Homebrew PCBs

I don't make a lot of boards, and most of them are quite small, so 
I've been looking for a simple, fast way to etch. After experimenting 
with a few suggested recipes, I use a 1:1 ratio of  muriatic acid 
(31.45%) to 12% hydrogen peroxide. The muriatic acid is available in 
any hardware store, the peroxide is easily obtained from a beauty 
supply store as "40 volume developer" - get the clear, not the creme. 
They are both very inexpensive, and the etching takes 1-2 minutes 
with a little hand agitation, no bubbling, no heat. DO THIS OUTDOORS 
or with a chemical hood. Then use NaOH to neutralize.

For an etching container I use a polypropylene storage bin - they 
sell them is many sizes and they are very inexpensive.

Mark

Whoops - I mean no bubbler or heater used - there is heat and 
bubbling produced by the etching process.


At 10:06 AM 6/10/2010, you wrote:

>I don't make a lot of boards, and most of them are quite small, so
>I've been looking for a simple, fast way to etch. After experimenting
>with a few suggested recipes, I use a 1:1 ratio of  muriatic acid
>(31.45%) to 12% hydrogen peroxide. The muriatic acid is available in
>any hardware store, the peroxide is easily obtained from a beauty
>supply store as "40 volume developer" - get the clear, not the creme.
>They are both very inexpensive, and the etching takes 1-2 minutes
>with a little hand agitation, no bubbling, no heat. DO THIS OUTDOORS
>or with a chemical hood. Then use NaOH to neutralize.
>
>For an etching container I use a polypropylene storage bin - they
>sell them is many sizes and they are very inexpensive.
>
>Mark
>
>
>
>------------------------------------
>
>Be sure to visit the group home and check for new Links, Files, and Photos:
>http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>

Just a note about agitation...

I used to use an aquarium aerator and an air stone for agitation.  It 
had two problems.  First, sometimes the bubbles stuck to the copper.  
This was a minor problem.

Second, though, it tends to aerosolize the etchant.  After a ver few 
boards, I realized that the heads of all nails in my storage closet had 
been etched away.

Get a small aquarium water pump.  The pump moter is very well sealed in 
plastic and drives the impeller with a magnet.  No bubbles, no aerosol.  
Salt water is corrosive and any metals dissolved in a saltwater aquarium 
become toxic, so they are pretty careful to avoid anything that will 
corrode.

Thanks for the info on the etchant.  It appears that this method is 
superior to both FeCL and ammonium persulfate (or is it perchlorate)?  
Never can remember, one etches, the other makes rocket fuel :)

On 06/10/2010 09:06 AM, Mark Lerman wrote:
> I don't make a lot of boards, and most of them are quite small, so
> I've been looking for a simple, fast way to etch. After experimenting
> with a few suggested recipes, I use a 1:1 ratio of  muriatic acid
> (31.45%) to 12% hydrogen peroxide. The muriatic acid is available in
> any hardware store, the peroxide is easily obtained from a beauty
> supply store as "40 volume developer" - get the clear, not the creme.
> They are both very inexpensive, and the etching takes 1-2 minutes
> with a little hand agitation, no bubbling, no heat. DO THIS OUTDOORS
> or with a chemical hood. Then use NaOH to neutralize.
>
> For an etching container I use a polypropylene storage bin - they
> sell them is many sizes and they are very inexpensive.
>
> Mark
>    

-- 
Our peculiar security is in the possession of a written Constitution.
Let us not make it a blank paper by construction."

    --Thomas Jefferson, letter to Wilson Nicholas, 1803

There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order.
  -- Ed Howdershelt (Author)

Mark,
I checked at my local HomeDepot and, although they had muriatic acid for swimming pools, it came in a large, two-pack container. Have you found it in smaller quantities at other hardware store? If so, where and how small? 

Also, where do you get your NaOH?

I have been vacillating between using FeCl and CuCl but I have concerned about storage and disposal for both. I am also trying to keep my quantities on hand small, so I am not storing a lot of potentially harmful liquids around my home.

Thanks. 



--- In Homebrew_PCBs@yahoogroups.com, Mark Lerman <mlerman@...> wrote:

>
> 
> Whoops - I mean no bubbler or heater used - there is heat and 
> bubbling produced by the etching process.
> 
> 
> At 10:06 AM 6/10/2010, you wrote:
> >I don't make a lot of boards, and most of them are quite small, so
> >I've been looking for a simple, fast way to etch. After experimenting
> >with a few suggested recipes, I use a 1:1 ratio of  muriatic acid
> >(31.45%) to 12% hydrogen peroxide. The muriatic acid is available in
> >any hardware store, the peroxide is easily obtained from a beauty
> >supply store as "40 volume developer" - get the clear, not the creme.
> >They are both very inexpensive, and the etching takes 1-2 minutes
> >with a little hand agitation, no bubbling, no heat. DO THIS OUTDOORS
> >or with a chemical hood. Then use NaOH to neutralize.
> >
> >For an etching container I use a polypropylene storage bin - they
> >sell them is many sizes and they are very inexpensive.
> >
> >Mark
> >
> >
> >
> >------------------------------------
> >
> >Be sure to visit the group home and check for new Links, Files, and Photos:
> >http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
> >
> >
> >
>

On 06/11/2010 10:20 AM, Frank P wrote:
> Mark,
> I checked at my local HomeDepot and, although they had muriatic acid for swimming pools, it came in a large, two-pack container. Have you found it in smaller quantities at other hardware store? If so, where and how small?
>    

Yes, but two bottles cost about $10.00.  If you find smaller amounts, 
I'll bet it costs more.  I'd think that the prudent thing to do would be 
to buy the 2 gallons, decant whatever amount you think you should use 
and use the rest to clean your driveway :)  Or, neutralize it with NaOH 
(carefully).  It's also useful for cleaning toilets :)

> Also, where do you get your NaOH?
>    

Try Drano.

