an identified source of whiskers. http://www.epectec.com/articles/pcb-surface-finish-advantages-and-disadvantages.html

 

Thanks, Brad.   I watched the NASA video.

No, Harvey A., my circuit has no glass diodes, or other components that I know to contain glass.

I am glad you mentioned condensation, as I had never thought of
it occuring on my circuit board.    Having just defrosted my freezer yester
day, I  know it grows quickly on cold surfaces.    Since my circuit con-
troller will always be outdoors while in use, I will keep it inside when
not in use, so that condensation doesn't happen.    Nonetheless, I will inspect the PCB for condensation when the outdoor temperature drops.   The only "spray" the box might be subjected to is rain, which is distilled water.   The box will be on my screened-in wooden porch.  The porch was built with pressure-treated wood many years ago, but for the past several years moss has been growing on the wood, which should tell you how damp it is. (Another project--re-waterproofing the wooden porch.!   Will probably need another recommendation for treating that wood too, but email me privately for that.)

Okay, copper oxidation won't degrade the circuit's performance.

What about tin oxide?   Does either Liquid-Tin coating or leaded
solder contain tin?   If yes, do you think tin oxide will degrade the circuit's
performance ?   Or is too "self-limiting" and of no consequence?

I am not sure what you meant by the "Polyurethane wood polish" you recommend.   I am trying to identify a furniture polish containing polyurethane.   So far, I am only finding furniture polishes designed for wood furniture that has a top coat of polyurethane, like the one on your local tavern's wooden bar top.   I'm not sure whether to look for a furniture polish that was designed to be applied to a polyurethane top coat, or that actually contains polyurethane as listed in the ingredients.   Or are they one and the same?    As you can tell, I am pretty much ignorant about this product.   I am guessing its purpose is to fill in surface scratches on a polyurethane top coat.

73 to all.

Poisoning Pigeons in the Park is by Tom Lehrer

 

On Sun, 31 Jul 2016 17:48:40 +0000 (UTC), you wrote:

>Harvey
>
>For toasted sandwhiches..............
>Otherwise, hold the crust and feed that to the pesky Pigeons or Grey Squirrels.

Especially after you solder something?

reminds me of "poisoning pigeons in the park", I think by Spike Lee..

