Homebrew PCBs

I just etched my PS board this morning.  Not too bad for a first try:
http://members.lsol.net/gop4evr/unlinked/psboard.jpg

I used homebrew etchant (2:1 hydrogen peroxide/muriatic acid).  At $2.69/gallon for the muriatic acid and 69 cents/quart for hydrogen peroxide, this sure beats paying $6/pint for the FeCl.  It works well, but has some odor.  I used it outside just as an extra precaution.

Those who were following this project on E101 will notice that I rotated the regs 90 degrees (to make room for the heat sinks and give better airflow).  It was suggested that I add some filled areas for heat dissipation, and I probably went overboard.  I figured that since I had the room to work with, the wider traces couldn't hurt anything and would also give me some fudge room in case of etching voids.  I am pleased with the result, which was made possible by the information I gleaned from this group and related web sites.  Thanks guys.

Nels



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On 10/01/07, DB Express <dbxprss@...> wrote:
>
>
>
>
>
>
> I just etched my PS board this morning.  Not too bad for a first try:
>  http://members.lsol.net/gop4evr/unlinked/psboard.jpg
>
>  I used homebrew etchant (2:1 hydrogen peroxide/muriatic acid).


Can someone explain what this really is?

Such names are meaningless in any other country except the states?

Hydrogen peroxide I think is hair bleach, but if I buy that its
probably got other things in it to spoil it.

What is a muriatic ?

Citric acid is citrus which is orange and lemons, but whats a muriatic
tree look like....

Sorry for giving eveyone a laugh but like I have said before, this is
the UK, we only have maplins and the farm for milk and eggs....

Lez

----- Original Message ----- 

From: Lez
To: Homebrew_PCBs@yahoogroups.com
Sent: Wednesday, January 10, 2007 4:56 PM
Subject: Re: [Homebrew_PCBs] First PCB


On 10/01/07, DB Express <dbxprss@...> wrote:
>
>
>
>
>
>
> I just etched my PS board this morning. Not too bad for a first try:
> http://members.lsol.net/gop4evr/unlinked/psboard.jpg
>
> I used homebrew etchant (2:1 hydrogen peroxide/muriatic acid).

Can someone explain what this really is?

Such names are meaningless in any other country except the states?

Hydrogen peroxide I think is hair bleach, but if I buy that its
probably got other things in it to spoil it.

What is a muriatic ?

Citric acid is citrus which is orange and lemons, but whats a muriatic
tree look like....

Sorry for giving eveyone a laugh but like I have said before, this is
the UK, we only have maplins and the farm for milk and eggs....


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

Hydrogen peroxide is H2O2, used as a bleach by hairdressers. High strength 
H2O2 might be difficult to obtain, suicide bombers often use the stuff to 
make their explosives.

Muriatic acid is the old-fashioned name for hydrochloric acid (HCl). 30% HC1 
is available from hardware stores and building suppliers, it is often used 
for cleaning drains and brickwork.

Leon

----- Original Message ----

From: Lez <lez.briddon@...>>
> I just etched my PS board this morning.  Not too bad for a first try:
>  http://members.lsol.net/gop4evr/unlinked/psboard.jpg
>
>  I used homebrew etchant (2:1 hydrogen peroxide/muriatic acid).


Can someone explain what this really is?


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

(Reading from the bottles)
Muriatic acid:
Hydrogen Chloride -- 31.45% (hydrochloric acid)
Inert ingredients -- 68.55%
This mixture is sold as a farm and industrial solvent/cleaner.  It is used in swmming pools (scary, huh?), and for etching concrete, among many other uses.

Hydrogen peroxide:
"Hydrogen Peroxide Topical Soulution"
"Hydrogen Peroxide (stabilized) 3%"
This is sold here as a solution for cleaning minor cuts and other home medical uses.  I had to use it when I was younger to irrigate an infected ear (not a happy memory).



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[Non-text portions of this message have been removed]

On Wed, 10 Jan 2007 17:56:58 +0100, Lez <lez.briddon@...> wrote:

>
> Can someone explain what this really is?
> Such names are meaningless in any other country except the states?
> Hydrogen peroxide I think is hair bleach, but if I buy that its
> probably got other things in it to spoil it.
> What is a muriatic ?
> Citric acid is citrus which is orange and lemons, but whats a muriatic
> tree look like....
> Sorry for giving eveyone a laugh but like I have said before, this is
> the UK, we only have maplins and the farm for milk and eggs....
> Lez


Muriatic acid is really called hydrochloric acid, HCl, muriatic acid is  
indeed a US thing, and comes in a variety of (mis-)spellings. I do not  
know what "muriatic" comes from either.

Hydrogen peroxide is the correct name for the second chemical though,  
H2O2. Seems just like water, but has more oxygen, which is what we need  
 from it. It is used in "peroxide" bleach. It was used in the "old days" to  
disinfect, similar to iodine (stings too i'm told).


ST

Lez <lez.briddon@...> writes:
> >  I used homebrew etchant (2:1 hydrogen peroxide/muriatic acid).

> Can someone explain what this really is?

Hydrogen Peroxide is H2O2 : http://en.wikipedia.org/wiki/Hydrogen_peroxide

Muriatic acid is HCl in H2O : http://en.wikipedia.org/wiki/Muriatic_acid

> Such names are meaningless in any other country except the states?

Er, they're chemical names.  They should be meaningful in any country.
*Obtaining* them, however, seems to be country-specific, and you have
to get the right strengths (dilutions).

On Wed, 10 Jan 2007 17:50:01 +0100, DB Express <dbxprss@...> wrote:

> I just etched my PS board this morning.  Not too bad for a first try:
> http://members.lsol.net/gop4evr/unlinked/psboard.jpg

Not bad at all! I wish my first try would have had any traces on it ;-)

> I used homebrew etchant (2:1 hydrogen peroxide/muriatic acid).  At  
> $2.69/gallon for the muriatic acid and 69 cents/quart for hydrogen  
> peroxide, this sure beats paying $6/pint for the FeCl.  It works well,  
> but has some odor.  I used it outside just as an extra precaution.

Now you should look into care and feeding of this etchant as CuCl. You can  
use it forever only replenishing small amounts of HCl and regenerating  
with H2O2. You will want to get H2O2 in high concentration (above 20%), or  
you'll add too much water.
How to maintain CuCl can be found in the links section, although many  
guides make it way too complicated.
If your etchant was fuming or bubbling you probably had a much too high  
concentration of one or both of the chemicals. CuCl will not cause any  
smell, or cause any rust to nearby parts, if the concentrations are within  
reason and it is covered when not in use.

> Those who were following this project on E101 will notice that I rotated  
> the regs 90 degrees (to make room for the heat sinks and give better  
> airflow).  It was suggested that I add some filled areas for heat  
> dissipation, and I probably went overboard.  I figured that since I had  
> the room to work with, the wider traces couldn't hurt anything and would  
> also give me some fudge room in case of etching voids.  I am pleased  
> with the result, which was made possible by the information I gleaned  
> from this group and related web sites.  Thanks guys.
> Nels

Also, by using a larger copper area you saved etchant.

ST

Was the H2O2 you used the common over-the-counter drugstore variety (~3%) or the more concentrated (and very dangerous) lab supply kind.

 - jim


On Wed, 10 Jan 2007 08:50:01 -0800 (PST)
DB Express <dbxprss@...> wrote:

> I just etched my PS board this morning.  Not too bad for a first try:
> http://members.lsol.net/gop4evr/unlinked/psboard.jpg
> 
> I used homebrew etchant (2:1 hydrogen peroxide/muriatic acid).  At $2.69/gallon for the muriatic acid and 69 cents/quart for hydrogen peroxide, this sure beats paying $6/pint for the FeCl.  It works well, but has some odor.  I used it outside just as an extra precaution.
> 
> Those who were following this project on E101 will notice that I rotated the regs 90 degrees (to make room for the heat sinks and give better airflow).  It was suggested that I add some filled areas for heat dissipation, and I probably went overboard.  I figured that since I had the room to work with, the wider traces couldn't hurt anything and would also give me some fudge room in case of etching voids.  I am pleased with the result, which was made possible by the information I gleaned from this group and related web sites.  Thanks guys.
> 
> Nels
> 
> 
> 
> __________________________________________________
> Do You Yahoo!?
> Tired of spam?  Yahoo! Mail has the best spam protection around 
> http://mail.yahoo.com 
> 
> [Non-text portions of this message have been removed]
> 
> 
> 
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBs
> 
> If Files or Photos are running short of space, post them here:
> http://groups.yahoo.com/group/Homebrew_PCBs_Archives/ 
> Yahoo! Groups Links
> 
> 
> 
>

----- Original Message ----

From: James Washer <washer@...>

Was the H2O2 you used the common over-the-counter drugstore variety (~3%) or the more concentrated (and very dangerous) lab supply kind.

 - jim


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

3% solution, as sold in drug stores.

Nels



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Hydrogen Peroxide is still used in food processing to disinfect 
packages. For aseptic packaging, milk cartons are first sprayed with 
H2O2 and then heated. The heat decomposes the H2O2 to water and O2 
and the carton is then filled and sealed. This all happens in a 
matter of seconds.