> I have been vacillating between using FeCl and CuCl but I have concerned about storage and disposal for both. I am also trying to keep my quantities on hand small, so I am not storing a lot of potentially harmful liquids around my home.
>
> Thanks.
>
>
>
> --- In Homebrew_PCBs@yahoogroups.com, Mark Lerman<mlerman@...>  wrote:
>    
>>
>> Whoops - I mean no bubbler or heater used - there is heat and
>> bubbling produced by the etching process.
>>
>>
>> At 10:06 AM 6/10/2010, you wrote:
>>      
>>> I don't make a lot of boards, and most of them are quite small, so
>>> I've been looking for a simple, fast way to etch. After experimenting
>>> with a few suggested recipes, I use a 1:1 ratio of  muriatic acid
>>> (31.45%) to 12% hydrogen peroxide. The muriatic acid is available in
>>> any hardware store, the peroxide is easily obtained from a beauty
>>> supply store as "40 volume developer" - get the clear, not the creme.
>>> They are both very inexpensive, and the etching takes 1-2 minutes
>>> with a little hand agitation, no bubbling, no heat. DO THIS OUTDOORS
>>> or with a chemical hood. Then use NaOH to neutralize.
>>>
>>> For an etching container I use a polypropylene storage bin - they
>>> sell them is many sizes and they are very inexpensive.
>>>
>>> Mark
>>>
>>>
>>>
>>> ------------------------------------
>>>
>>> Be sure to visit the group home and check for new Links, Files, and Photos:
>>> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>>>
>>>
>>>
>>>        
>>      
>
>
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>
>    


-- 
Our peculiar security is in the possession of a written Constitution.
Let us not make it a blank paper by construction."

    --Thomas Jefferson, letter to Wilson Nicholas, 1803

There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order.
  -- Ed Howdershelt (Author)

I got my muriatic acid at the local hardware store - they have it in 
quart and gallon sizes.  Drano is NaOH. I keep very small amounts 
around, and mix as needed, without reusing. I'll bring the waste to 
the hazardous substances dropoff in our county when I've accumulated a bit.

Mark

At 11:20 AM 6/11/2010, you wrote:

>Mark,
>I checked at my local HomeDepot and, although they had muriatic acid 
>for swimming pools, it came in a large, two-pack container. Have you 
>found it in smaller quantities at other hardware store? If so, where 
>and how small?
>
>Also, where do you get your NaOH?
>
>I have been vacillating between using FeCl and CuCl but I have 
>concerned about storage and disposal for both. I am also trying to 
>keep my quantities on hand small, so I am not storing a lot of 
>potentially harmful liquids around my home.
>
>Thanks.
>
>
>
>--- In Homebrew_PCBs@yahoogroups.com, Mark Lerman <mlerman@...> wrote:
> >
> >
> > Whoops - I mean no bubbler or heater used - there is heat and
> > bubbling produced by the etching process.
> >
> >
> > At 10:06 AM 6/10/2010, you wrote:
> > >I don't make a lot of boards, and most of them are quite small, so
> > >I've been looking for a simple, fast way to etch. After experimenting
> > >with a few suggested recipes, I use a 1:1 ratio of  muriatic acid
> > >(31.45%) to 12% hydrogen peroxide. The muriatic acid is available in
> > >any hardware store, the peroxide is easily obtained from a beauty
> > >supply store as "40 volume developer" - get the clear, not the creme.
> > >They are both very inexpensive, and the etching takes 1-2 minutes
> > >with a little hand agitation, no bubbling, no heat. DO THIS OUTDOORS
> > >or with a chemical hood. Then use NaOH to neutralize.
> > >
> > >For an etching container I use a polypropylene storage bin - they
> > >sell them is many sizes and they are very inexpensive.
> > >
> > >Mark
> > >
> > >
> > >
> > >------------------------------------
> > >
> > >Be sure to visit the group home and check for new Links, Files, 
> and Photos:
> > >http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
> > >
> > >
> > >
> >
>
>
>
>
>------------------------------------
>
>Be sure to visit the group home and check for new Links, Files, and Photos:
>http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>

--- In Homebrew_PCBs@yahoogroups.com, Mark Lerman <mlerman@...> wrote:
>
> I don't make a lot of boards, and most of them are quite small, so 
> I've been looking for a simple, fast way to etch. After experimenting 
> with a few suggested recipes, I use a 1:1 ratio of  muriatic acid 
> (31.45%) to 12% hydrogen peroxide. The muriatic acid is available in 
> any hardware store, the peroxide is easily obtained from a beauty 
> supply store as "40 volume developer" - get the clear, not the creme. 
> They are both very inexpensive, and the etching takes 1-2 minutes 
> with a little hand agitation, no bubbling, no heat. DO THIS OUTDOORS 
> or with a chemical hood. Then use NaOH to neutralize.
> 
> For an etching container I use a polypropylene storage bin - they 
> sell them is many sizes and they are very inexpensive.
> 
> Mark
>


This is what I used to start with, it was very fast, the nice thing is it converts to cupric chloride after you use it enough and that stuff you can keep using over and over.

Most any hardware store should carry it.  Big box stores need to deal in large volumes to keep the margins up -- try a local hardware.

I'm not sure what you want the NaOH for.  You can use that to neutralise FeCl when you want to dispose of it, but for CuCl, all you need is H2O2 (hydrogen peroxide) from the druggist (3%) or beauty supply (12%) is better.