Harvey

>
>Malcolm
>
>I don't suffer from insanity I enjoy it!
>Mene, mene, tekel, upharsin
>The writing is on the wall.
>Ha-ktovet al ha-kir
>
>--------------------------------------------
>On Sun, 7/31/16, Harvey White madyn@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
>
> Subject: Re: [Homebrew_PCBs] Preventing oxidation of copper outdoors
> To: Homebrew_PCBs@yahoogroups.com
> Date: Sunday, July 31, 2016, 4:10 PM
>
>
>  
>
>
>
>
>
>
>
>
>
> On Sun, 31 Jul 2016 14:27:19 +0000 (UTC), you
> wrote:
>
>
>
> >Alan
>
> >
>
> >I use a knife and fork to eat my food, not my hands.....
> ;~)
>
>
>
> What, including sandwiches?
>
>
>
> Harvey
>
>
>
> >
>
> >Malcolm
>
> >
>
> >I don't suffer from insanity I enjoy it!
>
> >Mene, mene, tekel, upharsin
>
> >The writing is on the wall.
>
> >Ha-ktovet al ha-kir
>
> >
>
> >--------------------------------------------
>
> >On Sun, 7/31/16, alan00463@... [Homebrew_PCBs]
> <Homebrew_PCBs@yahoogroups.com> wrote:
>
> >
>
> > Subject: Re: [Homebrew_PCBs] Preventing oxidation of
> copper outdoors
>
> > To: Homebrew_PCBs@yahoogroups.com
>
> > Date: Sunday, July 31, 2016, 3:47 AM
>
> >
>
> >
>
> >  
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> > I use leaded solder too, Harvey. W.    Which
> is
>
> > why I wash my hands after soldering before eating.
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> > #yiv9500515032 #yiv9500515032 --
>
> > #yiv9500515032ygrp-mkp {
>
> > border:1px solid
> #d8d8d8;font-family:Arial;margin:10px
>
> > 0;padding:0 10px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mkp hr {
>
> > border:1px solid #d8d8d8;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mkp #yiv9500515032hd
> {
>
> >
> color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px
>
> > 0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mkp #yiv9500515032ads
> {
>
> > margin-bottom:10px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad
> {
>
> > padding:0 0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad
> p {
>
> > margin:0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mkp .yiv9500515032ad
> a {
>
> > color:#0000ff;text-decoration:none;}
>
> > #yiv9500515032 #yiv9500515032ygrp-sponsor
>
> > #yiv9500515032ygrp-lc {
>
> > font-family:Arial;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-sponsor
>
> > #yiv9500515032ygrp-lc #yiv9500515032hd {
>
> > margin:10px
>
> > 0px;font-weight:700;font-size:78%;line-height:122%;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-sponsor
>
> > #yiv9500515032ygrp-lc .yiv9500515032ad {
>
> > margin-bottom:10px;padding:0 0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032actions {
>
> > font-family:Verdana;font-size:11px;padding:10px 0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032activity {
>
> >
> background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032activity span {
>
> > font-weight:700;}
>
> >
>
> > #yiv9500515032 #yiv9500515032activity span:first-child
> {
>
> > text-transform:uppercase;}
>
> >
>
> > #yiv9500515032 #yiv9500515032activity span a {
>
> > color:#5085b6;text-decoration:none;}
>
> >
>
> > #yiv9500515032 #yiv9500515032activity span span {
>
> > color:#ff7900;}
>
> >
>
> > #yiv9500515032 #yiv9500515032activity span
>
> > .yiv9500515032underline {
>
> > text-decoration:underline;}
>
> >
>
> > #yiv9500515032 .yiv9500515032attach {
>
> >
> clear:both;display:table;font-family:Arial;font-size:12px;padding:10px
>
> > 0;width:400px;}
>
> >
>
> > #yiv9500515032 .yiv9500515032attach div a {
>
> > text-decoration:none;}
>
> >
>
> > #yiv9500515032 .yiv9500515032attach img {
>
> > border:none;padding-right:5px;}
>
> >
>
> > #yiv9500515032 .yiv9500515032attach label {
>
> > display:block;margin-bottom:5px;}
>
> >
>
> > #yiv9500515032 .yiv9500515032attach label a {
>
> > text-decoration:none;}
>
> >
>
> > #yiv9500515032 blockquote {
>
> > margin:0 0 0 4px;}
>
> >
>
> > #yiv9500515032 .yiv9500515032bold {
>
> > font-family:Arial;font-size:13px;font-weight:700;}
>
> >
>
> > #yiv9500515032 .yiv9500515032bold a {
>
> > text-decoration:none;}
>
> >
>
> > #yiv9500515032 dd.yiv9500515032last p a {
>
> > font-family:Verdana;font-weight:700;}
>
> >
>
> > #yiv9500515032 dd.yiv9500515032last p span {
>
> >
> margin-right:10px;font-family:Verdana;font-weight:700;}
>
> >
>
> > #yiv9500515032 dd.yiv9500515032last p
>
> > span.yiv9500515032yshortcuts {
>
> > margin-right:0;}
>
> >
>
> > #yiv9500515032 div.yiv9500515032attach-table div div a
> {
>
> > text-decoration:none;}
>
> >
>
> > #yiv9500515032 div.yiv9500515032attach-table {
>
> > width:400px;}
>
> >
>
> > #yiv9500515032 div.yiv9500515032file-title a,
> #yiv9500515032
>
> > div.yiv9500515032file-title a:active, #yiv9500515032
>
> > div.yiv9500515032file-title a:hover, #yiv9500515032
>
> > div.yiv9500515032file-title a:visited {
>
> > text-decoration:none;}
>
> >
>
> > #yiv9500515032 div.yiv9500515032photo-title a,
>
> > #yiv9500515032 div.yiv9500515032photo-title
> a:active,
>
> > #yiv9500515032 div.yiv9500515032photo-title a:hover,
>
> > #yiv9500515032 div.yiv9500515032photo-title a:visited
> {
>
> > text-decoration:none;}
>
> >
>
> > #yiv9500515032 div#yiv9500515032ygrp-mlmsg
>
> > #yiv9500515032ygrp-msg p a span.yiv9500515032yshortcuts
> {
>
> >
> font-family:Verdana;font-size:10px;font-weight:normal;}
>
> >
>
> > #yiv9500515032 .yiv9500515032green {
>
> > color:#628c2a;}
>
> >
>
> > #yiv9500515032 .yiv9500515032MsoNormal {
>
> > margin:0 0 0 0;}
>
> >
>
> > #yiv9500515032 o {
>
> > font-size:0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032photos div {
>
> > float:left;width:72px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032photos div div {
>
> > border:1px solid
>
> > #666666;min-height:62px;overflow:hidden;width:62px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032photos div label {
>
> >
> color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032reco-category {
>
> > font-size:77%;}
>
> >
>
> > #yiv9500515032 #yiv9500515032reco-desc {
>
> > font-size:77%;}
>
> >
>
> > #yiv9500515032 .yiv9500515032replbq {
>
> > margin:4px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-actbar div
> a:first-child {
>
> > margin-right:2px;padding-right:5px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mlmsg {
>
> > font-size:13px;font-family:Arial, helvetica, clean,
>
> > sans-serif;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mlmsg table {
>
> > font-size:inherit;font:100%;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mlmsg select,
>
> > #yiv9500515032 input, #yiv9500515032 textarea {
>
> > font:99% Arial, Helvetica, clean, sans-serif;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mlmsg pre,
> #yiv9500515032
>
> > code {
>
> > font:115% monospace;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mlmsg * {
>
> > line-height:1.22em;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-mlmsg
> #yiv9500515032logo {
>
> > padding-bottom:10px;}
>
> >
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-msg p a {
>
> > font-family:Verdana;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-msg
>
> > p#yiv9500515032attach-count span {
>
> > color:#1E66AE;font-weight:700;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-reco
>
> > #yiv9500515032reco-head {
>
> > color:#ff7900;font-weight:700;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-reco {
>
> > margin-bottom:20px;padding:0px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-sponsor
> #yiv9500515032ov
>
> > li a {
>
> > font-size:130%;text-decoration:none;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-sponsor
> #yiv9500515032ov
>
> > li {
>
> > font-size:77%;list-style-type:square;padding:6px 0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-sponsor
> #yiv9500515032ov
>
> > ul {
>
> > margin:0;padding:0 0 0 8px;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-text {
>
> > font-family:Georgia;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-text p {
>
> > margin:0 0 1em 0;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-text tt {
>
> > font-size:120%;}
>
> >
>
> > #yiv9500515032 #yiv9500515032ygrp-vital ul
> li:last-child {
>
> > border-right:none !important;
>
> > }
>
> > #yiv9500515032
>
>
>
>
>
>
>
>
>
>
>
>
>
> #yiv5874393226 #yiv5874393226 --
> #yiv5874393226ygrp-mkp {
> border:1px solid #d8d8d8;font-family:Arial;margin:10px
> 0;padding:0 10px;}
>
> #yiv5874393226 #yiv5874393226ygrp-mkp hr {
> border:1px solid #d8d8d8;}
>
> #yiv5874393226 #yiv5874393226ygrp-mkp #yiv5874393226hd {
> color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px
> 0;}
>
> #yiv5874393226 #yiv5874393226ygrp-mkp #yiv5874393226ads {
> margin-bottom:10px;}
>
> #yiv5874393226 #yiv5874393226ygrp-mkp .yiv5874393226ad {
> padding:0 0;}
>
> #yiv5874393226 #yiv5874393226ygrp-mkp .yiv5874393226ad p {
> margin:0;}
>
> #yiv5874393226 #yiv5874393226ygrp-mkp .yiv5874393226ad a {
> color:#0000ff;text-decoration:none;}
> #yiv5874393226 #yiv5874393226ygrp-sponsor
> #yiv5874393226ygrp-lc {
> font-family:Arial;}
>
> #yiv5874393226 #yiv5874393226ygrp-sponsor
> #yiv5874393226ygrp-lc #yiv5874393226hd {
> margin:10px
> 0px;font-weight:700;font-size:78%;line-height:122%;}
>
> #yiv5874393226 #yiv5874393226ygrp-sponsor
> #yiv5874393226ygrp-lc .yiv5874393226ad {
> margin-bottom:10px;padding:0 0;}
>
> #yiv5874393226 #yiv5874393226actions {
> font-family:Verdana;font-size:11px;padding:10px 0;}
>
> #yiv5874393226 #yiv5874393226activity {
> background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}
>
> #yiv5874393226 #yiv5874393226activity span {
> font-weight:700;}
>
> #yiv5874393226 #yiv5874393226activity span:first-child {
> text-transform:uppercase;}
>
> #yiv5874393226 #yiv5874393226activity span a {
> color:#5085b6;text-decoration:none;}
>
> #yiv5874393226 #yiv5874393226activity span span {
> color:#ff7900;}
>
> #yiv5874393226 #yiv5874393226activity span
> .yiv5874393226underline {
> text-decoration:underline;}
>
> #yiv5874393226 .yiv5874393226attach {
> clear:both;display:table;font-family:Arial;font-size:12px;padding:10px
> 0;width:400px;}
>
> #yiv5874393226 .yiv5874393226attach div a {
> text-decoration:none;}
>
> #yiv5874393226 .yiv5874393226attach img {
> border:none;padding-right:5px;}
>
> #yiv5874393226 .yiv5874393226attach label {
> display:block;margin-bottom:5px;}
>
> #yiv5874393226 .yiv5874393226attach label a {
> text-decoration:none;}
>
> #yiv5874393226 blockquote {
> margin:0 0 0 4px;}
>
> #yiv5874393226 .yiv5874393226bold {
> font-family:Arial;font-size:13px;font-weight:700;}
>
> #yiv5874393226 .yiv5874393226bold a {
> text-decoration:none;}
>
> #yiv5874393226 dd.yiv5874393226last p a {
> font-family:Verdana;font-weight:700;}
>
> #yiv5874393226 dd.yiv5874393226last p span {
> margin-right:10px;font-family:Verdana;font-weight:700;}
>
> #yiv5874393226 dd.yiv5874393226last p
> span.yiv5874393226yshortcuts {
> margin-right:0;}
>
> #yiv5874393226 div.yiv5874393226attach-table div div a {
> text-decoration:none;}
>
> #yiv5874393226 div.yiv5874393226attach-table {
> width:400px;}
>
> #yiv5874393226 div.yiv5874393226file-title a, #yiv5874393226
> div.yiv5874393226file-title a:active, #yiv5874393226
> div.yiv5874393226file-title a:hover, #yiv5874393226
> div.yiv5874393226file-title a:visited {
> text-decoration:none;}
>
> #yiv5874393226 div.yiv5874393226photo-title a,
> #yiv5874393226 div.yiv5874393226photo-title a:active,
> #yiv5874393226 div.yiv5874393226photo-title a:hover,
> #yiv5874393226 div.yiv5874393226photo-title a:visited {
> text-decoration:none;}
>
> #yiv5874393226 div#yiv5874393226ygrp-mlmsg
> #yiv5874393226ygrp-msg p a span.yiv5874393226yshortcuts {
> font-family:Verdana;font-size:10px;font-weight:normal;}
>
> #yiv5874393226 .yiv5874393226green {
> color:#628c2a;}
>
> #yiv5874393226 .yiv5874393226MsoNormal {
> margin:0 0 0 0;}
>
> #yiv5874393226 o {
> font-size:0;}
>
> #yiv5874393226 #yiv5874393226photos div {
> float:left;width:72px;}
>
> #yiv5874393226 #yiv5874393226photos div div {
> border:1px solid
> #666666;min-height:62px;overflow:hidden;width:62px;}
>
> #yiv5874393226 #yiv5874393226photos div label {
> color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}
>
> #yiv5874393226 #yiv5874393226reco-category {
> font-size:77%;}
>
> #yiv5874393226 #yiv5874393226reco-desc {
> font-size:77%;}
>
> #yiv5874393226 .yiv5874393226replbq {
> margin:4px;}
>
> #yiv5874393226 #yiv5874393226ygrp-actbar div a:first-child {
> margin-right:2px;padding-right:5px;}
>
> #yiv5874393226 #yiv5874393226ygrp-mlmsg {
> font-size:13px;font-family:Arial, helvetica, clean,
> sans-serif;}
>
> #yiv5874393226 #yiv5874393226ygrp-mlmsg table {
> font-size:inherit;font:100%;}
>
> #yiv5874393226 #yiv5874393226ygrp-mlmsg select,
> #yiv5874393226 input, #yiv5874393226 textarea {
> font:99% Arial, Helvetica, clean, sans-serif;}
>
> #yiv5874393226 #yiv5874393226ygrp-mlmsg pre, #yiv5874393226
> code {
> font:115% monospace;}
>
> #yiv5874393226 #yiv5874393226ygrp-mlmsg * {
> line-height:1.22em;}
>
> #yiv5874393226 #yiv5874393226ygrp-mlmsg #yiv5874393226logo {
> padding-bottom:10px;}
>
>
> #yiv5874393226 #yiv5874393226ygrp-msg p a {
> font-family:Verdana;}
>
> #yiv5874393226 #yiv5874393226ygrp-msg
> p#yiv5874393226attach-count span {
> color:#1E66AE;font-weight:700;}
>
> #yiv5874393226 #yiv5874393226ygrp-reco
> #yiv5874393226reco-head {
> color:#ff7900;font-weight:700;}
>
> #yiv5874393226 #yiv5874393226ygrp-reco {
> margin-bottom:20px;padding:0px;}
>
> #yiv5874393226 #yiv5874393226ygrp-sponsor #yiv5874393226ov
> li a {
> font-size:130%;text-decoration:none;}
>
> #yiv5874393226 #yiv5874393226ygrp-sponsor #yiv5874393226ov
> li {
> font-size:77%;list-style-type:square;padding:6px 0;}
>
> #yiv5874393226 #yiv5874393226ygrp-sponsor #yiv5874393226ov
> ul {
> margin:0;padding:0 0 0 8px;}
>
> #yiv5874393226 #yiv5874393226ygrp-text {
> font-family:Georgia;}
>
> #yiv5874393226 #yiv5874393226ygrp-text p {
> margin:0 0 1em 0;}
>
> #yiv5874393226 #yiv5874393226ygrp-text tt {
> font-size:120%;}
>
> #yiv5874393226 #yiv5874393226ygrp-vital ul li:last-child {
> border-right:none !important;
> }
> #yiv5874393226