Myc

--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan" 
<stefan_trethan@...> wrote:
>
> On Wed, 10 Jan 2007 17:56:58 +0100, Lez <lez.briddon@...> wrote:
> 
> >
> > Can someone explain what this really is?
> > Such names are meaningless in any other country except the states?
> > Hydrogen peroxide I think is hair bleach, but if I buy that its
> > probably got other things in it to spoil it.
> > What is a muriatic ?
> > Citric acid is citrus which is orange and lemons, but whats a 
muriatic
> > tree look like....
> > Sorry for giving eveyone a laugh but like I have said before, 
this is
> > the UK, we only have maplins and the farm for milk and eggs....
> > Lez
> 
> 
> Muriatic acid is really called hydrochloric acid, HCl, muriatic 
acid is  
> indeed a US thing, and comes in a variety of (mis-)spellings. I do 
not  
> know what "muriatic" comes from either.
> 
> Hydrogen peroxide is the correct name for the second chemical 
though,  
> H2O2. Seems just like water, but has more oxygen, which is what we 
need  
>  from it. It is used in "peroxide" bleach. It was used in the "old 
days" to  

> disinfect, similar to iodine (stings too i'm told).
> 
> 
> ST
>

On Wed, 10 Jan 2007 20:47:02 +0100, mycroft2152 <mycroft2152y@...>  
wrote:

> Hydrogen Peroxide is still used in food processing to disinfect
> packages. For aseptic packaging, milk cartons are first sprayed with
> H2O2 and then heated. The heat decomposes the H2O2 to water and O2
> and the carton is then filled and sealed. This all happens in a
> matter of seconds.
> Myc


I think it's quite useful stuff, since it leaves nothing harmful.
I've seen it recommended for a whole lot of applications, not sure how  
much of that is really working. I tried one time to use it as bleach in  
the washing machine but could not detect any effect.

Seems like a good alternative for those people who have to disinfect  
everything in the house all the time, with H2O2 they would at least do no  
harm. But then there was that story about parents accidentally giving  
their child concentrated H2O2 internally, leading to serious injury. Your  
body was _not_ meant to process H2O2, so don't drink your PCB making  
chemicals ;-).

ST

Hydrochloric acid was first discovered around the year 800 AD by the 
alchemist <http://en.wikipedia.org/wiki/Alchemy_%28islam%29> Jabir ibn 
Hayyan (Geber) <http://en.wikipedia.org/wiki/Geber>, by mixing common 
salt <http://en.wikipedia.org/wiki/Sodium_chloride> with vitriol 
<http://en.wikipedia.org/wiki/Vitriol> (sulfuric acid 
<http://en.wikipedia.org/wiki/Sulfuric_acid>).

In the Middle Ages, hydrochloric acid was known to European alchemists 
as spirit of salt or acidum salis. Gaseous HCl was called marine acid 
air. The old (pre-systematic) name muriatic acid has the same origin 
(muriatic means "pertaining to brine or salt"), and this name is still 
sometimes used.


Roland F.  Harriston
************************************

Lez wrote:

>
>
>
> What is a muriatic ?
>
>

--- In Homebrew_PCBs@yahoogroups.com, DB Express <dbxprss@...> wrote:
>
> I just etched my PS board this morning.  Not too bad for a first try:
> http://members.lsol.net/gop4evr/unlinked/psboard.jpg
> 
> I used homebrew etchant (2:1 hydrogen peroxide/muriatic acid).  At
$2.69/gallon for the muriatic acid and 69 cents/quart for hydrogen
peroxide, this sure beats paying $6/pint for the FeCl.  It works well,
but has some odor.  I used it outside just as an extra precaution.
> 


If I may go off topic on the side of safety and household hazzards.

As you probably found out, the chemicals you used were rather good at
removing metal.  

What you may soon find out, they are SO good, that EVERYTHING metal in
the room in which they are kept will start to rust.  stuff across the
basement and inside of wooden boxes.

I took my Muriatic Acid, sold as such to etch stone and clean
concrete, and I put that into a 5 gallon bucket with a lid that had an
O-ring of silly-cone.

Dave

On Thu, 11 Jan 2007 02:27:14 +0100, Dave Mucha <dave_mucha@...>  
wrote:

>
> If I may go off topic on the side of safety and household hazzards.
> As you probably found out, the chemicals you used were rather good at
> removing metal.
> What you may soon find out, they are SO good, that EVERYTHING metal in
> the room in which they are kept will start to rust.  stuff across the
> basement and inside of wooden boxes.
> I took my Muriatic Acid, sold as such to etch stone and clean
> concrete, and I put that into a 5 gallon bucket with a lid that had an
> O-ring of silly-cone.
> Dave


Plastic bottles seem to be the problem. Although i can not agree about  
"across the basement", something put next to a PE bottle of HCl will rust.  
Also, the bottle will degrade and on the outside you can find some sort of  
salt crystals after some time. I use glass bottles for HCl and H2O2 now.  
(H2O2 will make PE bottles brittle from the inside). Glass seems more  
resistant, but breakage is a danger.

You could also put the HCl inside a second larger container, say a bucket  
with lid. Then it may work to put some chemical in the space between to  
neutralize any acid, maybe NaOH or something. Not sure if the fumes can be  
neutralized this way, but even the two containers should trap most of the  
fumes if you open them outside or something.

You should _never ever_ store any chemicals on a shelf or on the floor or  
something without a second container for safety in case the bottle fails.  
Plastic bottles _will_ fail if given enough time, especially with the aid  
of some chemicals. So put them in a bucket or plastic crate or something.  
(Hint: butchers have great plastic crates that are very sturdy, with two  
handles. I keep the etching tank in such a crate, and the chemical bottles  
behind it in the same crate.)

ST

On 10/01/07, Roland Harriston <rolohar@...> wrote:
>
>
>
>
>
>
> Hydrochloric acid was first discovered around the year 800 AD by the
>  alchemist <http://en.wikipedia.org/wiki/Alchemy_%28islam%29> Jabir ibn
>  Hayyan (Geber) <http://en.wikipedia.org/wiki/Geber>, by mixing common
>  salt <http://en.wikipedia.org/wiki/Sodium_chloride> with vitriol
>  <http://en.wikipedia.org/wiki/Vitriol> (sulfuric acid
>  <http://en.wikipedia.org/wiki/Sulfuric_acid>).
>
>  In the Middle Ages, hydrochloric acid was known to European alchemists
>  as spirit of salt or acidum salis. Gaseous HCl was called marine acid
>  air. The old (pre-systematic) name muriatic acid has the same origin
>  (muriatic means "pertaining to brine or salt"), and this name is still
>  sometimes used

ok, I'l stick to buying FECL at least I can find that stuff.

It took me 2 years to find out what lye was.........


Lez

On Thu, 11 Jan 2007 13:41:44 +0100, Lez <lez.briddon@...> wrote:

> It took me 2 years to find out what lye was.........


Have you heard about google? ;-)

ST

>
> > It took me 2 years to find out what lye was.........
>
>
> Have you heard about google? ;-)

I have now, but had not back then.......

Lez:

If you happen to live in the southwest USA where there are lots
of backyard swimming pools, you can find muriatic acid in
the local supermarkets along with other pool  maintenance
supplies.  Most of the local Ace Hardware stores can get
muriatic acid for you if they don't already have it in stock.
Also, a lot of  construction and building supply emporiums
like Home Depot stock muriatic acid, although they
generally have it large plastic bottles, like one or five gallons.
Ace Hardware stocks it in 1 quart plastic bottles in my area.

And speaking of outgassing and corrosion: Consider the
approximately 1 liter of sulphuric acid that almost everyone
has sitting in the garage most of the time. I'm referring to
the acid in your car battery, and car battery acid is much
stronger (Baume) than domestic Muriatic acid.  And besides
some car batteries are vented!

To date, I have not noticed any of my tools, electronic
test equipment, photolab stuff being attacked by the
gaseous products from batteries in the two cars
residing in my garage, nor have I seen any ill-effects
on the automobiles, paint, wiring, trim,etc.

Personally, I detest Ferric Chloride....nasty stuff.

Roland F. Harriston

**********************
Lez wrote:

>
> On 10/01/07, Roland Harriston <rolohar@... 
> <mailto:rolohar%40comcast.net>> wrote:
> >
> >
> >
> >
> >
> >
> > Hydrochloric acid was first discovered around the year 800 AD by the
> > alchemist <http://en.wikipedia.org/wiki/Alchemy_%28islam%29 
> <http://en.wikipedia.org/wiki/Alchemy_%28islam%29>> Jabir ibn
> > Hayyan (Geber) <http://en.wikipedia.org/wiki/Geber 
> <http://en.wikipedia.org/wiki/Geber>>, by mixing common
> > salt <http://en.wikipedia.org/wiki/Sodium_chloride 
> <http://en.wikipedia.org/wiki/Sodium_chloride>> with vitriol
> > <http://en.wikipedia.org/wiki/Vitriol 
> <http://en.wikipedia.org/wiki/Vitriol>> (sulfuric acid
> > <http://en.wikipedia.org/wiki/Sulfuric_acid 
> <http://en.wikipedia.org/wiki/Sulfuric_acid>>).
> >
> > In the Middle Ages, hydrochloric acid was known to European alchemists
> > as spirit of salt or acidum salis. Gaseous HCl was called marine acid
> > air. The old (pre-systematic) name muriatic acid has the same origin
> > (muriatic means "pertaining to brine or salt"), and this name is still
> > sometimes used
>
> ok, I'l stick to buying FECL at least I can find that stuff.
>
> It took me 2 years to find out what lye was.........
>
> Lez
>
>

>  Personally, I detest Ferric Chloride....nasty stuff.
>
>  Roland F. Harriston

I hate the cost of it if I can use something cheaper etc, never tried
sulphuric acid.......