HTH,
Donald.
--
"Plain Text" email -- it's an accessibility issue
()  no proprietary attachments; no html mail
/\  ascii ribbon campaign - <www.asciiribbon.org>

----- "Frank P" <qz9090@...> wrote:

> Mark,
> I checked at my local HomeDepot and, although they had muriatic acid
> for swimming pools, it came in a large, two-pack container. Have you
> found it in smaller quantities at other hardware store? If so, where
> and how small? 
> 
> Also, where do you get your NaOH?
> 
> I have been vacillating between using FeCl and CuCl but I have
> concerned about storage and disposal for both. I am also trying to
> keep my quantities on hand small, so I am not storing a lot of
> potentially harmful liquids around my home.
> 
> Thanks. 
> 
> 
> 
> --- In Homebrew_PCBs@yahoogroups.com, Mark Lerman <mlerman@...>
> wrote:
> >
> > 
> > Whoops - I mean no bubbler or heater used - there is heat and 
> > bubbling produced by the etching process.
> > 
> > 
> > At 10:06 AM 6/10/2010, you wrote:
> > >I don't make a lot of boards, and most of them are quite small, so
> > >I've been looking for a simple, fast way to etch. After
> experimenting
> > >with a few suggested recipes, I use a 1:1 ratio of  muriatic acid
> > >(31.45%) to 12% hydrogen peroxide. The muriatic acid is available
> in
> > >any hardware store, the peroxide is easily obtained from a beauty
> > >supply store as "40 volume developer" - get the clear, not the
> creme.
> > >They are both very inexpensive, and the etching takes 1-2 minutes
> > >with a little hand agitation, no bubbling, no heat. DO THIS
> OUTDOORS
> > >or with a chemical hood. Then use NaOH to neutralize.
> > >
> > >For an etching container I use a polypropylene storage bin - they
> > >sell them is many sizes and they are very inexpensive.
> > >
> > >Mark
> > >
> > >
> > >
> > >------------------------------------
> > >
> > >Be sure to visit the group home and check for new Links, Files, and
> Photos:
> > >http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
> > >
> > >
> > >
> >
> 
> 
> 
> 
> ------------------------------------
> 
> Be sure to visit the group home and check for new Links, Files, and
> Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
> 
> 
>

Mark Lerman wrote:
> I don't make a lot of boards, and most of them are quite small, so 
> I've been looking for a simple, fast way to etch. After experimenting 
> with a few suggested recipes, I use a 1:1 ratio of  muriatic acid 
> (31.45%) to 12% hydrogen peroxide. 
It's been 60 years since Chem 101, and I don't recall  - do I add the 
acid to the H2O2 (water), or the other way around?
Also - someone mentioned a magnetically coupled aquarium pump for liquid 
agitation.  Is this an easily found item?  All I've seen in pet stores 
are the air bubbler pumps.

Norm
W6NIM

On 12/06/2010 01:22, Donald H Locker wrote:
> Most any hardware store should carry it.  Big box stores need to deal in large volumes to keep the margins up -- try a local hardware.
>
> I'm not sure what you want the NaOH for.  You can use that to neutralise FeCl when you want to dispose of it, but for CuCl, all you need is H2O2 (hydrogen peroxide) from the druggist (3%) or beauty supply (12%) is better.

NaOH is often used for developing the resist after UV exposure. I buy 
mine from the local hardware store.

Leon
-- 
Leon Heller
G1HSM

Disposal note...

I had to say we are wery 'eco friendly'.
I etch my board with Hcl and H2O2. For 10x10cm board I use aprox 5ml of 
H2O(tap water), 1ml of HCl(30%) and 1ml of H2O2(30%).

So aprox 2 to 3 years I need to buy new bootle (1 liter) of both.

Now look to disposal problem.

The average household drain HCl in sinks/toilets as cleaner(near all 
cleaner use HCl) in amount much larger that mine is. The quantity is so 
smal so if someone throu up (maybe to much beer) the HCl pollution is 
bigger. So I don't care and throw that into sink. The other content 
H2O2. You may look in two sides. The all hair paint use H2O2 in large 
quantity and throw that stuff into sink directly. Every unnatural 
blondie use much more H2O2 than I. In the other way if we let H2O2 on 
sun few day they completly disentigrate into H2O and O2. So I can say 
that source chemical used is so small that we can just sink em. ..and 
use a loot of watter to dilute it. The worst contaminant is byproduct 
CuCl. And again. The content is so small and we can throw it. The 
average wineagre yard near me use so much CuCl so my quantity is way way 
lower. And someone will say that all that sink output goes into sea. 
CuCl is extensively used to paint boat's to prevent algae sticking on it.


But if you think that we must be the 1'st one to preserve planet then 
you have simple solution how you can dispose the used solution.
Just get one glass jar as low and flat as you can. Put it onto sun and 
pour all chemicals used from pcb etchng into it. Then cover it with 
glass plate little raised. So all thing will evaporate on sun and leave 
the worst (CuCl) as little blue/green sand. When you collect much of 
that than just dispose that in chemichal dispossing containers. But for 
100grams you need to etch a lot of boards.(years)

...But this work's just if you use smallest quantity possible. I see a 
lot of folks use just to much etchant. If you check youtube you can see 
that a lot of users use so big quantity of etchant. So the key is smal 
quantity and smal bath. I use the plastic kontainers for food / ice 
cream. It should have flat bottom and be just right size. (I have 4 
different size) So just use smalest one and use as little etchant as I 
can. ..just to cover the PCB not more. And etch it outside with wind 
blowing in you back. When etching the small content of chlorine gas is 
developed. You don't want to breath that. The etching time is 2 to 3 
minute. And use cold watter. As reaction is exotermic (release heat) the 
solution wil heat up itself. If you use hot watter in start the solution 
will boil when etching and that exesive heat may destroy your image etched.

Thanks for reading and sorry for my ugly english.

do I add the 
> acid to the H2O2 (water), or the other way around?

ALWAYS add the acid to the H2O2 - MUCH safer.

Ken H>

On 06/12/2010 01:46 AM, Norm wrote:
> It's been 60 years since Chem 101, and I don't recall  - do I add the
> acid to the H2O2 (water), or the other way around?

Do as you ought'er
add acid to water


If you add a small amount of water to a large amount of acid, the water 
almost immediately boils and the steam bubbles will throw acid all over 
the place.  Very bad.

On 06/12/2010 03:11 AM, Leon Heller wrote:
> NaOH is often used for developing the resist after UV exposure.

I use Na2C03 (sodium carbonate, or washing soda) for developing, and 
NaOH for stripping.  NaOH is also used in titration, to determine the H+ 
concentration in CuCl etchant.