>
> On Sun, 31 Jul 2016 17:48:40 +0000 (UTC), you wrote:
>
> >Harvey
> >
> >For toasted sandwhiches..............
> >Otherwise, hold the crust and feed that to the pesky Pigeons or Grey
> Squirrels.
>
> Especially after you solder something?
>
> reminds me of "poisoning pigeons in the park", I think by Spike Lee..
>

>Alan,
>
>My comments about spray have to do with vent holes only. No spray, no
>problem. If it is very warm inside when you bring the unit outside, you
>may get condensation. A vented box will equalize after a while.
>
>Rain? What is rain? I live in Arizona. Can't help on wood treatment, the
>termites ate all of ours years ago.
>
>BTW: Rainwater is not the same a distilled water. It contains whatever
>soluble contaminants that are present in the air, i.e. acid rain.
>
>The polyurethane coating that I refer to is not a polish, it is a
>finish, like a varnish. Here is a link to the type of product that I am
>talking about. I offer this as an example, I have not used this
>particular material:
>
>http://www.lowes.com/pd/Minwax-Fast-Drying-Polyurethane-Semi-Gloss-Base-11-5-fl-oz-Polyurethane/999913669
>
>Leaded solder contains tin, but a lead content of 3% or greater
>eliminates the whiskers. You should be able to find that info on the
>NASA website. This is the problem with the ROHS directive being in
>absolutes. A mere pinch of lead would do away with the whisker problem
>in it's entirety.
>
>I am not familiar with the Liquid Tin product, but if it leaves any
>elemental tin (not oxide), then it can be a source of whiskers. I
>suspect that this is the same thing that the industry calls immersion
>tin. That process is a chemical replacement where the liquid is a tin
>salt, and the reaction exchanges the copper for tin, leaving elemental
>tin on the surface, with the copper going into solution as a copper
>salt. Clean copper quickly oxidizes, making soldering to the board
>difficult to impossible. The purpose of immersion tin is to keep the
>surface solderable when the board is not immediately used. It is an
>identified source of whiskers.
>http://www.epectec.com/articles/pcb-surface-finish-advantages-and-disadvantages.html
>
>I hope this answers all your questions.

>
>Harvey
>On 7/31/2016 9:48 AM, alan00463@... [Homebrew_PCBs] wrote:
>>
>> Thanks, Brad. I watched the NASA video.
>>
>> No, Harvey A., my circuit has no glass diodes, or other components
>> that I know to contain glass.
>>
>> I am glad you mentioned condensation, as I had never thought of
>> it occuring on my circuit board. Having just defrosted my freezer
>> yester
>> day, I know it grows quickly on cold surfaces. Since my circuit con-
>> troller will always be outdoors while in use, I will keep it inside when
>> not in use, so that condensation doesn't happen. Nonetheless, I will
>> inspect the PCB for condensation when the outdoor temperature drops.
>> The only "spray" the box might be subjected to is rain, which is
>> distilled water. The box will be on my screened-in wooden porch. The
>> porch was built with pressure-treated wood many years ago, but for the
>> past several years moss has been growing on the wood, which should
>> tell you how damp it is. (Another project--re-waterproofing the wooden
>> porch.! Will probably need another recommendation for treating that
>> wood too, but email me privately for that.)
>>
>> Okay, copper oxidation won't degrade the circuit's performance.
>>
>> What about tin oxide? Does either Liquid-Tin coating or leaded
>> solder contain tin? If yes, do you think tin oxide will degrade the
>> circuit's
>> performance ? Or is too "self-limiting" and of no consequence?
>>
>> I am not sure what you meant by the "Polyurethane wood polish" you
>> recommend. I am trying to identify a furniture polish containing
>> polyurethane. So far, I am only finding furniture polishes designed
>> for wood furniture that has a top coat of polyurethane, like the one
>> on your local tavern's wooden bar top. I'm not sure whether to look
>> for a furniture polish that was designed to be applied to a
>> polyurethane top coat, or that actually contains polyurethane as
>> listed in the ingredients. Or are they one and the same? As you
>> can tell, I am pretty much ignorant about this product. I am
>> guessing its purpose is to fill in surface scratches on a polyurethane
>> top coat.
>>
>> 73 to all.
>>
>>

>RoHS allows 0.1% lead.
>
>I think this Liquid Tin is based on thiourea, something much, much worse
>than lead. Remember to wash your hands and wear a hardhat or something ;-).