Lez

Two completely different mineral acids you are talking about.  Hydrochloric 
produces Chlorine gas, and I promise it will corrode things in the vacinity. 
Sulpuric is not as bad about corroding things near it, although take a look 
at the battery tray in an older vehicle for an example of what it can do. 
Neither is particularly dangeraos compared to say Hydrofluric acid; it is 
horrible and very dangerous (etches / dissolves glass, even).

----- Original Message ----- 
From: Roland Harriston
To: Homebrew_PCBs@yahoogroups.com
Sent: Thursday, January 11, 2007 10:27 AM
Subject: Re: [Homebrew_PCBs] "Muriatic Acid" Etymology


Lez:

If you happen to live in the southwest USA where there are lots
of backyard swimming pools, you can find muriatic acid in
the local supermarkets along with other pool maintenance
supplies. Most of the local Ace Hardware stores can get
muriatic acid for you if they don't already have it in stock.
Also, a lot of construction and building supply emporiums
like Home Depot stock muriatic acid, although they
generally have it large plastic bottles, like one or five gallons.
Ace Hardware stocks it in 1 quart plastic bottles in my area.

And speaking of outgassing and corrosion: Consider the
approximately 1 liter of sulphuric acid that almost everyone
has sitting in the garage most of the time. I'm referring to
the acid in your car battery, and car battery acid is much
stronger (Baume) than domestic Muriatic acid. And besides
some car batteries are vented!

To date, I have not noticed any of my tools, electronic
test equipment, photolab stuff being attacked by the
gaseous products from batteries in the two cars
residing in my garage, nor have I seen any ill-effects
on the automobiles, paint, wiring, trim,etc.

Personally, I detest Ferric Chloride....nasty stuff.

Roland F. Harriston

On Thu, 11 Jan 2007 16:27:23 +0100, Roland Harriston <rolohar@...>  
wrote:

>
> And speaking of outgassing and corrosion: Consider the
> approximately 1 liter of sulphuric acid that almost everyone
> has sitting in the garage most of the time. I'm referring to
> the acid in your car battery, and car battery acid is much
> stronger (Baume) than domestic Muriatic acid.  And besides
> some car batteries are vented!
> To date, I have not noticed any of my tools, electronic
> test equipment, photolab stuff being attacked by the
> gaseous products from batteries in the two cars
> residing in my garage, nor have I seen any ill-effects
> on the automobiles, paint, wiring, trim,etc.


You make the assumption here that the two acids would be similar.

Sulphuric acid does not evaporate and form fumes in the same way as  
hydrochloric acid.

I don't pretend to understand all those complicated things like vapor  
pressure, but maybe someone else is qualified to elaborate.
Look at the boiling points though, over 300C for sulphuric acid and  
something like 50 or 60C for HCl. That'll tell you something about how  
well is evaporating at room temperature.

I can confirm from first hand experience, not assumption, that HCl will  
cause stuff to rust, if left open, in a significant area. Even a closed  
plastic bottle made a spray can rust which was inches away.

ST

>
> Two completely different mineral acids you are talking about.  Hydrochloric
>  produces Chlorine gas, and I promise it will corrode things in the vacinity.
>  Sulpuric is not as bad about corroding things near it, although take a look
>  at the battery tray in an older vehicle for an example of what it can do.
>  Neither is particularly dangeraos compared to say Hydrofluric acid; it is
>  horrible and very dangerous (etches / dissolves glass, even).

But can battery acid be used as an etchant?
Lez

I do not think so, but the experts in here will know.  They are talking about Hydrochloric acid mixed with hydrogen peroxide, not Sulfuric acid as far as I know.

Incidentally, drug store concentration peroxide is safe to handle, but the lab grade concentrated stuff is quite dangerous.  It has so much oxygen available, that a spec of dust falling in the bottle of highly concentrated hydrogen peroxide can cause a violent reaction.

Also, I think you will find "Muriatic" is an old world term, and should be commonly understood there in the UK as well as here in the New World.  Masons have used it since antiquity and it is used in many other trades.

  ----- Original Message ----- 
  From: Lez 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Thursday, January 11, 2007 12:15 PM
  Subject: Re: [Homebrew_PCBs] "Muriatic Acid" Etymology


  >
  > Two completely different mineral acids you are talking about. Hydrochloric
  > produces Chlorine gas, and I promise it will corrode things in the vacinity.
  > Sulpuric is not as bad about corroding things near it, although take a look
  > at the battery tray in an older vehicle for an example of what it can do.
  > Neither is particularly dangeraos compared to say Hydrofluric acid; it is
  > horrible and very dangerous (etches / dissolves glass, even).

  But can battery acid be used as an etchant?
  Lez


   

[Non-text portions of this message have been removed]

On Thu, 11 Jan 2007 18:15:09 +0100, Lez <lez.briddon@...> wrote:

> But can battery acid be used as an etchant?
> Lez


Sulphuric acid can be used in combination with H2O2 regeneration in a  
copper sulphate producing process similar to CuCl. There was some good  
reason why CuCl is better for homebrew use, but i can't remember it now.

ST

In article <005101c735a7$5c6c7210$0100a8c0@House>,
   "AnaLog Services, Inc." <wireline@...> wrote:
> Also, I think you will find "Muriatic" is an old world term,

"Historic" term is the word, everyone I know would refer to it as
"Hydrochloric"

Analog:

I have had muriatic acid in plastic containers in my garage
for a while now, and have not noticed that it has affected
anything in the garage, including the items previously
mentioned. In this neck of the woods, I don't think it is unusual for
folks to have muriatic acid and other pool maintenance
chemicals around the house most of the time, and nearly
all of this time the materials are in the containers they
were purchased in.

I don't know about having the peroxide/muriatic acid mixture
setting around the house, because I usually neutralize the batch
I have just used with sodium bicarbonate, and get rid of it.
The stuff is cheap enough to allow me to do this.

Since the southern Arizona desert is a very arid environment,
we don't have the relative humidity that might cause problems
in other portions of the world.

And, it is not unusual for the temperature to go up to 90 degrees F (or 
higher)
in my garage during the summer months.

In the supermarkets around here, I see a large number of 4-pack
cartons of muriatic acid, each containing 4,  1gallon jugs.
I have never seen or heard of any ill-effects on anything else in the 
supermarket
as a result of being around that much muriatic acid 24 hours, 7 days a week,
356 days a year.  At the local Home Depot, the 5 gallon jugs of muriatic
are stored outside in the garden supply area, but I think this is simply
because all the other pool maintenance stuff is out there.  At Ace
Hardware, 1 qt and 1 gal jugs are on the shelves inside the store.

This leads me to believe that it is the strength of the substance (Baume)
that makes the difference.

I'll close my contribution to this discussion by stating that my personal
experience has shown that the peroxide/muriatic acid etchant is
both effective and economical.  In addition, it leaves no ugly brown
stains.

The most important part is that my wife has informed that she will pay for
all the peroxide and muriatic acid I can possibly use.....if I just 
don't bring
that "brown stuff" anywhere near the house anymore!

That means I can integrate some of my hobby expenses into the weekly
grocery bill.

Roland F. Harriston

***************************************
AnaLog Services, Inc. wrote:

>
> Two completely different mineral acids you are talking about. 
> Hydrochloric
> produces Chlorine gas, and I promise it will corrode things in the 
> vacinity.
> Sulpuric is not as bad about corroding things near it, although take a 
> look
> at the battery tray in an older vehicle for an example of what it can do.
> Neither is particularly dangeraos compared to say Hydrofluric acid; it is
> horrible and very dangerous (etches / dissolves glass, even).
>
> ----- Original Message -----
> From: Roland Harriston
> To: Homebrew_PCBs@yahoogroups.com <mailto:Homebrew_PCBs%40yahoogroups.com>
> Sent: Thursday, January 11, 2007 10:27 AM
> Subject: Re: [Homebrew_PCBs] "Muriatic Acid" Etymology
>
> Lez:
>
> If you happen to live in the southwest USA where there are lots
> of backyard swimming pools, you can find muriatic acid in
> the local supermarkets along with other pool maintenance
> supplies. Most of the local Ace Hardware stores can get
> muriatic acid for you if they don't already have it in stock.
> Also, a lot of construction and building supply emporiums
> like Home Depot stock muriatic acid, although they
> generally have it large plastic bottles, like one or five gallons.
> Ace Hardware stocks it in 1 quart plastic bottles in my area.
>
> And speaking of outgassing and corrosion: Consider the
> approximately 1 liter of sulphuric acid that almost everyone
> has sitting in the garage most of the time. I'm referring to
> the acid in your car battery, and car battery acid is much
> stronger (Baume) than domestic Muriatic acid. And besides
> some car batteries are vented!
>
> To date, I have not noticed any of my tools, electronic
> test equipment, photolab stuff being attacked by the
> gaseous products from batteries in the two cars
> residing in my garage, nor have I seen any ill-effects
> on the automobiles, paint, wiring, trim,etc.
>
> Personally, I detest Ferric Chloride....nasty stuff.
>
> Roland F. Harriston
>
>

I would not expect you to have much trouble with it in sealed containers.  And certainly your low humidity is a factor (the gas goes back into solution in the water vapor in high humidity environments and is responsible for much of the corrosion seen).  Nevertheless, even out there where it is dry, if you leave open containers of the stuff laying around, you will see nasty effects.