Ken & DJ -

Thanks.  I knew one way was liable to cause trouble, but it's surprising 
how much one can forget in 70+ years!  Just getting back into PC fab.  
My experience was with negatives, UV exposure,  KPR and FeCl3 back in 
the '70s, but the toner transfer and CuCl looks interesting, especially 
now that the volatile resists and developers are considered 
environmentally unfriendly.

Norm

On 06/12/2010 08:48 PM, Norm wrote:

> now that the volatile resists and developers are considered
> environmentally unfriendly.

The "eco-friendliness" is honestly irrelevant. I think the new methods 
are just so much more effective and reliable.

bye
as

Donald, 
Please see my responses below...

> Most any hardware store should carry it.  Big box stores need to deal in large volumes to keep the margins up -- try a local hardware.

I called an old hardware store (now an Ace Hardware) in my area and they told me they carry muriatic acid in one quart containers! Thanks.

> I'm not sure what you want the NaOH for.  You can use that to neutralise FeCl when you want to dispose of it, but for CuCl, all you need is H2O2 (hydrogen peroxide) from the druggist (3%) or beauty supply (12%) is better.

The muriatic acid/H2O2 solution is used for etching, is it not?
If you can "re-charge" the etching solution by adding H2O2 whenever you get ready to etch a board (I think someone else said this), I guess you may not need the NaOH (Drano) to neutralize the solution for a while. 

Of course, that raises the question, when should I be disposing of my etching solution? How do I know it is "spent" and is no longer useful?

For storage, I believe a glass bottle is best (taking great care in protecting the metal cap).

Unless things change, it looks like I'm going to be using muriatic acid/H2O2 as an etching solution. Although, the 1:1 ratio stated by Mark seems a bit strong. I have to check on this....

On Sun, 13 Jun 2010 19:35:34 -0000, you wrote:

>Donald, 
>Please see my responses below...
>
>> Most any hardware store should carry it.  Big box stores need to deal in large volumes to keep the margins up -- try a local hardware.
>
>I called an old hardware store (now an Ace Hardware) in my area and they told me they carry muriatic acid in one quart containers! Thanks.
>
>> I'm not sure what you want the NaOH for.  You can use that to neutralise FeCl when you want to dispose of it, but for CuCl, all you need is H2O2 (hydrogen peroxide) from the druggist (3%) or beauty supply (12%) is better.
>
>The muriatic acid/H2O2 solution is used for etching, is it not?
>If you can "re-charge" the etching solution by adding H2O2 whenever you get ready to etch a board (I think someone else said this), I guess you may not need the NaOH (Drano) to neutralize the solution for a while. 
>
>Of course, that raises the question, when should I be disposing of my etching solution? How do I know it is "spent" and is no longer useful?
>
>For storage, I believe a glass bottle is best (taking great care in protecting the metal cap).
>
>Unless things change, it looks like I'm going to be using muriatic acid/H2O2 as an etching solution. Although, the 1:1 ratio stated by Mark seems a bit strong. I have to check on this....

Quite strong.  I use 30% Muriatic acid, and the 3% H2O2 mixed in a
ratio of one part acid to four parts H2O2.

It will die after about 4 weeks, be weak after 2.  Adding H2O2 will
help, so will bubbling air through it.  After a bit of use it converts
to CuCl etchant, which always needs air bubbled through it, but lasts
virtually forever.

I like glass bottles, but not with metal caps.  Plastic food
containers work well, though.


Harvey

>
>
>
>
>
>------------------------------------
>
>Be sure to visit the group home and check for new Links, Files, and Photos:
>http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>

About the use of muriatic acid and H2O2:

It looks like most of you use 30% muriatic acid
added to 12% H2O2.

Do you then use that mixture as-is, or dilute that
mixture down with water?  If so, how much?

- Jim W4ENE

I think many concentrations and mixtures will work. I've used 2 parts 3% H2O2 to 1 part HCl (30%) and it works fine, but it often takes 20-40 minutes to etch. I usually do my etching outside in between doing other things, so I like it done fast. The 1:1 of 12% H2O2 to 31% (approx) HCl is very fast, and suits my personality <smile>. I would suggest you experiment and see what works best for you.

Mark


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

>From: Jim Tonne <tonne@...>
>Sent: Jun 13, 2010 4:48 PM
>To: Homebrew_PCBs@yahoogroups.com
>Subject: Re: [Homebrew_PCBs] Re: Etching note
>
>
>About the use of muriatic acid and H2O2:
>
>It looks like most of you use 30% muriatic acid
>added to 12% H2O2.
>
>Do you then use that mixture as-is, or dilute that
>mixture down with water?  If so, how much?
>
>- Jim W4ENE
>
>
>
>------------------------------------
>
>Be sure to visit the group home and check for new Links, Files, and Photos:
>http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>

I think others have covered the bases pretty well.  Until you stop doing etching, I don't see any reason to dispose of the HCl/H2O2 brew.  Regenerate it with more H2O2 (or oxygen) and use again.

Donald.
--
"Plain Text" email -- it's an accessibility issue
()  no proprietary attachments; no html mail
/\  ascii ribbon campaign - <www.asciiribbon.org>

----- "Frank P" <qz9090@...> wrote:

> Donald, 
> Please see my responses below...
> 
> > Most any hardware store should carry it.  Big box stores need to
> deal in large volumes to keep the margins up -- try a local hardware.
> 
> I called an old hardware store (now an Ace Hardware) in my area and
> they told me they carry muriatic acid in one quart containers!
> Thanks.
> 
> > I'm not sure what you want the NaOH for.  You can use that to
> neutralise FeCl when you want to dispose of it, but for CuCl, all you
> need is H2O2 (hydrogen peroxide) from the druggist (3%) or beauty
> supply (12%) is better.
> 
> The muriatic acid/H2O2 solution is used for etching, is it not?
> If you can "re-charge" the etching solution by adding H2O2 whenever
> you get ready to etch a board (I think someone else said this), I
> guess you may not need the NaOH (Drano) to neutralize the solution for
> a while. 
> 
> Of course, that raises the question, when should I be disposing of my
> etching solution? How do I know it is "spent" and is no longer
> useful?
> 
> For storage, I believe a glass bottle is best (taking great care in
> protecting the metal cap).
> 
> Unless things change, it looks like I'm going to be using muriatic
> acid/H2O2 as an etching solution. Although, the 1:1 ratio stated by
> Mark seems a bit strong. I have to check on this....
> 
> 
> 
> 
> 
> ------------------------------------
> 
> Be sure to visit the group home and check for new Links, Files, and
> Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
> 
> 
>

Petsmart typically has them.