>
>ST
>
>On Sun, Jul 31, 2016 at 9:37 PM, Harvey Altstadter hrconsult@...
>[Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
>
>>
>> This is the problem with the ROHS directive being in absolutes. A mere
>> pinch of lead would do away with the whisker problem in it's entirety.
>>
>> I am not familiar with the Liquid Tin product, but if it leaves any
>> elemental tin (not oxide), then it can be a source of whiskers. I suspect
>> that this is the same thing that the industry calls immersion tin. That
>> process is a chemical replacement where the liquid is a tin salt, and the
>> reaction exchanges the copper for tin, leaving elemental tin on the
>> surface, with the copper going into solution as a copper salt. Clean copper
>> quickly oxidizes, making soldering to the board difficult to impossible.
>> The purpose of immersion tin is to keep the surface solderable when the
>> board is not immediately used. It is an identified source of whiskers.
>> http://www.epectec.com/articles/pcb-surface-finish-advantages-and-disadvantages.html
>> I hope this answers all your questions.
>>
>> Harvey
>> On 7/31/2016 9:48 AM, alan00463@... [Homebrew_PCBs] wrote:
>>
>>
>>
>> Thanks, Brad. I watched the NASA video.
>>
>> No, Harvey A., my circuit has no glass diodes, or other components that I
>> know to contain glass.
>>
>> I am glad you mentioned condensation, as I had never thought of
>> it occuring on my circuit board. Having just defrosted my freezer yester
>> day, I know it grows quickly on cold surfaces. Since my circuit con-
>> troller will always be outdoors while in use, I will keep it inside when
>> not in use, so that condensation doesn't happen. Nonetheless, I will
>> inspect the PCB for condensation when the outdoor temperature drops. The
>> only "spray" the box might be subjected to is rain, which is distilled
>> water. The box will be on my screened-in wooden porch. The porch was
>> built with pressure-treated wood many years ago, but for the past several
>> years moss has been growing on the wood, which should tell you how damp it
>> is. (Another project--re-waterproofing the wooden porch.! Will probably
>> need another recommendation for treating that wood too, but email me
>> privately for that.)
>>
>> Okay, copper oxidation won't degrade the circuit's performance.
>>
>> What about tin oxide? Does either Liquid-Tin coating or leaded
>> solder contain tin? If yes, do you think tin oxide will degrade the
>> circuit's
>> performance ? Or is too "self-limiting" and of no consequence?
>>
>> I am not sure what you meant by the "Polyurethane wood polish" you
>> recommend. I am trying to identify a furniture polish containing
>> polyurethane. So far, I am only finding furniture polishes designed for
>> wood furniture that has a top coat of polyurethane, like the one on your
>> local tavern's wooden bar top. I'm not sure whether to look for a
>> furniture polish that was designed to be applied to a polyurethane top
>> coat, or that actually contains polyurethane as listed in the
>> ingredients. Or are they one and the same? As you can tell, I am
>> pretty much ignorant about this product. I am guessing its purpose is to
>> fill in surface scratches on a polyurethane top coat.
>>
>> 73 to all.
>>
>>
>>
>>
>>

Harvey,

The name HASL is appropriate because it is a hassle. It requires special equipment. The boards are first solder dipped, and then passed between hot air knives, where the air is hot enough to reflow the solder. The excess solder is blown off, leaving a thin coating of solder on the board. I suppose that this could be approximated by a hot plate and a heat gun with a flat funnel type adapter on the front. Might work.  This could leave slivers of solder bridging some of the traces.

I my early days in the Aerospace Industry, we would solder coat the boards by solder plating them, and then reflowing the plated solder by floating the boards on hot peanut oil. A rather sloppy process. 

The other Harvey

 

On Mon, 1 Aug 2016 05:45:53 +0200, you wrote:

>RoHS allows 0.1% lead.
>
>I think this Liquid Tin is based on thiourea, something much, much worse
>than lead. Remember to wash your hands and wear a hardhat or something ;-).

I think it is. It comes with lots of warnings, most of which involve
the word "poison".

I use gloves and tongs, and wash the boards thoroughly. Also, this is
done quite outside the house.

Wonder if I could do something like HASL....

Harvey

>
>ST
>
>On Sun, Jul 31, 2016 at 9:37 PM, Harvey Altstadter hrconsult@...
>[Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
>
>>
>> This is the problem with the ROHS directive being in absolutes. A mere
>> pinch of lead would do away with the whisker problem in it's entirety.
>>
>> I am not familiar with the Liquid Tin product, but if it leaves any
>> elemental tin (not oxide), then it can be a source of whiskers. I suspect
>> that this is the same thing that the industry calls immersion tin. That
>> process is a chemical replacement where the liquid is a tin salt, and the
>> reaction exchanges the copper for tin, leaving elemental tin on the
>> surface, with the copper going into solution as a copper salt. Clean copper
>> quickly oxidizes, making soldering to the board difficult to impossible.
>> The purpose of immersion tin is to keep the surface solderable when the
>> board is not immediately used. It is an identified source of whiskers.
>> http://www.epectec.com/articles/pcb-surface-finish-advantages-and-disadvantages.html
>> I hope this answers all your questions.
>>
>> Harvey
>> On 7/31/2016 9:48 AM, alan00463@... [Homebrew_PCBs] wrote:
>>
>>
>>
>> Thanks, Brad. I watched the NASA video.
>>
>> No, Harvey A., my circuit has no glass diodes, or other components that I
>> know to contain glass.
>>
>> I am glad you mentioned condensation, as I had never thought of
>> it occuring on my circuit board. Having just defrosted my freezer yester
>> day, I know it grows quickly on cold surfaces. Since my circuit con-
>> troller will always be outdoors while in use, I will keep it inside when
>> not in use, so that condensation doesn't happen. Nonetheless, I will
>> inspect the PCB for condensation when the outdoor temperature drops. The
>> only "spray" the box might be subjected to is rain, which is distilled
>> water. The box will be on my screened-in wooden porch. The porch was
>> built with pressure-treated wood many years ago, but for the past several
>> years moss has been growing on the wood, which should tell you how damp it
>> is. (Another project--re-waterproofing the wooden porch.! Will probably
>> need another recommendation for treating that wood too, but email me
>> privately for that.)
>>
>> Okay, copper oxidation won't degrade the circuit's performance.
>>
>> What about tin oxide? Does either Liquid-Tin coating or leaded
>> solder contain tin? If yes, do you think tin oxide will degrade the
>> circuit's
>> performance ? Or is too "self-limiting" and of no consequence?
>>
>> I am not sure what you meant by the "Polyurethane wood polish" you
>> recommend. I am trying to identify a furniture polish containing
>> polyurethane. So far, I am only finding furniture polishes designed for
>> wood furniture that has a top coat of polyurethane, like the one on your
>> local tavern's wooden bar top. I'm not sure whether to look for a
>> furniture polish that was designed to be applied to a polyurethane top
>> coat, or that actually contains polyurethane as listed in the
>> ingredients. Or are they one and the same? As you can tell, I am
>> pretty much ignorant about this product. I am guessing its purpose is to
>> fill in surface scratches on a polyurethane top coat.
>>
>> 73 to all.
>>
>>
>>
>>
>>