  ----- Original Message ----- 
  From: Roland Harriston 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Thursday, January 11, 2007 2:37 PM
  Subject: Re: [Homebrew_PCBs] "Muriatic Acid": Corrosion, Etc.


  Analog:

  I have had muriatic acid in plastic containers in my garage
  for a while now, and have not noticed that it has affected
  anything in the garage, including the items previously
  mentioned. In this neck of the woods, I don't think it is unusual for
  folks to have muriatic acid and other pool maintenance
  chemicals around the house most of the time, and nearly
  all of this time the materials are in the containers they
  were purchased in.

  I don't know about having the peroxide/muriatic acid mixture
  setting around the house, because I usually neutralize the batch
  I have just used with sodium bicarbonate, and get rid of it.
  The stuff is cheap enough to allow me to do this.

  Since the southern Arizona desert is a very arid environment,
  we don't have the relative humidity that might cause problems
  in other portions of the world.

  And, it is not unusual for the temperature to go up to 90 degrees F (or 
  higher)
  in my garage during the summer months.

  In the supermarkets around here, I see a large number of 4-pack
  cartons of muriatic acid, each containing 4, 1gallon jugs.
  I have never seen or heard of any ill-effects on anything else in the 
  supermarket
  as a result of being around that much muriatic acid 24 hours, 7 days a week,
  356 days a year. At the local Home Depot, the 5 gallon jugs of muriatic
  are stored outside in the garden supply area, but I think this is simply
  because all the other pool maintenance stuff is out there. At Ace
  Hardware, 1 qt and 1 gal jugs are on the shelves inside the store.

  This leads me to believe that it is the strength of the substance (Baume)
  that makes the difference.

  I'll close my contribution to this discussion by stating that my personal
  experience has shown that the peroxide/muriatic acid etchant is
  both effective and economical. In addition, it leaves no ugly brown
  stains.

  The most important part is that my wife has informed that she will pay for
  all the peroxide and muriatic acid I can possibly use.....if I just 
  don't bring
  that "brown stuff" anywhere near the house anymore!

  That means I can integrate some of my hobby expenses into the weekly
  grocery bill.

  Roland F. Harriston

  ***************************************
  AnaLog Services, Inc. wrote:
  >
  > Two completely different mineral acids you are talking about. 
  > Hydrochloric
  > produces Chlorine gas, and I promise it will corrode things in the 
  > vacinity.
  > Sulpuric is not as bad about corroding things near it, although take a 
  > look
  > at the battery tray in an older vehicle for an example of what it can do.
  > Neither is particularly dangeraos compared to say Hydrofluric acid; it is
  > horrible and very dangerous (etches / dissolves glass, even).
  >
  > ----- Original Message -----
  > From: Roland Harriston
  > To: Homebrew_PCBs@yahoogroups.com <mailto:Homebrew_PCBs%40yahoogroups.com>
  > Sent: Thursday, January 11, 2007 10:27 AM
  > Subject: Re: [Homebrew_PCBs] "Muriatic Acid" Etymology
  >
  > Lez:
  >
  > If you happen to live in the southwest USA where there are lots
  > of backyard swimming pools, you can find muriatic acid in
  > the local supermarkets along with other pool maintenance
  > supplies. Most of the local Ace Hardware stores can get
  > muriatic acid for you if they don't already have it in stock.
  > Also, a lot of construction and building supply emporiums
  > like Home Depot stock muriatic acid, although they
  > generally have it large plastic bottles, like one or five gallons.
  > Ace Hardware stocks it in 1 quart plastic bottles in my area.
  >
  > And speaking of outgassing and corrosion: Consider the
  > approximately 1 liter of sulphuric acid that almost everyone
  > has sitting in the garage most of the time. I'm referring to
  > the acid in your car battery, and car battery acid is much
  > stronger (Baume) than domestic Muriatic acid. And besides
  > some car batteries are vented!
  >
  > To date, I have not noticed any of my tools, electronic
  > test equipment, photolab stuff being attacked by the
  > gaseous products from batteries in the two cars
  > residing in my garage, nor have I seen any ill-effects
  > on the automobiles, paint, wiring, trim,etc.
  >
  > Personally, I detest Ferric Chloride....nasty stuff.
  >
  > Roland F. Harriston
  >
  > 


   

[Non-text portions of this message have been removed]

Analog:

I fully agree that having open containers of almost _anything
_is a bad idea!

That's why I always finish off a bottle of vodka
as quickly as possible, once the seal has been broken!

Roland F. Harriston
*************************
AnaLog Services, Inc. wrote:

>
> I would not expect you to have much trouble with it in sealed 
> containers. And certainly your low humidity is a factor (the gas goes 
> back into solution in the water vapor in high humidity environments 
> and is responsible for much of the corrosion seen). Nevertheless, even 
> out there where it is dry, if you leave open containers of the stuff 
> laying around, you will see nasty effects.
>
>
> ,___

It is indeed an historic name, but it is still in common use.

  ----- Original Message ----- 
  From: lists 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Thursday, January 11, 2007 2:12 PM
  Subject: Re: [Homebrew_PCBs] "Muriatic Acid" Etymology


  In article <005101c735a7$5c6c7210$0100a8c0@House>,
  "AnaLog Services, Inc." <wireline@...> wrote:
  > Also, I think you will find "Muriatic" is an old world term,

  "Historic" term is the word, everyone I know would refer to it as
  "Hydrochloric"



   

[Non-text portions of this message have been removed]

In article <xnsleizsdf.fsf@...>,
   DJ Delorie <dj@...> wrote:
> Muriatic acid is HCl in H2O : http://en.wikipedia.org/wiki/Muriatic_acid

> > Such names are meaningless in any other country except the states?

> Er, they're chemical names.  They should be meaningful in any country.
> *Obtaining* them, however, seems to be country-specific, and you have
> to get the right strengths (dilutions).

Muriatic is NOT a standard chemical name. Someone from the 19th century
would be familiar with it but not anymore. I have a very old chemistry
text book from around 1870 in which such names are common place but it
would be found in no chemical text book printed after WWII

--- In Homebrew_PCBs@yahoogroups.com, lists <stuart.winsor.lists@...>
wrote:
>
> In article <xnsleizsdf.fsf@...>,
>    DJ Delorie <dj@...> wrote:
> > Muriatic acid is HCl in H2O :
http://en.wikipedia.org/wiki/Muriatic_acid
> 
> > > Such names are meaningless in any other country except the states?
> 
> > Er, they're chemical names.  They should be meaningful in any country.
> > *Obtaining* them, however, seems to be country-specific, and you have
> > to get the right strengths (dilutions).
> 
> Muriatic is NOT a standard chemical name. Someone from the 19th century
> would be familiar with it but not anymore. 

It may be an old term, but you can find it in almost any hardware
store with the label of Muriatic acid.

Lowes has it on their web site, and every contractor I have ever
spoken to about etching or cleaning concrete offers Muriatic Acid
before anything else.

It's roots are old, but it's name is well known.

But, I suspect it is staying around because of the old timers.  the
kids will probably know it by both and at some point, it will be
somethin us old farts reminiss about.

Dave

> > Muriatic is NOT a standard chemical name. Someone from the 19th century
> > would be familiar with it but not anymore. 
> 
> It may be an old term, but you can find it in almost any hardware
> store with the label of Muriatic acid.

If I walk into a store and ask for "Hydrocloric" acid, all what I will get is a
dumb look. If I ask for "Muriatic" then even the cashier will point to the
right shelf!
Ever heard about "lye" or "baking soda"? Are they chemical names?


 
____________________________________________________________________________________
Do you Yahoo!?
Everyone is raving about the all-new Yahoo! Mail beta.
http://new.mail.yahoo.com

Just for fun, I checked Google, and got 257,000 hits for Muriatic acid, so somebody is still familiar with the term!  It was certainly mentioned in my high school chemistry text as a common name for Hydrochloric acid, but that was admittedly a few years back.  There is nothing wrong with the common or generic names for chemicals.  You are simply wrong that Muriatic acid is an obsolete or improper term.  For purposes of clarity, Hydrochloric acid is the better technical term, but demanding the use of the proper technical term would be like demanding folks stop calling ASA aspirin, since aspirin is a very old common name and not the correct technical chemical name.

  ----- Original Message ----- 
  From: lists 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Thursday, January 11, 2007 5:45 PM
  Subject: Re: [Homebrew_PCBs] First PCB


  In article <xnsleizsdf.fsf@...>,
  DJ Delorie <dj@...> wrote:
  > Muriatic acid is HCl in H2O : http://en.wikipedia.org/wiki/Muriatic_acid

  > > Such names are meaningless in any other country except the states?

  > Er, they're chemical names. They should be meaningful in any country.
  > *Obtaining* them, however, seems to be country-specific, and you have
  > to get the right strengths (dilutions).