If you can't find them there, try:


http://www.drsfostersmith.com 
<http://www.drsfostersmith.com/?ref=4397&subref=AA&mkwid=SGISyNsuF%7Cpcrid%7C4214695761&cmpid=PPC-_-G-_-4397>

Specifically:

http://www.fosterandsmithaquatics.com/fish-supplies/aquarium-pumps/ps/c/3578/4587

And, as a suggestion:

http://www.fosterandsmithaquatics.com/product/prod_display.cfm?c=3578+4587+4671&pcatid=4671 
<http://www.fosterandsmithaquatics.com/product/prod_display.cfm?c=3578+4587+4671&pcatid=4671>

Note, the above is after a pretty quick search, but you want something 
on the low end of gallons / hour.

On 06/12/2010 12:46 AM, Norm wrote:
> Mark Lerman wrote:
>    
>> I don't make a lot of boards, and most of them are quite small, so
>> I've been looking for a simple, fast way to etch. After experimenting
>> with a few suggested recipes, I use a 1:1 ratio of  muriatic acid
>> (31.45%) to 12% hydrogen peroxide.
>>      
> It's been 60 years since Chem 101, and I don't recall  - do I add the
> acid to the H2O2 (water), or the other way around?
> Also - someone mentioned a magnetically coupled aquarium pump for liquid
> agitation.  Is this an easily found item?  All I've seen in pet stores
> are the air bubbler pumps.
>
> Norm
> W6NIM
>
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>
>    


-- 
Our peculiar security is in the possession of a written Constitution.
Let us not make it a blank paper by construction."

    --Thomas Jefferson, letter to Wilson Nicholas, 1803

There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order.
  -- Ed Howdershelt (Author)



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

In my opinion:

H2O2 doesn't stay H2O2 for long.  It is likely mostly H2O by the time it 
reaches the sewer plant.

HCl?  As you say, not a huge problem, it tends to lower pH, which may be 
precisely what the sewer plant wants and I'd not be surprised if they 
didn't use the stuff themselves.

The worst thing in the effluent from etching may well be CuCl, which is 
pretty toxic to crustacea, snails and perhaps (guessing) bacteria, which 
is why some folks neutralize it with NsOH (Drano) before dumping it.

Of all the things you could poor down your drain, HCl is likely the most 
innocuous.




On 06/12/2010 02:38 AM, Slavko Kocjancic wrote:


> Disposal note...
>
> I had to say we are wery 'eco friendly'.
> I etch my board with Hcl and H2O2. For 10x10cm board I use aprox 5ml of
> H2O(tap water), 1ml of HCl(30%) and 1ml of H2O2(30%).
>
> So aprox 2 to 3 years I need to buy new bootle (1 liter) of both.
>
> Now look to disposal problem.
>
> The average household drain HCl in sinks/toilets as cleaner(near all
> cleaner use HCl) in amount much larger that mine is. The quantity is so
> smal so if someone throu up (maybe to much beer) the HCl pollution is
> bigger. So I don't care and throw that into sink. The other content
> H2O2. You may look in two sides. The all hair paint use H2O2 in large
> quantity and throw that stuff into sink directly. Every unnatural
> blondie use much more H2O2 than I. In the other way if we let H2O2 on
> sun few day they completly disentigrate into H2O and O2. So I can say
> that source chemical used is so small that we can just sink em. ..and
> use a loot of watter to dilute it. The worst contaminant is byproduct
> CuCl. And again. The content is so small and we can throw it. The
> average wineagre yard near me use so much CuCl so my quantity is way way
> lower. And someone will say that all that sink output goes into sea.
> CuCl is extensively used to paint boat's to prevent algae sticking on it.
>
>
> But if you think that we must be the 1'st one to preserve planet then
> you have simple solution how you can dispose the used solution.
> Just get one glass jar as low and flat as you can. Put it onto sun and
> pour all chemicals used from pcb etchng into it. Then cover it with
> glass plate little raised. So all thing will evaporate on sun and leave
> the worst (CuCl) as little blue/green sand. When you collect much of
> that than just dispose that in chemichal dispossing containers. But for
> 100grams you need to etch a lot of boards.(years)
>
> ...But this work's just if you use smallest quantity possible. I see a
> lot of folks use just to much etchant. If you check youtube you can see
> that a lot of users use so big quantity of etchant. So the key is smal
> quantity and smal bath. I use the plastic kontainers for food / ice
> cream. It should have flat bottom and be just right size. (I have 4
> different size) So just use smalest one and use as little etchant as I
> can. ..just to cover the PCB not more. And etch it outside with wind
> blowing in you back. When etching the small content of chlorine gas is
> developed. You don't want to breath that. The etching time is 2 to 3
> minute. And use cold watter. As reaction is exotermic (release heat) the
> solution wil heat up itself. If you use hot watter in start the solution
> will boil when etching and that exesive heat may destroy your image etched.
>
> Thanks for reading and sorry for my ugly english.
>
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>
>    


-- 
Our peculiar security is in the possession of a written Constitution.
Let us not make it a blank paper by construction."