> On Mon, 1 Aug 2016 05:45:53 +0200, you wrote:
>
>>RoHS allows 0.1% lead.
>>
>>I think this Liquid Tin is based on thiourea, something much, much worse
>>than lead. Remember to wash your hands and wear a hardhat or something ;-).
>
> I think it is. It comes with lots of warnings, most of which involve
> the word "poison".
>
> I use gloves and tongs, and wash the boards thoroughly. Also, this is
> done quite outside the house.
>
> Wonder if I could do something like HASL....
>
>
> Harvey
>

>There you go again, poisoning the squirrels.
>
>I did something much like HASL when I still made boards, what you can
>do is you buy a can of plumbing solder paste (the solder bearing
>kind). This is tin only solder so you don't need to worry about the
>waste, and it's much cheaper than SMT solder paste for electronics.
>Then you dilute it to a consistency you can paint with a brush, just
>with water. Paint that on your board, heat with air gun to reflow. The
>excess on bare surfaces just washes off.
>This leaves a pock-marked matte surface, if you want it smooth and
>shiny you can wipe off the excess with a paper towel while still hot.
>Does the same as air leveling but much more practical at home.
>Mind to wash the flux off well, since it is not electronics flux. It
>is water soluble since it is designed for plumbing and hot water takes
>it right off.

>
>I briefly considered building a roller tinning machine, basically two
>rollers between which the PCB is fed, with the lower out of metal and
>immersed in a solder bath at the bottom. The whole thing is heated and
>you just feed the board through. I was told it works fine but keeping
>the solder bath free of dross is a bit of a pain, requiring special
>flux. You can find pictures with google, they are used commercially.

>
>That said, the vast majority of boards I simply coated in colophony
>resin (rosin) flux. This is so mild it doesn't cause corrosion, and
>with denatured alcohol (ethanol) it can be made into a nice laquer.
>Since it is a flux it is great to solder and protects the copper from
>oxidation for a long time. They even make a spray can so you don't
>need to mess with the sticky paintbrush.
>

>ST
>
>On Mon, Aug 1, 2016 at 6:06 AM, Harvey White madyn@...
>[Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
>> On Mon, 1 Aug 2016 05:45:53 +0200, you wrote:
>>
>>>RoHS allows 0.1% lead.
>>>
>>>I think this Liquid Tin is based on thiourea, something much, much worse
>>>than lead. Remember to wash your hands and wear a hardhat or something ;-).
>>
>> I think it is. It comes with lots of warnings, most of which involve
>> the word "poison".
>>
>> I use gloves and tongs, and wash the boards thoroughly. Also, this is
>> done quite outside the house.
>>
>> Wonder if I could do something like HASL....
>>
>>
>> Harvey
>>

> On Mon, 1 Aug 2016 06:50:27 +0200, you wrote:
>
>>There you go again, poisoning the squirrels.
>>
>>I did something much like HASL when I still made boards, what you can
>>do is you buy a can of plumbing solder paste (the solder bearing
>>kind). This is tin only solder so you don't need to worry about the
>>waste, and it's much cheaper than SMT solder paste for electronics.
>>Then you dilute it to a consistency you can paint with a brush, just
>>with water. Paint that on your board, heat with air gun to reflow. The
>>excess on bare surfaces just washes off.
>>This leaves a pock-marked matte surface, if you want it smooth and
>>shiny you can wipe off the excess with a paper towel while still hot.
>>Does the same as air leveling but much more practical at home.
>>Mind to wash the flux off well, since it is not electronics flux. It
>>is water soluble since it is designed for plumbing and hot water takes
>>it right off.
>
> I may try this, it seems lots better than immersion tin. Right now,
> I'm in a software phase of development, much cheaper than making
> boards. Some boards are at the production phase, so I've got a design
> that works, I'll just possibly need more of them.
>
>>
>>I briefly considered building a roller tinning machine, basically two
>>rollers between which the PCB is fed, with the lower out of metal and
>>immersed in a solder bath at the bottom. The whole thing is heated and
>>you just feed the board through. I was told it works fine but keeping
>>the solder bath free of dross is a bit of a pain, requiring special
>>flux. You can find pictures with google, they are used commercially.
>
> Before I did something like that, (unlikely), I'd try to make a
> etchant system with a pump for more even etching. May end up with a
> peristaltic pump and silicone tubing.
>>
>>That said, the vast majority of boards I simply coated in colophony
>>resin (rosin) flux. This is so mild it doesn't cause corrosion, and
>>with denatured alcohol (ethanol) it can be made into a nice laquer.
>>Since it is a flux it is great to solder and protects the copper from
>>oxidation for a long time. They even make a spray can so you don't
>>need to mess with the sticky paintbrush.
>>
>
> Now that seems to be the simplest one, so that's on the list, too.
>
> Thanks for the suggestions:
>
> Harvey
>
>>ST
>>
>>On Mon, Aug 1, 2016 at 6:06 AM, Harvey White madyn@...
>>[Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
>>> On Mon, 1 Aug 2016 05:45:53 +0200, you wrote:
>>>
>>>>RoHS allows 0.1% lead.
>>>>
>>>>I think this Liquid Tin is based on thiourea, something much, much worse
>>>>than lead. Remember to wash your hands and wear a hardhat or something ;-).
>>>
>>> I think it is. It comes with lots of warnings, most of which involve
>>> the word "poison".
>>>
>>> I use gloves and tongs, and wash the boards thoroughly. Also, this is
>>> done quite outside the house.
>>>
>>> Wonder if I could do something like HASL....
>>>
>>>
>>> Harvey
>>>
>
>
>
> ------------------------------------
> Posted by: Harvey White <madyn@...>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBs
> ------------------------------------
>
> Yahoo Groups Links
>
>
>

>Harvey,
>
>The name HASL is appropriate because it is a hassle. It requires special
>equipment. The boards are first solder dipped, and then passed between
>hot air knives, where the air is hot enough to reflow the solder. The
>excess solder is blown off, leaving a thin coating of solder on the
>board. I suppose that this could be approximated by a hot plate and a
>heat gun with a flat funnel type adapter on the front. Might work. This
>could leave slivers of solder bridging some of the traces.

>
>I my early days in the Aerospace Industry, we would solder coat the
>boards by solder plating them, and then reflowing the plated solder by
>floating the boards on hot peanut oil. A rather sloppy process.