  Muriatic is NOT a standard chemical name. Someone from the 19th century
  would be familiar with it but not anymore. I have a very old chemistry
  text book from around 1870 in which such names are common place but it
  would be found in no chemical text book printed after WWII



   

[Non-text portions of this message have been removed]

----- Original Message ----- 

From: AnaLog Services, Inc.
To: Homebrew_PCBs@yahoogroups.com
Sent: Friday, January 12, 2007 4:52 AM
Subject: Re: [Homebrew_PCBs] First PCB


Just for fun, I checked Google, and got 257,000 hits for Muriatic acid, so 
somebody is still familiar with the term! It was certainly mentioned in my 
high school chemistry text as a common name for Hydrochloric acid, but that 
was admittedly a few years back. There is nothing wrong with the common or 
generic names for chemicals. You are simply wrong that Muriatic acid is an 
obsolete or improper term. For purposes of clarity, Hydrochloric acid is the 
better technical term, but demanding the use of the proper technical term 
would be like demanding folks stop calling ASA aspirin, since aspirin is a 
very old common name and not the correct technical chemical name.

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

"Spirits of salts" is what it is often called here in the UK. That is a very 
old name.

Leon
--
Leon Heller
Amateur radio call-sign G1HSM
Yaesu FT-817ND transceiver
Suzuki SV1000S motorcycle
leon355@...
http://www.geocities.com/leon_heller

On Thu, 11 Jan 2007 23:45:02 +0100, lists  
<stuart.winsor.lists@...> wrote:

>
> Muriatic is NOT a standard chemical name. Someone from the 19th century
> would be familiar with it but not anymore. I have a very old chemistry
> text book from around 1870 in which such names are common place but it
> would be found in no chemical text book printed after WWII


Give it up, it's a US thing. They like them old obsolete terms, same with  
yards, inches, feet and the like.
You'll never talk sense into them, it's a matter of pride.

ST

> Give it up, it's a US thing. They like them old obsolete terms, same with
> yards, inches, feet and the like.
> You'll never talk sense into them, it's a matter of pride.
>
> ST

Well as being British we invented the roots of there language, now
there trying to teach it us with their colorful ways.........

But I think your right about the terms, they wont change, like the
American mindset, no retreat, no surrender.............

As for using google to prove the popularity of a word, as its hitting
about 80% of american sites and 20% of them are from the rest of the
world, no wonder the American spellings have higher hits.

>  Also, I think you will find "Muriatic" is an old world term, and should be commonly understood there in the UK as well as here in the New World.  Masons have used it since antiquity and it is used in many other trades.
>

Yes maybe, but it wont be on sale as that in the uk, even under a
different name, we DONT sell chemicals over the counter in the UK,
they have to ordered, with all the paperwork, from checmical supply
companies.

So, the only way in the UK to get something is to hope that it has a
legitimate use for sale, IE lye for cleaning drains, although very
rare is lye sold in the uk, or that it is used in sufficient
concentration in another kitchen product etc that it can be used as is
or refined.

This is all to do with bombs etc and general public safety, if its
harmful, we dont sell it, I cant imagine the amount of problems the
last bombers had to get anything..........



Lez

> > Give it up, it's a US thing. They like them old obsolete 
> terms, same 
> > with yards, inches, feet and the like.
> > You'll never talk sense into them, it's a matter of pride.
> >
> > ST
> 
> Well as being British we invented the roots of there 
> language, now there trying to teach it us with their colorful 
> ways.........
> 
> But I think your right about the terms, they wont change, 
> like the American mindset, no retreat, no surrender.............
> 
> As for using google to prove the popularity of a word, as its 
> hitting about 80% of american sites and 20% of them are from 
> the rest of the world, no wonder the American spellings have 
> higher hits.


NASA has gone metric, hooray say those who probes are splattered over Mars.
Well, some of them.

I did have a chuckle at an American 'lifestyle' program the other day.  A
bunch of builders/contractors were trying to make some wooden arches, which
involved a bit of maths.  Much muttering & grumbling about fractions was
heard, the end result being they got it wrong anyway.  I guess they couldn't
afford the fancy nerd calculators.  Or just go metric and do all your
measuring in millimeters, it's easier than you think.

Pay closer attention to Google, it kind of treats different spellings as the
same, but the results are not quite that you think.  Compare color & colour.

Tony

On Fri, 12 Jan 2007 14:46:32 +0100, Lez <lez.briddon@...> wrote:

>
> This is all to do with bombs etc and general public safety, if its
> harmful, we dont sell it, I cant imagine the amount of problems the
> last bombers had to get anything..........


Probably very little.
"problems" is a relative term, and become rather small if you are planning  
to blow yourself up ;-)

<http://news.bbc.co.uk/1/hi/programmes/kenyon_confronts/3149502.stm>

H2O2 is sold as pool chemical (for oxygen based systems), usually as 25%  
under different brand names. HCl should be available as pool chemical too,  
although here it is only used for public pools, private ones use a dry  
substance instead.

I would still suggest trying to jump through all the hoops in order to buy  
chemicals for your legitimate use, just to spite them if nothing else.  
Also, if you want to buy chamicals, you need to find specialist chemicals  
shops, not pharmacies, or DIY stores, or anything.

ST

Offensive nonsense.

  ----- Original Message ----- 
  From: Lez 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Friday, January 12, 2007 8:02 AM
  Subject: Re: [Homebrew_PCBs] First PCB


  > Give it up, it's a US thing. They like them old obsolete terms, same with
  > yards, inches, feet and the like.
  > You'll never talk sense into them, it's a matter of pride.
  >
  > ST

  Well as being British we invented the roots of there language, now
  there trying to teach it us with their colorful ways.........

  But I think your right about the terms, they wont change, like the
  American mindset, no retreat, no surrender.............

  As for using google to prove the popularity of a word, as its hitting
  about 80% of american sites and 20% of them are from the rest of the
  world, no wonder the American spellings have higher hits.


   

[Non-text portions of this message have been removed]

> H2O2 is sold as pool chemical (for oxygen based systems), usually as 25%
> under different brand names. HCl should be available as pool chemical too,
> although here it is only used for public pools, private ones use a dry
> substance instead.

In the city of york I know 0 ppl with pools, in the village I grew up
in, 0, in my brother in laws town, 0....................

Our BEST kitchen / household chemical suppliers are...........

http://www.maplin.co.uk/

http://www.asda.co.uk/

http://www.boots.co.uk/

they sell things like kitchen worktop cleaner, products based on 'citrus power'

Doing a search I have found it de-scales ? is this right ? if so maybe
its used in de-scaling products designed to be dropped into the toilet
bowl and left overnight...........
box says 5%(oxygen based bleaching agent, anionic surfactants,
polycarboxylates), 95%other ingrediants

I have however found this..........
https://www.helios.co.uk/cgi-bin/store.cgi?action=link&sku=Muri-ac&uid=1762

QED.

> -----Original Message-----
> From: Homebrew_PCBs@yahoogroups.com 
> [mailto:Homebrew_PCBs@yahoogroups.com] On Behalf Of AnaLog 
> Services, Inc.
> Sent: Saturday, 13 January 2007 2:31 AM
> To: Homebrew_PCBs@yahoogroups.com
> Subject: Re: [Homebrew_PCBs] First PCB
> 
> Offensive nonsense.
> 
>   ----- Original Message -----
>   From: Lez
>   To: Homebrew_PCBs@yahoogroups.com
>   Sent: Friday, January 12, 2007 8:02 AM
>   Subject: Re: [Homebrew_PCBs] First PCB
> 
> 
>   > Give it up, it's a US thing. They like them old obsolete 
> terms, same with
>   > yards, inches, feet and the like.
>   > You'll never talk sense into them, it's a matter of pride.
>   >
>   > ST
> 
>   Well as being British we invented the roots of there language, now
>   there trying to teach it us with their colorful ways.........
> 
>   But I think your right about the terms, they wont change, like the
>   American mindset, no retreat, no surrender.............
> 
>   As for using google to prove the popularity of a word, as 
> its hitting
>   about 80% of american sites and 20% of them are from the rest of the
>   world, no wonder the American spellings have higher hits.
> 
> 
>    
> 
> [Non-text portions of this message have been removed]
> 
> 
> 
> Be sure to visit the group home and check for new Links, 
> Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBs
> 
> If Files or Photos are running short of space, post them here:
> http://groups.yahoo.com/group/Homebrew_PCBs_Archives/
> Yahoo! Groups Links
> 
> 
> 
>

On Fri, 12 Jan 2007 16:58:39 +0100, Lez <lez.briddon@...> wrote:

> In the city of york I know 0 ppl with pools, in the village I grew up
> in, 0, in my brother in laws town, 0....................
> Our BEST kitchen / household chemical suppliers are...........
> http://www.maplin.co.uk/
> http://www.asda.co.uk/
> http://www.boots.co.uk/
> they sell things like kitchen worktop cleaner, products based on 'citrus  
> power'
> Doing a search I have found it de-scales ? is this right ? if so maybe
> its used in de-scaling products designed to be dropped into the toilet
> bowl and left overnight...........
> box says 5%(oxygen based bleaching agent, anionic surfactants,
> polycarboxylates), 95%other ingrediants
> I have however found this..........
> https://www.helios.co.uk/cgi-bin/store.cgi?action=link&sku=Muri-ac&uid=1762


How about <http://www.scichem.com/>?

De-scalers could contain HCl (that would work well), but could also be  
beased on something else that will not corrode metals.

ST

Well as being British we invented the roots of there (their) language, now
there (they are) trying to teach it us with their colorful (colourful) ways.........

But (grammar; starting a sentence with 'But') I think your right about the terms, they wont (won't, as in will not?) change, like the American mindset, no retreat, no surrender.............


Being British myself, I find it offensive when someone from my country criticises the colonials in their use of English, when they patently cannot use it themselves. See corrections above.