    --Thomas Jefferson, letter to Wilson Nicholas, 1803

There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order.
  -- Ed Howdershelt (Author)

On 06/13/2010 02:35 PM, Frank P wrote:
> Donald,
> Please see my responses below...
>
>    
>> Most any hardware store should carry it.  Big box stores need to deal in large volumes to keep the margins up -- try a local hardware.
>>      
> I called an old hardware store (now an Ace Hardware) in my area and they told me they carry muriatic acid in one quart containers! Thanks.
>
>    
>> I'm not sure what you want the NaOH for.  You can use that to neutralise FeCl when you want to dispose of it, but for CuCl, all you need is H2O2 (hydrogen peroxide) from the druggist (3%) or beauty supply (12%) is better.
>>      
> The muriatic acid/H2O2 solution is used for etching, is it not?
> If you can "re-charge" the etching solution by adding H2O2 whenever you get ready to etch a board (I think someone else said this), I guess you may not need the NaOH (Drano) to neutralize the solution for a while.
>
> Of course, that raises the question, when should I be disposing of my etching solution? How do I know it is "spent" and is no longer useful?
>    

Wondering that myself.  I suppose the easy answer is "when it stops 
etching to your expectatins".  Also is probably a reason bubbling air is 
better than H2O2, but bubbling creates corrosive aerosols.



> For storage, I believe a glass bottle is best (taking great care in protecting the metal cap).
>    

It depends on your metric.  Glass breaks easier than plastic.  There is 
nothing intrinsically wrong with plastic.  There are reasons the stuff 
is distributed in plastic bottles.  Anything should be better than a 
metal cap.

> Unless things change, it looks like I'm going to be using muriatic acid/H2O2 as an etching solution. Although, the 1:1 ratio stated by Mark seems a bit strong. I have to check on this....
>
>
>
>
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>
>    


-- 
Our peculiar security is in the possession of a written Constitution.
Let us not make it a blank paper by construction."

    --Thomas Jefferson, letter to Wilson Nicholas, 1803

There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order.
  -- Ed Howdershelt (Author)

--- In Homebrew_PCBs@yahoogroups.com, "Dale J. Chatham" <dale@...> wrote:
>
> In my opinion:
> 
> H2O2 doesn't stay H2O2 for long.  It is likely mostly H2O by the time it 
> reaches the sewer plant.
> 
> HCl?  As you say, not a huge problem, it tends to lower pH, which may be 
> precisely what the sewer plant wants and I'd not be surprised if they 
> didn't use the stuff themselves.
> 
> The worst thing in the effluent from etching may well be CuCl, which is 
> pretty toxic to crustacea, snails and perhaps (guessing) bacteria, which 
> is why some folks neutralize it with NsOH (Drano) before dumping it.
> 
> Of all the things you could poor down your drain, HCl is likely the most 
> innocuous.
> 
> 
>


It will corrode the crap out of *any* metal fittings, even stainless. Trust me on that one, I rinsed off a PCB in the sink and the tiny amount that dripped off the board left rust spots on the drain surround. I now mix up a pitcher of water with some baking soda in it and use that to rinse things off.

Anything with dissolved copper should not be dumped down the drain, at least if you live in a coastal area like I do where the water eventually ends up in the ocean.

> 
> Wondering that myself.  I suppose the easy answer is "when it stops 
> etching to your expectatins".  Also is probably a reason bubbling air is 
> better than H2O2, but bubbling creates corrosive aerosols.
> 



They both work fine. Once it's turned into cupric chloride, it doesn't matter of the peroxide breaks down. You just add a capfull prior to etching if you don't want to wait around for air to regenerate it. It's cool, it almost instantly changes from very dark brownish-green to light green.

On 06/14/2010 12:09 PM, James wrote:
>
> --- In Homebrew_PCBs@yahoogroups.com, "Dale J. Chatham"<dale@...>  wrote:
>    
>> In my opinion:
>>
>> H2O2 doesn't stay H2O2 for long.  It is likely mostly H2O by the time it
>> reaches the sewer plant.
>>
>> HCl?  As you say, not a huge problem, it tends to lower pH, which may be
>> precisely what the sewer plant wants and I'd not be surprised if they
>> didn't use the stuff themselves.
>>
>> The worst thing in the effluent from etching may well be CuCl, which is
>> pretty toxic to crustacea, snails and perhaps (guessing) bacteria, which
>> is why some folks neutralize it with NsOH (Drano) before dumping it.
>>
>> Of all the things you could poor down your drain, HCl is likely the most
>> innocuous.
>>
>>
>>
>>      
>
> It will corrode the crap out of *any* metal fittings, even stainless. Trust me on that one, I rinsed off a PCB in the sink and the tiny amount that dripped off the board left rust spots on the drain surround. I now mix up a pitcher of water with some baking soda in it and use that to rinse things off.
>
> Anything with dissolved copper should not be dumped down the drain, at least if you live in a coastal area like I do where the water eventually ends up in the ocean.
>    

Well, I thought we were talking about environmental impact.  I stand by 
my statement that HCl is probably the most innocuous thing you can dump 
down the sink, in that regard.  It's difficult to make myself remember 
that folks have metal pipes for drainage :)  Even when my goosenecks 
were metal, I'd replace them with PVC just 'cause.

>
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>
>    


-- 
Our peculiar security is in the possession of a written Constitution.
Let us not make it a blank paper by construction."

    --Thomas Jefferson, letter to Wilson Nicholas, 1803

There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order.
  -- Ed Howdershelt (Author)

On 06/14/2010 12:12 PM, James wrote:
>    
>> Wondering that myself.  I suppose the easy answer is "when it stops
>> etching to your expectatins".  Also is probably a reason bubbling air is
>> better than H2O2, but bubbling creates corrosive aerosols.
>>
>>      
>
>
> They both work fine. Once it's turned into cupric chloride, it doesn't matter of the peroxide breaks down. You just add a capfull prior to etching if you don't want to wait around for air to regenerate it. It's cool, it almost instantly changes from very dark brownish-green to light green.
>    

This is my understanding of the process, I could be terribly wrong.

Etching produces

2 Cu + 2 HCl -> 2 CuCl + H2.

Adding the H2O2 gives the following:

H2 + 3 H2O2 -> 4 H2O + O2

You also wind up with this one if there is any "head space" in the 
container:

2 H2O2 -> 2 H2O + O2.

Adding H2O merely regenerates the source of quickly available Oxygen 
molecules.