>
>The other Harvey
>
>
>On 7/31/2016 9:06 PM, Harvey White madyn@...
>[Homebrew_PCBs] wrote:
>>
>> On Mon, 1 Aug 2016 05:45:53 +0200, you wrote:
>>
>> >RoHS allows 0.1% lead.
>> >
>> >I think this Liquid Tin is based on thiourea, something much, much worse
>> >than lead. Remember to wash your hands and wear a hardhat or
>> something ;-).
>>
>> I think it is. It comes with lots of warnings, most of which involve
>> the word "poison".
>>
>> I use gloves and tongs, and wash the boards thoroughly. Also, this is
>> done quite outside the house.
>>
>> Wonder if I could do something like HASL....
>>
>> Harvey
>>
>> >
>> >ST
>> >
>> >On Sun, Jul 31, 2016 at 9:37 PM, Harvey Altstadter hrconsult@...
>> >[Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
>> >
>> >>
>> >> This is the problem with the ROHS directive being in absolutes. A mere
>> >> pinch of lead would do away with the whisker problem in it's entirety.
>> >>
>> >> I am not familiar with the Liquid Tin product, but if it leaves any
>> >> elemental tin (not oxide), then it can be a source of whiskers. I
>> suspect
>> >> that this is the same thing that the industry calls immersion tin. That
>> >> process is a chemical replacement where the liquid is a tin salt,
>> and the
>> >> reaction exchanges the copper for tin, leaving elemental tin on the
>> >> surface, with the copper going into solution as a copper salt.
>> Clean copper
>> >> quickly oxidizes, making soldering to the board difficult to
>> impossible.
>> >> The purpose of immersion tin is to keep the surface solderable when the
>> >> board is not immediately used. It is an identified source of whiskers.
>> >>
>> http://www.epectec.com/articles/pcb-surface-finish-advantages-and-disadvantages.html
>> >> I hope this answers all your questions.
>> >>
>> >> Harvey
>> >> On 7/31/2016 9:48 AM, alan00463@... [Homebrew_PCBs] wrote:
>> >>
>> >>
>> >>
>> >> Thanks, Brad. I watched the NASA video.
>> >>
>> >> No, Harvey A., my circuit has no glass diodes, or other components
>> that I
>> >> know to contain glass.
>> >>
>> >> I am glad you mentioned condensation, as I had never thought of
>> >> it occuring on my circuit board. Having just defrosted my freezer
>> yester
>> >> day, I know it grows quickly on cold surfaces. Since my circuit con-
>> >> troller will always be outdoors while in use, I will keep it inside
>> when
>> >> not in use, so that condensation doesn't happen. Nonetheless, I will
>> >> inspect the PCB for condensation when the outdoor temperature
>> drops. The
>> >> only "spray" the box might be subjected to is rain, which is distilled
>> >> water. The box will be on my screened-in wooden porch. The porch was
>> >> built with pressure-treated wood many years ago, but for the past
>> several
>> >> years moss has been growing on the wood, which should tell you how
>> damp it
>> >> is. (Another project--re-waterproofing the wooden porch.! Will probably
>> >> need another recommendation for treating that wood too, but email me
>> >> privately for that.)
>> >>
>> >> Okay, copper oxidation won't degrade the circuit's performance.
>> >>
>> >> What about tin oxide? Does either Liquid-Tin coating or leaded
>> >> solder contain tin? If yes, do you think tin oxide will degrade the
>> >> circuit's
>> >> performance ? Or is too "self-limiting" and of no consequence?
>> >>
>> >> I am not sure what you meant by the "Polyurethane wood polish" you
>> >> recommend. I am trying to identify a furniture polish containing
>> >> polyurethane. So far, I am only finding furniture polishes designed for
>> >> wood furniture that has a top coat of polyurethane, like the one on
>> your
>> >> local tavern's wooden bar top. I'm not sure whether to look for a
>> >> furniture polish that was designed to be applied to a polyurethane top
>> >> coat, or that actually contains polyurethane as listed in the
>> >> ingredients. Or are they one and the same? As you can tell, I am
>> >> pretty much ignorant about this product. I am guessing its purpose
>> is to
>> >> fill in surface scratches on a polyurethane top coat.
>> >>
>> >> 73 to all.
>> >>
>> >>
>> >>
>> >>
>> >>
>>
>>

> However, I like the idea of wiping
> off the melted solder with a pad (or perhaps brass sponge).
>
> I'd be worried about the process overheating the board myself,
> especially if the boards do not have plated through holes (and mine
> won't).
>

> a result of that. We might never know just how much damage Thomas
> Midgley actually did. Some of the damage is only apparent decades later (as
> with asbestos), and some is never discovered.

>> a result of that. We might never know just how much damage Thomas
>> Midgley actually did. Some of the damage is only apparent decades later (as
>> with asbestos), and some is never discovered.
>
>
> We need to build a giant statue of that dude, and let the pigeons crap all over it before we poison them.
>
> Then throw the dead pigeons at the statue.
>
> Tony
>
> (Ol' Tom's other great contribution to the planet was stuffing the ozone layer.)
>

On Wed, 8/3/16, Stefan Trethan stefan_trethan@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

Subject: Re: [Homebrew_PCBs] Preventing oxidation of copper outdoors
To: Homebrew_PCBs@yahoogroups.com
Date: Wednesday, August 3, 2016, 5:36 PM


 









To be fair to Mr. Midgley Jr., at least he did not
use arsenic instead

of lead, which according to his experiments also worked to
eliminate

knocking. ;-)



On a more serious note, you have to look at his inventions
while

keeping in mind what was known at the time. He was one of
those people

that just got the job done, even if the task was
considered

impossible, and no matter how many skills he had to learn in
the

process.



He invented leaded petrol to give the allied war planes an
edge, by

allowing more compression and more power. That was his task,
he

delivered a solution in time for WW2. Don't forget
nobody considered

lead dangerous then.



As for CFCs, he was faced with the task of finding a safer
refrigerant

that wouldn't kill everyone in the house if the freezer
leaked, again

he delivered. Nobody knew about this ozone layer thing back
then.



Read Charles Kettering's memoir and tell me you
wouldn't have loved to

work with the guy. One time, when he got metal splinters in
his eye

from an exploding tank, and the doctor couldn't get them
out, he

successfully dissolved them by bathing his eye in mercury. I
mean who

has an idea like that?



But there must have been a darker side to the man, one
Kettering

didn't touch on. When the workers got ill at the TEL
plant and he held

that stunt press conference, he must have known this was
unsafe. He

sure knew afterwards since he was sick as a dog from the
lead

poisoning, but I don't think he did anything to set the
record

straight.



I've always been suspicious about his accidental death.
A smart man,

getting tangled up in his own ropes like that, not sure if I
buy it.

Perhaps he was just tired of it all.



ST



On Wed, Aug 3, 2016 at 11:06 AM, 'Tony Smith'
ajsmith1968@...

[Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com>
wrote:

>> a result of that. We might never know just how much
damage Thomas

>> Midgley actually did. Some of the damage is only
apparent decades later (as

>> with asbestos), and some is never discovered.

>

>

> We need to build a giant statue of that dude, and let
the pigeons crap all over it before we poison them.

>

> Then throw the dead pigeons at the statue.

>

> Tony

>

> (Ol' Tom's other great contribution to the
planet was stuffing the ozone layer.)