What has this to do with printed circuit board making?

Regards,

Terry



Offensive nonsense.

  ----- Original Message ----- 
  From: Lez 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Friday, January 12, 2007 8:02 AM
  Subject: Re: [Homebrew_PCBs] First PCB


  > Give it up, it's a US thing. They like them old obsolete terms, same with
  > yards, inches, feet and the like.
  > You'll never talk sense into them, it's a matter of pride.
  >
  > ST

  Well as being British we invented the roots of there language, now
  there trying to teach it us with their colorful ways.........

  But I think your right about the terms, they wont change, like the
  American mindset, no retreat, no surrender.............

  As for using google to prove the popularity of a word, as its hitting
  about 80% of american sites and 20% of them are from the rest of the
  world, no wonder the American spellings have higher hits.


   

[Non-text portions of this message have been removed]



Be sure to visit the group home and check for new Links, Files, and Photos:
http://groups.yahoo.com/group/Homebrew_PCBs

If Files or Photos are running short of space, post them here:
http://groups.yahoo.com/group/Homebrew_PCBs_Archives/ 
Yahoo! Groups Links






[Non-text portions of this message have been removed]

>   Well as being British we invented the roots of there language, now
>   there trying to teach it us with their colorful ways.........
>
>   But I think your right about the terms, they wont change, like the
>   American mindset, no retreat, no surrender.............
>
>   As for using google to prove the popularity of a word, as its hitting
>   about 80% of american sites and 20% of them are from the rest of the
>   world, no wonder the American spellings have higher hits.

Remarkable. It seems even among the British there are many who don't know
the difference between there, their and they're. Not to mention the correct
use of apostrophe, capitalization and punctuation. Not that Americans are
any better. Probably a result of public school emphasis on diversity at the
expense of education.
--
Phil Mattison
http://www.ohmikron.com/
Motors::Drivers::Controllers::Software

> 
> You could also put the HCl inside a second larger container, say a
bucket  
> with lid. 

This is what I did.  I used the origional plastic bottle. figuring the
supplier/packager put the Muriatic acid in a suitable container.

I then placed that container inside of a 5 gallon bucket with a lid. 
the bucket is an old paint bucket.

What I did not do, and should, is to full the lower space with kitty
letter to absorb any spills.

I did notice the white crystals that, I assume were from fumes
adsorbing near the cap.  I also noticed that things within about 3
meters had rust on them, and raw pc boards that were about 6 meters
away had started to oxidize.  

Once I incapsulated the origional plastic bottle, there have not been
any further rusting or oxidation episodes.

Secondary containent is a good idea, and a method of absorbing any
spills is an excelent one.

Dave

ps: Phil, life is two short to worry about how words are used on
they're side of the pond.  I to do have to think about how there words
are used when I translate from over their to over here.  your better
off being more forgiving on posts as some day, you're posts will be
pulled apart as someone will think they have too point your you're errors.

http://www.better-english.com/easier/theyre.htm

And, yes, there is not one 'to' or 'there' in that paragraph is that
is in the correct place.  If you're too senstive, their posts will
driver you from here to there and back.

Dave

On Fri, 12 Jan 2007 20:11:43 +0100, Dave Mucha <dave_mucha@...>  
wrote:

> This is what I did.  I used the origional plastic bottle. figuring the
> supplier/packager put the Muriatic acid in a suitable container.
> I then placed that container inside of a 5 gallon bucket with a lid.
> the bucket is an old paint bucket.
> What I did not do, and should, is to full the lower space with kitty
> letter to absorb any spills.

I'm not so sure now that's actually a good idea. In case of a spill a  
violent chemical reaction would take place, probably releasing gasses that  
might put the bucket under pressure or heat causing all sorts of trouble.  
Also, "pure" HCl seems easier to re-use or neutralize for disposal than  
some mixtures you might get.


ST

In article <c3241b80701120758u5bc2632ob28aa41e44c5dcc0@...>,
   Lez <lez.briddon@...> wrote:
> I have however found this..........
> https://www.helios.co.uk/cgi-bin/store.cgi?action=link&sku=Muri-ac&uid=1762

Hmmmm, seems a bit strange. However, a little while ago I came across:

http://www.labpakchemicals.com/

I was deterred by the £50 minimum order but maybe us UK members could get
together to make up a £50 order and then split it between us.

Note that 1 litre 36% HCl is £5.99 and 2litre 100Vol H2O2 is £8.29

Stuart

Terry Owens(jo001k1132@...) is reported to have said:
> Well as being British we invented the roots of there (their) language, now
> there (they are) trying to teach it us with their colorful (colourful) ways.........
> 
> But (grammar; starting a sentence with 'But') I think your right about the terms, they wont (won't, as in will not?) change, like the American mindset, no retreat, no surrender.............
> 
> 
> Being British myself, I find it offensive when someone from my country criticises the colonials in their use of English, when they patently cannot use it themselves. See corrections above.
> 

Thanks for that Terry.  We let is slide, as we knew he was english.

WT

> Give it up, it's a US thing. They like them old obsolete terms, same with  
> yards, inches, feet and the like.
> You'll never talk sense into them, it's a matter of pride.

BTW, do you know what the standard (definition) for an inch is?
believe it or not: it's 0.0254 meter! so, at last, the US 'IS' metric, although
a very crazy one... go figure!



 
____________________________________________________________________________________
Want to start your own business?
Learn how on Yahoo! Small Business.
http://smallbusiness.yahoo.com/r-index

--- Lez <lez.briddon@...> wrote:
> 
> This is all to do with bombs etc and general public safety, if its
> harmful, we dont sell it, I cant imagine the amount of problems the
> last bombers had to get anything..........

I guess the bombers had little or no problem getting what they needed, these
laws are targeted towards the general public not for specifics, it's a matter
of 'public relations'.
We had similar ambient during our 'socialist' epoch.
If you really need to prohibit all danger, cut off the water supply... just too
many people have drowned!


 
____________________________________________________________________________________
Now that's room service!  Choose from over 150,000 hotels
in 45,000 destinations on Yahoo! Travel to find your fit.
http://farechase.yahoo.com/promo-generic-14795097

On 12/01/07, Wayne Topa <linuxone@...> wrote:
>
>
>
>
>
>
> Terry Owens(jo001k1132@...) is reported to have said:
>  > Well as being British we invented the roots of there (their) language, now
>  > there (they are) trying to teach it us with their colorful (colourful) ways.........
>  >
>  > But (grammar; starting a sentence with 'But') I think your right about the terms, they wont (won't, as in will not?) change, like the American mindset, no retreat, no surrender.............
>  >
>  >
>  > Being British myself, I find it offensive when someone from my country criticises the colonials in their use of English, when they patently cannot use it themselves. See corrections above.
>  >
>
>  Thanks for that Terry.  We let is slide, as we knew he was english.


Well what do you expect after over 10 years of having to converse in
Anglish.......

I make no point of saying I'm the keeper of the ring of pure grammer,
having little education in things like 'history' and 'english' and any
other subject that was not scientific, I opted out of those to do
physics, woodwork and metal work, then left school early to work in
an, ooh what do you call them, 'autoshop' ? -  a place were people
bring their cars to be repaired?

I dont want to have offended anybody what I wrote was tongue in cheek,
if that translates I dont know. over their you may do something
different, finger in ear or something.



Lez

----- Original Message ----- 

From: lists
To: Homebrew_PCBs@yahoogroups.com
Sent: Friday, January 12, 2007 9:01 PM
Subject: Re: [Homebrew_PCBs] "Muriatic Acid" Etymology


In article <c3241b80701120758u5bc2632ob28aa41e44c5dcc0@...>,
Lez <lez.briddon@...> wrote:
> I have however found this..........
> https://www.helios.co.uk/cgi-bin/store.cgi?action=link&sku=Muri-ac&uid=1762

Hmmmm, seems a bit strange. However, a little while ago I came across:

http://www.labpakchemicals.com/

I was deterred by the \ufffd50 minimum order but maybe us UK members could get
together to make up a \ufffd50 order and then split it between us.

Note that 1 litre 36% HCl is \ufffd5.99 and 2litre 100Vol H2O2 is \ufffd8.29

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

I'd be interested.

Leon
--
Leon Heller
Amateur radio call-sign  G1HSM
Yaesu FT-817ND transceiver
Suzuki SV1000S motorcycle
leon355@...
http://www.geocities.com/leon_heller

On Fri, 12 Jan 2007 22:01:02 +0100, lists  
<stuart.winsor.lists@...> wrote:

> Hmmmm, seems a bit strange. However, a little while ago I came across:
> http://www.labpakchemicals.com/
> I was deterred by the \ufffd50 minimum order but maybe us UK members could get
> together to make up a \ufffd50 order and then split it between us.
> Note that 1 litre 36% HCl is \ufffd5.99 and 2litre 100Vol H2O2 is \ufffd8.29
> Stuart


Even so, seems quite expensive. If you really only need H2O2 and HCl i  
suspect the pool chemicals route may be the way to go after all. I suggest  
going to your local _public_ pool and asking them for their supplier. HCl  
should be found that way.
If the pool chemicals supplier does not have H2O2 as well, try a  
hairdressers supply. Although they usually use gel H2O2 these days, i have  
seen liquid one for sale there and also above 20% concentration.

ST

On 12 Jan 2007, at 17:46, Terry Owens wrote:

> But (grammar; starting a sentence with 'But')

Used in the right circumstances it is OK.