I can't make the H2O2 produce HCl, but it's been a while.

:)

Hence, my assumption that sooner or later, you're gonna need to dump the 
stuff and start over.

-- 
Our peculiar security is in the possession of a written Constitution.
Let us not make it a blank paper by construction."

    --Thomas Jefferson, letter to Wilson Nicholas, 1803

There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order.
  -- Ed Howdershelt (Author)

> 
> I can't make the H2O2 produce HCl, but it's been a while.
> 
> :)
> 
> Hence, my assumption that sooner or later, you're gonna need to dump the 
> stuff and start over.
> 
>



HCl is consumed, you don't need to dump the stuff and start over, you simply add a bit more HCl and you're on your way again. I've etched a lot of boards and haven't had to add any yet though.

An estimated 0.34 billion metric tons of copper currently exists in the ocean’s waters based on a concentration of 0.25 ug/L and a volume of 1.338 x 109 km3
From MadSci Network, Internet site,
“www.madsci.org”

That's a lot of printed circuit boads

I don't suffer from insanity I enjoy it!

--- On Mon, 6/14/10, James <jamesrsweet@...> wrote:

From: James <jamesrsweet@...>
Subject: [Homebrew_PCBs] Re: Etching note
To: Homebrew_PCBs@yahoogroups.com
Date: Monday, June 14, 2010, 6:09 PM







 



  


    
      
      
      



--- In Homebrew_PCBs@yahoogroups.com, "Dale J. Chatham" <dale@...> wrote:

>

> In my opinion:

> 

> H2O2 doesn't stay H2O2 for long.  It is likely mostly H2O by the time it 

> reaches the sewer plant.

> 

> HCl?  As you say, not a huge problem, it tends to lower pH, which may be 

> precisely what the sewer plant wants and I'd not be surprised if they 

> didn't use the stuff themselves.

> 

> The worst thing in the effluent from etching may well be CuCl, which is 

> pretty toxic to crustacea, snails and perhaps (guessing) bacteria, which 

> is why some folks neutralize it with NsOH (Drano) before dumping it.

> 

> Of all the things you could poor down your drain, HCl is likely the most 

> innocuous.

> 

> 

>



It will corrode the crap out of *any* metal fittings, even stainless. Trust me on that one, I rinsed off a PCB in the sink and the tiny amount that dripped off the board left rust spots on the drain surround. I now mix up a pitcher of water with some baking soda in it and use that to rinse things off.



Anything with dissolved copper should not be dumped down the drain, at least if you live in a coastal area like I do where the water eventually ends up in the ocean. 





    
     

    
    


 



  






      

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

Harvey,
Would you give some examples of the "plastic food containers" you mentioned? And, how long it could be stored in those containers?

Thanks.



--- In Homebrew_PCBs@yahoogroups.com, Harvey White <madyn@...> wrote:

>
> On Sun, 13 Jun 2010 19:35:34 -0000, you wrote:
> 
> >Donald, 
> >Please see my responses below...
> >
> >> Most any hardware store should carry it.  Big box stores need to deal in large volumes to keep the margins up -- try a local hardware.
> >
> >I called an old hardware store (now an Ace Hardware) in my area and they told me they carry muriatic acid in one quart containers! Thanks.
> >
> >> I'm not sure what you want the NaOH for.  You can use that to neutralise FeCl when you want to dispose of it, but for CuCl, all you need is H2O2 (hydrogen peroxide) from the druggist (3%) or beauty supply (12%) is better.
> >
> >The muriatic acid/H2O2 solution is used for etching, is it not?
> >If you can "re-charge" the etching solution by adding H2O2 whenever you get ready to etch a board (I think someone else said this), I guess you may not need the NaOH (Drano) to neutralize the solution for a while. 
> >
> >Of course, that raises the question, when should I be disposing of my etching solution? How do I know it is "spent" and is no longer useful?
> >
> >For storage, I believe a glass bottle is best (taking great care in protecting the metal cap).
> >
> >Unless things change, it looks like I'm going to be using muriatic acid/H2O2 as an etching solution. Although, the 1:1 ratio stated by Mark seems a bit strong. I have to check on this....
> 
> Quite strong.  I use 30% Muriatic acid, and the 3% H2O2 mixed in a
> ratio of one part acid to four parts H2O2.
> 
> It will die after about 4 weeks, be weak after 2.  Adding H2O2 will
> help, so will bubbling air through it.  After a bit of use it converts
> to CuCl etchant, which always needs air bubbled through it, but lasts
> virtually forever.
> 
> I like glass bottles, but not with metal caps.  Plastic food
> containers work well, though.
> 
> 
> Harvey
> 
> >
> >
> >
> >
> >
> >------------------------------------
> >
> >Be sure to visit the group home and check for new Links, Files, and Photos:
> >http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
> >
> >
> >
>

Malcolm Parker-Lisberg wrote:
> An estimated 0.34 billion metric tons of copper currently exists in the ocean\u2019s waters based on a concentration of 0.25 ug/L and a volume of 1.338 x 109 km3
> >From MadSci Network, Internet site,
> \u201cwww.madsci.org\u201d
>
> That's a lot of printed circuit boads
>
>   
Cu and CuCl are two different things.  There's plenty of copper and 
plenty of chlorine in the oceans, but there's plenty of carbon and 
plenty of nitrogen in the atmosphere, but thankfully, not much CN (cyanide)

Kerry

On 06/14/2010 12:34 PM, James wrote:
>    
>> I can't make the H2O2 produce HCl, but it's been a while.
>>
>> :)
>>
>> Hence, my assumption that sooner or later, you're gonna need to dump the
>> stuff and start over.
>>
>>
>>      
>
>
> HCl is consumed, you don't need to dump the stuff and start over, you simply add a bit more HCl and you're on your way again. I've etched a lot of boards and haven't had to add any yet though.
>
>    

OK, that works.  But, you just can't keep on adding HCl and I rather 
suspect that eventually, you decant some of the stuff and get rid of it, 
else given enough boards you'd be swimming in it.  Er, maybe not 
literally :)

-- 
Our peculiar security is in the possession of a written Constitution.
Let us not make it a blank paper by construction."