>











#yiv7398866425 #yiv7398866425 --
#yiv7398866425ygrp-mkp {
border:1px solid #d8d8d8;font-family:Arial;margin:10px
0;padding:0 10px;}

#yiv7398866425 #yiv7398866425ygrp-mkp hr {
border:1px solid #d8d8d8;}

#yiv7398866425 #yiv7398866425ygrp-mkp #yiv7398866425hd {
color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px
0;}

#yiv7398866425 #yiv7398866425ygrp-mkp #yiv7398866425ads {
margin-bottom:10px;}

#yiv7398866425 #yiv7398866425ygrp-mkp .yiv7398866425ad {
padding:0 0;}

#yiv7398866425 #yiv7398866425ygrp-mkp .yiv7398866425ad p {
margin:0;}

#yiv7398866425 #yiv7398866425ygrp-mkp .yiv7398866425ad a {
color:#0000ff;text-decoration:none;}
#yiv7398866425 #yiv7398866425ygrp-sponsor
#yiv7398866425ygrp-lc {
font-family:Arial;}

#yiv7398866425 #yiv7398866425ygrp-sponsor
#yiv7398866425ygrp-lc #yiv7398866425hd {
margin:10px
0px;font-weight:700;font-size:78%;line-height:122%;}

#yiv7398866425 #yiv7398866425ygrp-sponsor
#yiv7398866425ygrp-lc .yiv7398866425ad {
margin-bottom:10px;padding:0 0;}

#yiv7398866425 #yiv7398866425actions {
font-family:Verdana;font-size:11px;padding:10px 0;}

#yiv7398866425 #yiv7398866425activity {
background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}

#yiv7398866425 #yiv7398866425activity span {
font-weight:700;}

#yiv7398866425 #yiv7398866425activity span:first-child {
text-transform:uppercase;}

#yiv7398866425 #yiv7398866425activity span a {
color:#5085b6;text-decoration:none;}

#yiv7398866425 #yiv7398866425activity span span {
color:#ff7900;}

#yiv7398866425 #yiv7398866425activity span
.yiv7398866425underline {
text-decoration:underline;}

#yiv7398866425 .yiv7398866425attach {
clear:both;display:table;font-family:Arial;font-size:12px;padding:10px
0;width:400px;}

#yiv7398866425 .yiv7398866425attach div a {
text-decoration:none;}

#yiv7398866425 .yiv7398866425attach img {
border:none;padding-right:5px;}

#yiv7398866425 .yiv7398866425attach label {
display:block;margin-bottom:5px;}

#yiv7398866425 .yiv7398866425attach label a {
text-decoration:none;}

#yiv7398866425 blockquote {
margin:0 0 0 4px;}

#yiv7398866425 .yiv7398866425bold {
font-family:Arial;font-size:13px;font-weight:700;}

#yiv7398866425 .yiv7398866425bold a {
text-decoration:none;}

#yiv7398866425 dd.yiv7398866425last p a {
font-family:Verdana;font-weight:700;}

#yiv7398866425 dd.yiv7398866425last p span {
margin-right:10px;font-family:Verdana;font-weight:700;}

#yiv7398866425 dd.yiv7398866425last p
span.yiv7398866425yshortcuts {
margin-right:0;}

#yiv7398866425 div.yiv7398866425attach-table div div a {
text-decoration:none;}

#yiv7398866425 div.yiv7398866425attach-table {
width:400px;}

#yiv7398866425 div.yiv7398866425file-title a, #yiv7398866425
div.yiv7398866425file-title a:active, #yiv7398866425
div.yiv7398866425file-title a:hover, #yiv7398866425
div.yiv7398866425file-title a:visited {
text-decoration:none;}

#yiv7398866425 div.yiv7398866425photo-title a,
#yiv7398866425 div.yiv7398866425photo-title a:active,
#yiv7398866425 div.yiv7398866425photo-title a:hover,
#yiv7398866425 div.yiv7398866425photo-title a:visited {
text-decoration:none;}

#yiv7398866425 div#yiv7398866425ygrp-mlmsg
#yiv7398866425ygrp-msg p a span.yiv7398866425yshortcuts {
font-family:Verdana;font-size:10px;font-weight:normal;}

#yiv7398866425 .yiv7398866425green {
color:#628c2a;}

#yiv7398866425 .yiv7398866425MsoNormal {
margin:0 0 0 0;}

#yiv7398866425 o {
font-size:0;}

#yiv7398866425 #yiv7398866425photos div {
float:left;width:72px;}

#yiv7398866425 #yiv7398866425photos div div {
border:1px solid
#666666;min-height:62px;overflow:hidden;width:62px;}

#yiv7398866425 #yiv7398866425photos div label {
color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}

#yiv7398866425 #yiv7398866425reco-category {
font-size:77%;}

#yiv7398866425 #yiv7398866425reco-desc {
font-size:77%;}

#yiv7398866425 .yiv7398866425replbq {
margin:4px;}

#yiv7398866425 #yiv7398866425ygrp-actbar div a:first-child {
margin-right:2px;padding-right:5px;}

#yiv7398866425 #yiv7398866425ygrp-mlmsg {
font-size:13px;font-family:Arial, helvetica, clean,
sans-serif;}

#yiv7398866425 #yiv7398866425ygrp-mlmsg table {
font-size:inherit;font:100%;}

#yiv7398866425 #yiv7398866425ygrp-mlmsg select,
#yiv7398866425 input, #yiv7398866425 textarea {
font:99% Arial, Helvetica, clean, sans-serif;}

#yiv7398866425 #yiv7398866425ygrp-mlmsg pre, #yiv7398866425
code {
font:115% monospace;}

#yiv7398866425 #yiv7398866425ygrp-mlmsg * {
line-height:1.22em;}

#yiv7398866425 #yiv7398866425ygrp-mlmsg #yiv7398866425logo {
padding-bottom:10px;}


#yiv7398866425 #yiv7398866425ygrp-msg p a {
font-family:Verdana;}

#yiv7398866425 #yiv7398866425ygrp-msg
p#yiv7398866425attach-count span {
color:#1E66AE;font-weight:700;}

#yiv7398866425 #yiv7398866425ygrp-reco
#yiv7398866425reco-head {
color:#ff7900;font-weight:700;}

#yiv7398866425 #yiv7398866425ygrp-reco {
margin-bottom:20px;padding:0px;}

#yiv7398866425 #yiv7398866425ygrp-sponsor #yiv7398866425ov
li a {
font-size:130%;text-decoration:none;}

#yiv7398866425 #yiv7398866425ygrp-sponsor #yiv7398866425ov
li {
font-size:77%;list-style-type:square;padding:6px 0;}

#yiv7398866425 #yiv7398866425ygrp-sponsor #yiv7398866425ov
ul {
margin:0;padding:0 0 0 8px;}

#yiv7398866425 #yiv7398866425ygrp-text {
font-family:Georgia;}

#yiv7398866425 #yiv7398866425ygrp-text p {
margin:0 0 1em 0;}

#yiv7398866425 #yiv7398866425ygrp-text tt {
font-size:120%;}

#yiv7398866425 #yiv7398866425ygrp-vital ul li:last-child {
border-right:none !important;
}
#yiv7398866425

> What I like about this group is I regularly learn something new, or something
> more about something I knew a little of..
>
> Malcolm

> Have a read up on Clair Patterson (a bloke, not a woman) who first figured out maybe lead in everything wasn't such a good idea. That started when he was a university, and one day his professor told him to go off and figure out how old the world was. "Piece of cake, what you do is..."
>

On Fri, 8/5/16, hitekgearhead@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

Subject: Technical History (Re: [Homebrew_PCBs] Preventing oxidation of copper outdoors)
To: Homebrew_PCBs@yahoogroups.com
Date: Friday, August 5, 2016, 2:08 PM


 









When I was in college, I of course, like everyone
else had to take history classes.

I share the same sentiment with you on the
subject.

I had a history
teacher that was only interested in the dates documents were
signed and by whom.

As a
young engineering student I thought it would be amazingly
inspiring to offer those students in the technical
disciplines a "technical history" class.