> Being British myself, I find it offensive when someone from my  
> country criticises the colonials in their use of English, when they  
> patently cannot use it themselves. See corrections above.

It gets harder and harder to spell and punctuate when there are so  
many mistakes made - even leaving aside the country differences.

> What has this to do with printed circuit board making?

Quite a lot really. Can change the meaning of a sentence.

-- 

Cheers

Derryck

On Sat, 13 Jan 2007 11:20:14 +0100, Leon <leon355@...> wrote:

>
> I'd be interested.
> Leon


Is it tricky in the UK to send chemicals via mail? I mean one could argue  
they didn't have to know, but still, i think not all postal services allow  
strong acids and stuff.

I'd still suggest spending some time on the phone, or visiting relevant  
places. Even if they can't help you they'll send you somewhere else where  
they may have what you want. For example if you call a bulk distributor  
they'll usually be able to tell you where you can buy small quantities,  
because those shops are their customers, and you can be sure they got  
requests just like yours many times before.


ST

Yup if the minimum is 50 quid, add the dreaded vat and the delivery,
then if thats split between a group of us etc then I'm in, I suppose
it would need a minimum of 6 of us to make this work, as it looks like
the required stuff will be about a tenner.

Hope discussing this we are not infringing any group buy policy this
group as, I know some forums I use dont allow you to discuss group
buys etc.




Can I suggest a list fo interested ppl?

if so I'll start the list........

L. Briddon.

--- In Homebrew_PCBs@yahoogroups.com, Lez <lez.briddon@...> wrote:
>
> Yup if the minimum is 50 quid, add the dreaded vat and the delivery,
> then if thats split between a group of us etc then I'm in, I suppose
> it would need a minimum of 6 of us to make this work, as it looks like
> the required stuff will be about a tenner.
> 
> Hope discussing this we are not infringing any group buy policy this
> group as, I know some forums I use dont allow you to discuss group
> buys etc.
> 
> 
> 
> 
> Can I suggest a list fo interested ppl?
> 
> if so I'll start the list........
> 
> L. Briddon.


I know there was some discusssion about the proper term, Muriatic acid
or HCL.  I checked here in the States, and I can buy a gallon of
Muriatic Acid at the hardware store for less than $3.00 USD.

I checked a chemical company and it seems the cost of a gallon of HCL
37% electronics cleaning grade, is $105.00  USD

Dave

At that price, it would be some kind of laboratory grade (reagent grade or something).  We used to buy it in bulk for oilfield use at way less than a dollar a gallon.

  ----- Original Message ----- 
  From: Dave Mucha 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Saturday, January 13, 2007 7:31 AM
  Subject: [Homebrew_PCBs] Re: "Muriatic Acid" Etymology


  --- In Homebrew_PCBs@yahoogroups.com, Lez <lez.briddon@...> wrote:
  >
  > Yup if the minimum is 50 quid, add the dreaded vat and the delivery,
  > then if thats split between a group of us etc then I'm in, I suppose
  > it would need a minimum of 6 of us to make this work, as it looks like
  > the required stuff will be about a tenner.
  > 
  > Hope discussing this we are not infringing any group buy policy this
  > group as, I know some forums I use dont allow you to discuss group
  > buys etc.
  > 
  > 
  > 
  > 
  > Can I suggest a list fo interested ppl?
  > 
  > if so I'll start the list........
  > 
  > L. Briddon.

  I know there was some discusssion about the proper term, Muriatic acid
  or HCL. I checked here in the States, and I can buy a gallon of
  Muriatic Acid at the hardware store for less than $3.00 USD.

  I checked a chemical company and it seems the cost of a gallon of HCL
  37% electronics cleaning grade, is $105.00 USD

  Dave



   

[Non-text portions of this message have been removed]

Not starting a sentence with "but", not ending a sentence with a preposition, not splitting an infinitive, and many others are artificial rules in English.  The got their start in Victorian times when the emerging middle class wanted to distinguish itself from the working class.  It is generally safe to ignore these particular rules if the sentence sounds better violating the rule.

  ----- Original Message ----- 
  From: Derryck Croker 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Saturday, January 13, 2007 5:53 AM
  Subject: Re: [Homebrew_PCBs] First PCB



  On 12 Jan 2007, at 17:46, Terry Owens wrote:

  > But (grammar; starting a sentence with 'But')

  Used in the right circumstances it is OK.

  > Being British myself, I find it offensive when someone from my 
  > country criticises the colonials in their use of English, when they 
  > patently cannot use it themselves. See corrections above.

  It gets harder and harder to spell and punctuate when there are so 
  many mistakes made - even leaving aside the country differences.

  > What has this to do with printed circuit board making?

  Quite a lot really. Can change the meaning of a sentence.

  -- 

  Cheers

  Derryck



   

[Non-text portions of this message have been removed]

> [mailto:Homebrew_PCBs@yahoogroups.com] On Behalf Of AnaLog 
> Services, Inc.
> Sent: Sunday, 14 January 2007 1:41 AM
> To: Homebrew_PCBs@yahoogroups.com
> Subject: Re: [Homebrew_PCBs] First PCB
> 
> Not starting a sentence with "but", not ending a sentence 
> with a preposition, not splitting an infinitive, and many 
> others are artificial rules in English.  The got their start 
> in Victorian times when the emerging middle class wanted to 
> distinguish itself from the working class.  It is generally 
> safe to ignore these particular rules if the sentence sounds 
> better violating the rule.
> 


Too right!  Down with all this modern crap!  If it was good enough for
great-great-great-great-grandpappy, it's good enough for the rest of ya.
Bring back vacuum tubes, F-cells and accumulators.  Silicon chips, bah
humbug.  And I'll have you know my car gets forty rods to the hogshead, and
that's the way I like it.

Someone should go & measure up Queen Lizzie, so we know how long a yard is
supposed to be.

Tony

--- "Herbert E. Plett" <cachureos@...> wrote:

> 
> --- Lez <lez.briddon@...> wrote:
> > 
> > This is all to do with bombs etc and general
> public safety, if its
> > harmful, we dont sell it, I cant imagine the
> amount of problems the
> > last bombers had to get anything..........
> 
> I guess the bombers had little or no problem getting
> what they needed, these
> laws are targeted towards the general public not for
> specifics, it's a matter
> of 'public relations'.
> We had similar ambient during our 'socialist' epoch.
> If you really need to prohibit all danger, cut off
> the water supply... just too
> many people have drowned!
> 

See http://www.dhmo.org/

- YD.


 
____________________________________________________________________________________
Cheap talk?
Check out Yahoo! Messenger's low PC-to-Phone call rates.
http://voice.yahoo.com

> > If you really need to prohibit all danger, cut off
> > the water supply... just too many people have drowned!
> > 
> 
> See http://www.dhmo.org/

oh, yes!  in our country not only milk gets contaminated with DHMO, but the
wine industry is also an abuser of DHMO.

And on-topic:
Addition of DHMO will make etching slower and less efficient.


 
____________________________________________________________________________________
Food fight? Enjoy some healthy debate 
in the Yahoo! Answers Food & Drink Q&A.
http://answers.yahoo.com/dir/?link=list&sid=396545367

In article <op.tl3ag6gsmg0lsf@tu-x2pj5qeyp2u4>,
   Stefan Trethan <stefan_trethan@...> wrote:
> On Sat, 13 Jan 2007 11:20:14 +0100, Leon <leon355@...> wrote:

> >
> > I'd be interested.
> > Leon


> Is it tricky in the UK to send chemicals via mail?

Yes, though I think some couriers will transport stuff. Even so there is a
fair bit of legal stuff to handle, which would need to be gone into, and
regulations about labelling - never mind safe packing.

When I have bought Ferric Chloride crystals in the past, they arrived
sealed inside a heavy polythene bag inside a plastic tub inside a
cardboard box. This box was further packed inside another cardboard box
with lots of soft packing material around it. The outer box had lots of
stickers on the outside detailing the hazards.

> I'd still suggest spending some time on the phone, or visiting relevant  
> places. 

Actually, the address of this place puts it about 20 miles from me so
'phoning and even collecting is easily possible. I just never got around
to it. I book-marked the link and then forgot about it. If life wasn't so
hectic at the moment I could think about it again. 

If I did collect I've get to work out how to get it to the rest of you
guys. Depending where you live I think delivery/collection/meeting "half
way" might be the best way.

Stuart.

On Jan 10, 2007, at 12:52 PM, Stefan Trethan wrote:

> Now you should look into care and feeding of this etchant as CuCl.  
> You can
> use it forever only replenishing small amounts of HCl and regenerating
> with H2O2. You will want to get H2O2 in high concentration (above  
> 20%), or
> you'll add too much water.
> How to maintain CuCl can be found in the links section, although many
> guides make it way too complicated.
> If your etchant was fuming or bubbling you probably had a much too  
> high
> concentration of one or both of the chemicals. CuCl will not cause any
> smell, or cause any rust to nearby parts, if the concentrations are  
> within
> reason and it is covered when not in use.


Last year I learned about Electrolytic Rust Removal.

To sum it up, you can add baking soda to water, drop a rusty piece of  
metal in it attached to one lead from a battery charger, and put in a  
piece of scrap metal attached to the other lead from that battery  
charger.

By forcing electrons into the 'salt' solution you have created, the  
rust on the metal you wish to reclaim is neutralized and falls off.


This process also destroys the scrap metal, causing it to rust away  
within a few days until there's nothing of it left.

The piece of metal you wanted cleaned, however, comes out of the  
'salt' bath with the rust turned black and falling off.


I bring this up because I wondered if the process could be used to  
recharge etchant.   If you put a copper rod in as the sacrificial  
scrap metal, you'd force copper into the solution.


William Carr




















[Non-text portions of this message have been removed]

On Mon, 15 Jan 2007 23:54:43 +0100, William Carr <Jkirk3279@...>  
wrote:

>
> I bring this up because I wondered if the process could be used to
> recharge etchant.   If you put a copper rod in as the sacrificial
> scrap metal, you'd force copper into the solution.
> William Carr


Actually, you use a graphite rod as one electrode, or both, since you want  
to get copper out of it not into it. I've tried it, but it doesn't work  
very well. Chlorine gas is produced at the electrode (of course! you plate  
the Cu away from CuCl). This chlorine gas would need dissolving in the  
etchant, otherwise you just pollute the air.
One suggestion to do this was a rotating electrode. i am not impressed by  
that idea. I think one should try to make a downstream gas dissolver like  
used by aquarium people to dissolve CO2. Basically a vertical tube filled  
with obstructions like marbles, gas introduced at the bottom, and a pump  
circulating water (in our case etchant) from the top to the bottom, so  
there is a downflow. This slows down the gas dramatically, giving time for  
dissolution (it could be closed up on top so any chlorine reaching the top  
would accumulate for later dissolving instead of escaping).

Who knows it may even be suffucient to catch the chlorine gas in an  
upside-down container and keep it there presented to the etchant for slow  
dissolving without any pumps. I never tried.

A simple addition may be a magnetic stirrer to stir up the static  
gas/water for faster reaction.

The way this copper recovery is done industrially is by using a membrane  
between the electrodes that allows only ions through or something like  
that, i don't fully understand the process. But it works for them.

It seems lotsa effort for little gain to me. With the small number of  
boards i do excess CuCl has never been a problem.

ST

--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@...> wrote:
>
> On Mon, 15 Jan 2007 23:54:43 +0100, William Carr <Jkirk3279@...>  
> wrote:
> 
> >
> > I bring this up because I wondered if the process could be used to
> > recharge etchant.   If you put a copper rod in as the sacrificial
> > scrap metal, you'd force copper into the solution.
> > William Carr
> 
> 
> Actually, you use a graphite rod as one electrode, or both, since
you want  
> to get copper out of it not into it. 

I've tried something similar to regenerate Ferric Chloride, using 
an Iron electrode.  I did get Copper deposited out in the form of
Copper crystals.  And, some of the Iron was dissolved into the 
solution.  However, I'm not sure if it formed Ferric Chloride or
Ferrous Chloride (or something else entirely).  I dont' remember 
evolving any Chlorine gas, although I kept the current density 
pretty low.

> I've tried it, but it doesn't work very well. 

I don't remember if I ever tried the "regenerated" solution 
(Like so many of my projects, I became distracted, and started 
working on something else.).

> Chlorine gas is produced at the electrode (of course! you plate  
> the Cu away from CuCl). 

Or reacted with the electrode material to form some nonvolatile
compound.

> This chlorine gas would need dissolving in the etchant, otherwise 
> you just pollute the air.

And poison yourself and others.  Chlorine gas is NOT something to
play around with.  It will kill you in a most unplesant way.

> One suggestion to do this was a rotating electrode. i am not
> impressed by that idea. I think one should try to make a downstream 
> gas dissolver like used by aquarium people to dissolve CO2. 

It might be a good idea to check the solubility of Chlorine in 
water first.  And, even if it dissolves, I'm not sure that's any
improvement, since it could later (when you least expect it) come
out of solution.  In my opinion, it'd be better to react it to 
a nonvolatile form.

> Basically a vertical tube filled with obstructions like marbles, 
> gas introduced at the bottom, and a pump circulating water (in our 
> case etchant) from the top to the bottom, so there is a downflow. 
> This slows down the gas dramatically, giving time for dissolution 
> (it could be closed up on top so any chlorine reaching the top  
> would accumulate for later dissolving instead of escaping).

Perhaps.  But, I'd want to work out all of the chemical equations
before even setting up a prototype operation.

> Who knows it may even be suffucient to catch the chlorine gas in an  
> upside-down container and keep it there presented to the etchant 
> for slow dissolving without any pumps. I never tried.

Perhaps.  But, from what little I've done with Chlorine gas, and
from what I know about it, I'd just as soon stay as far away from it
as I can.  That sounds too much like an accident trying to happen.

> A simple addition may be a magnetic stirrer to stir up the static  
> gas/water for faster reaction.

Magnetic stirrers might help.  Also, maintaining the correct pH
of the solution may help.  Even irridation of the Cl2 might help
it to ionize and react with something (what?).

> The way this copper recovery is done industrially is by using a 
> membrane between the electrodes that allows only ions through or 
> something like that, i don't fully understand the process. But it
> works for them.

Such membranes usually aren't cheap, nor are they usually 
inexpensive.  But, they're probably the safer way to do things.

> It seems lotsa effort for little gain to me. 

Probably.  The only reason I was looking into this was that Ferric
Chloride is a bit of a pain to obtain locally (inexpensively),
so regenerating the spent solution sounded like an interesting
option.  However, the Copper Chloride etchant sounds like an even
better idea (Note that you don't have to use the Hydrogen Peroxide
(H2O2) if you can areate the solution.).

> With the small number of  boards i do excess CuCl has never been a 
> problem.

And, even if it was, there are probably better ways of handling
that.

> ST

Dave

At 06:41 PM 1/15/2007, Stefan wrote:
>On Mon, 15 Jan 2007 23:54:43 +0100, William Carr <Jkirk3279@...>
>wrote:
>
> >
> > I bring this up because I wondered if the process could be used to
> > recharge etchant.   If you put a copper rod in as the sacrificial
> > scrap metal, you'd force copper into the solution.
> > William Carr
>
>
>Actually, you use a graphite rod as one electrode, or both, since you want
>to get copper out of it not into it. I've tried it, but it doesn't work
>very well. Chlorine gas is produced at the electrode (of course! you plate
>the Cu away from CuCl). This chlorine gas would need dissolving in the
>etchant, otherwise you just pollute the air.
><snip>

Some comments:

1. Chlorine gas is very corrosive to metals, including stainless steel. It 
is very soluble in water and very toxic.

2. If your getting chlorine released, you have the wrong electrodes, the 
wrong cell setup or too high a voltage differential.

3. Normally you make two half cells and connect them by a salt bridge. The 
salt bridge consists typically of a U-shaped tube of glass or plastic 
filled with a saturated KCl agar solution (solid, but conducts electricity).

4. If you want to eliminate the salt bridge, you need to make sure the 
right reaction occurs in the two electrodes plus liquid.

5. If one electrode is copper and the other iron, the first reaction would 
have to be Fe -> Fe++. You may end up with a solution that has FeCl2 
instead of FeCl3.

6. You should gradually increase the voltage until current starts flowing. 
If you push too high a voltage, strange reactions will start happening in 
solution.

7. The rate of reaction is determined by the area of the electrodes, the 
conductivity of the solution and temperature.

8. FeCl2 can be converted to FeCl3 via an oxidizing agent, such as H2O2, 
although this also dilutes the solution from the H2O formed.

9. The solution containing FeCl2 can also be converted to FeCl3 
electrolytically, using a salt bridge and another half-cell with a 
sacrificial electrode.

10. If you choose the sacrificial electrode properly, just closing the 
circuit can start the process without external power (you make an 
electromotive cell). E.g., the other half cell could contain iodine or 
permanganate or dichromate plus a carbon electrode.

11. Probably the simplest cell would be a graphite electrode in the etchant 
with a salt bridge to a CuSO4 solution and a copper electrode, and drive 
with sufficient voltage to force the reverse reaction.

All of these techniques involve extra chemicals and cost. One wonders 
whether or not new etchant is not cheaper.

==========================================================
Robert A. LaBudde                      Email: ral@...
824 Timberlake Drive                   Tel: (757) 467-0954
Virginia Beach, VA 23464-3239          Fax: (757) 467-2947
==========================================================

On Tue, 16 Jan 2007 01:07:55 +0100, D <wa4qal@...> wrote:

>
> It might be a good idea to check the solubility of Chlorine in
> water first.  And, even if it dissolves, I'm not sure that's any
> improvement, since it could later (when you least expect it) come
> out of solution.  In my opinion, it'd be better to react it to
> a nonvolatile form.


It's not actually just dissolved in water, it is reacted with a Cu2Cl2 to  
make two CuCl2 or something like that (i don't know nothing about  
chemistry).
The chlorine is produced too fast at the electrode or something, so it  
forms bubbles. If instead all the chlorine could be used to regenerate the  
etchant this may work well.

I know chlorine is nothing to fool around with, but i believe the tiny  
quantities created would be fairly safe to work with.

Industrial CuCl sometimes uses chlorine gas to regenerate, so there are  
ways to make this work. If one were to look at the industrial processes,  
how they get the chlorine to dissolve, the same might be done in small  
scale with the chlorine produced at the electrode making electrolytic  
regeneration a possibility.

As i said, if i would etch more i would look into it more closely, but  
chemical regeneration is so cheap it would be foolish to waste time with  
electroplating.

ST