I would have been much more
inspired by learning about Tesla, Edison, Ford, Marconi,
Einstein, Fermi, etc, etc, etc. It would have brought so
much more life to the pages of integrals and matrices that
we were learning about in our physics and electronics
classes.

-Albert 









#yiv4282381662 #yiv4282381662 --
#yiv4282381662ygrp-mkp {
border:1px solid #d8d8d8;font-family:Arial;margin:10px
0;padding:0 10px;}

#yiv4282381662 #yiv4282381662ygrp-mkp hr {
border:1px solid #d8d8d8;}

#yiv4282381662 #yiv4282381662ygrp-mkp #yiv4282381662hd {
color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px
0;}

#yiv4282381662 #yiv4282381662ygrp-mkp #yiv4282381662ads {
margin-bottom:10px;}

#yiv4282381662 #yiv4282381662ygrp-mkp .yiv4282381662ad {
padding:0 0;}

#yiv4282381662 #yiv4282381662ygrp-mkp .yiv4282381662ad p {
margin:0;}

#yiv4282381662 #yiv4282381662ygrp-mkp .yiv4282381662ad a {
color:#0000ff;text-decoration:none;}
#yiv4282381662 #yiv4282381662ygrp-sponsor
#yiv4282381662ygrp-lc {
font-family:Arial;}

#yiv4282381662 #yiv4282381662ygrp-sponsor
#yiv4282381662ygrp-lc #yiv4282381662hd {
margin:10px
0px;font-weight:700;font-size:78%;line-height:122%;}

#yiv4282381662 #yiv4282381662ygrp-sponsor
#yiv4282381662ygrp-lc .yiv4282381662ad {
margin-bottom:10px;padding:0 0;}

#yiv4282381662 #yiv4282381662actions {
font-family:Verdana;font-size:11px;padding:10px 0;}

#yiv4282381662 #yiv4282381662activity {
background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}

#yiv4282381662 #yiv4282381662activity span {
font-weight:700;}

#yiv4282381662 #yiv4282381662activity span:first-child {
text-transform:uppercase;}

#yiv4282381662 #yiv4282381662activity span a {
color:#5085b6;text-decoration:none;}

#yiv4282381662 #yiv4282381662activity span span {
color:#ff7900;}

#yiv4282381662 #yiv4282381662activity span
.yiv4282381662underline {
text-decoration:underline;}

#yiv4282381662 .yiv4282381662attach {
clear:both;display:table;font-family:Arial;font-size:12px;padding:10px
0;width:400px;}

#yiv4282381662 .yiv4282381662attach div a {
text-decoration:none;}

#yiv4282381662 .yiv4282381662attach img {
border:none;padding-right:5px;}

#yiv4282381662 .yiv4282381662attach label {
display:block;margin-bottom:5px;}

#yiv4282381662 .yiv4282381662attach label a {
text-decoration:none;}

#yiv4282381662 blockquote {
margin:0 0 0 4px;}

#yiv4282381662 .yiv4282381662bold {
font-family:Arial;font-size:13px;font-weight:700;}

#yiv4282381662 .yiv4282381662bold a {
text-decoration:none;}

#yiv4282381662 dd.yiv4282381662last p a {
font-family:Verdana;font-weight:700;}

#yiv4282381662 dd.yiv4282381662last p span {
margin-right:10px;font-family:Verdana;font-weight:700;}

#yiv4282381662 dd.yiv4282381662last p
span.yiv4282381662yshortcuts {
margin-right:0;}

#yiv4282381662 div.yiv4282381662attach-table div div a {
text-decoration:none;}

#yiv4282381662 div.yiv4282381662attach-table {
width:400px;}

#yiv4282381662 div.yiv4282381662file-title a, #yiv4282381662
div.yiv4282381662file-title a:active, #yiv4282381662
div.yiv4282381662file-title a:hover, #yiv4282381662
div.yiv4282381662file-title a:visited {
text-decoration:none;}

#yiv4282381662 div.yiv4282381662photo-title a,
#yiv4282381662 div.yiv4282381662photo-title a:active,
#yiv4282381662 div.yiv4282381662photo-title a:hover,
#yiv4282381662 div.yiv4282381662photo-title a:visited {
text-decoration:none;}

#yiv4282381662 div#yiv4282381662ygrp-mlmsg
#yiv4282381662ygrp-msg p a span.yiv4282381662yshortcuts {
font-family:Verdana;font-size:10px;font-weight:normal;}

#yiv4282381662 .yiv4282381662green {
color:#628c2a;}

#yiv4282381662 .yiv4282381662MsoNormal {
margin:0 0 0 0;}

#yiv4282381662 o {
font-size:0;}

#yiv4282381662 #yiv4282381662photos div {
float:left;width:72px;}

#yiv4282381662 #yiv4282381662photos div div {
border:1px solid
#666666;min-height:62px;overflow:hidden;width:62px;}

#yiv4282381662 #yiv4282381662photos div label {
color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}

#yiv4282381662 #yiv4282381662reco-category {
font-size:77%;}

#yiv4282381662 #yiv4282381662reco-desc {
font-size:77%;}

#yiv4282381662 .yiv4282381662replbq {
margin:4px;}

#yiv4282381662 #yiv4282381662ygrp-actbar div a:first-child {
margin-right:2px;padding-right:5px;}

#yiv4282381662 #yiv4282381662ygrp-mlmsg {
font-size:13px;font-family:Arial, helvetica, clean,
sans-serif;}

#yiv4282381662 #yiv4282381662ygrp-mlmsg table {
font-size:inherit;font:100%;}

#yiv4282381662 #yiv4282381662ygrp-mlmsg select,
#yiv4282381662 input, #yiv4282381662 textarea {
font:99% Arial, Helvetica, clean, sans-serif;}

#yiv4282381662 #yiv4282381662ygrp-mlmsg pre, #yiv4282381662
code {
font:115% monospace;}

#yiv4282381662 #yiv4282381662ygrp-mlmsg * {
line-height:1.22em;}

#yiv4282381662 #yiv4282381662ygrp-mlmsg #yiv4282381662logo {
padding-bottom:10px;}


#yiv4282381662 #yiv4282381662ygrp-msg p a {
font-family:Verdana;}

#yiv4282381662 #yiv4282381662ygrp-msg
p#yiv4282381662attach-count span {
color:#1E66AE;font-weight:700;}

#yiv4282381662 #yiv4282381662ygrp-reco
#yiv4282381662reco-head {
color:#ff7900;font-weight:700;}

#yiv4282381662 #yiv4282381662ygrp-reco {
margin-bottom:20px;padding:0px;}

#yiv4282381662 #yiv4282381662ygrp-sponsor #yiv4282381662ov
li a {
font-size:130%;text-decoration:none;}

#yiv4282381662 #yiv4282381662ygrp-sponsor #yiv4282381662ov
li {
font-size:77%;list-style-type:square;padding:6px 0;}

#yiv4282381662 #yiv4282381662ygrp-sponsor #yiv4282381662ov
ul {
margin:0;padding:0 0 0 8px;}

#yiv4282381662 #yiv4282381662ygrp-text {
font-family:Georgia;}

#yiv4282381662 #yiv4282381662ygrp-text p {
margin:0 0 1em 0;}

#yiv4282381662 #yiv4282381662ygrp-text tt {
font-size:120%;}

#yiv4282381662 #yiv4282381662ygrp-vital ul li:last-child {
border-right:none !important;
}
#yiv4282381662