    --Thomas Jefferson, letter to Wilson Nicholas, 1803

There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order.
  -- Ed Howdershelt (Author)

On 06/14/2010 12:48 PM, Malcolm Parker-Lisberg wrote:
> An estimated 0.34 billion metric tons of copper currently exists in the ocean\u2019s waters based on a concentration of 0.25 ug/L and a volume of 1.338 x 109 km3
>  From MadSci Network, Internet site,
> \u201cwww.madsci.org\u201d
>
> That's a lot of printed circuit boads
>
>    

Copper is death to invertebrates in the ocean. Primarily, that means 
coral, shrimp, crabs, ... While your concentrations are correct as an 
average, close to the places where the effluent water (and I mean 
processed and safe as far as sewage is considered) will have higher 
concentrations.

The stuff really should be kept out of the ocean. Of course, if you live 
near Louisiana, Mississippi, Alabama or Florida right now, it probably 
doesn't reall matter all that much.

-- 
Our peculiar security is in the possession of a written Constitution.
Let us not make it a blank paper by construction."

    --Thomas Jefferson, letter to Wilson Nicholas, 1803

There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order.
  -- Ed Howdershelt (Author)

On Mon, 14 Jun 2010 17:56:35 -0000, you wrote:

>Harvey,
>Would you give some examples of the "plastic food containers" you mentioned? And, how long it could be stored in those containers?

Rubbermaid cereal container, holds roughly 1 1/2 gallons.  Has stored
Ferric Chloride for over a  year, CUCL for a month or three.

Ferric Chloride did eat the rubber gasket on one container (walmart,
not Rubbermaid), these are plastic to plastic.

Harvey

>
>Thanks.
>
>
>
>--- In Homebrew_PCBs@yahoogroups.com, Harvey White <madyn@...> wrote:
>>
>> On Sun, 13 Jun 2010 19:35:34 -0000, you wrote:
>> 
>> >Donald, 
>> >Please see my responses below...
>> >
>> >> Most any hardware store should carry it.  Big box stores need to deal in large volumes to keep the margins up -- try a local hardware.
>> >
>> >I called an old hardware store (now an Ace Hardware) in my area and they told me they carry muriatic acid in one quart containers! Thanks.
>> >
>> >> I'm not sure what you want the NaOH for.  You can use that to neutralise FeCl when you want to dispose of it, but for CuCl, all you need is H2O2 (hydrogen peroxide) from the druggist (3%) or beauty supply (12%) is better.
>> >
>> >The muriatic acid/H2O2 solution is used for etching, is it not?
>> >If you can "re-charge" the etching solution by adding H2O2 whenever you get ready to etch a board (I think someone else said this), I guess you may not need the NaOH (Drano) to neutralize the solution for a while. 
>> >
>> >Of course, that raises the question, when should I be disposing of my etching solution? How do I know it is "spent" and is no longer useful?
>> >
>> >For storage, I believe a glass bottle is best (taking great care in protecting the metal cap).
>> >
>> >Unless things change, it looks like I'm going to be using muriatic acid/H2O2 as an etching solution. Although, the 1:1 ratio stated by Mark seems a bit strong. I have to check on this....
>> 
>> Quite strong.  I use 30% Muriatic acid, and the 3% H2O2 mixed in a
>> ratio of one part acid to four parts H2O2.
>> 
>> It will die after about 4 weeks, be weak after 2.  Adding H2O2 will
>> help, so will bubbling air through it.  After a bit of use it converts
>> to CuCl etchant, which always needs air bubbled through it, but lasts
>> virtually forever.
>> 
>> I like glass bottles, but not with metal caps.  Plastic food
>> containers work well, though.
>> 
>> 
>> Harvey
>> 
>> >
>> >
>> >
>> >
>> >
>> >------------------------------------
>> >
>> >Be sure to visit the group home and check for new Links, Files, and Photos:
>> >http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>> >
>> >
>> >
>>
>
>
>
>
>------------------------------------
>
>Be sure to visit the group home and check for new Links, Files, and Photos:
>http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>

Copper chloride is produced in the sea and a high concentrations is  indeed a roblem, at less than lethal concentrations it reduces growth. One published paper demonstrates how Krill have adapted to its presence and secrete it. It is high concentrations on an industrial scale that causes problems not low concentrations from litre quantaties.

I don't suffer from insanity I enjoy it!

--- On Mon, 6/14/10, Dale J. Chatham <dale@...> wrote:

From: Dale J. Chatham <dale@...>
Subject: Re: [Homebrew_PCBs] Re: Etching note
To: Homebrew_PCBs@yahoogroups.com
Cc: "Malcolm Parker-Lisberg" <mparkerlisberg@...>
Date: Monday, June 14, 2010, 7:31 PM

On 06/14/2010 12:48 PM, Malcolm Parker-Lisberg wrote:
> An estimated 0.34 billion metric tons of copper currently exists in the ocean’s waters based on a concentration of 0.25 ug/L and a volume of 1.338 x 109 km3
>  From MadSci Network, Internet site,
> “www.madsci.org”
>
> That's a lot of printed circuit boads
>
>    

Copper is death to invertebrates in the ocean. Primarily, that means 
coral, shrimp, crabs, ... While your concentrations are correct as an 
average, close to the places where the effluent water (and I mean 
processed and safe as far as sewage is considered) will have higher 
concentrations.

The stuff really should be kept out of the ocean. Of course, if you live 
near Louisiana, Mississippi, Alabama or Florida right now, it probably 
doesn't reall matter all that much.

-- 
Our peculiar security is in the possession of a written Constitution.
Let us not make it a blank paper by construction."

    --Thomas Jefferson, letter to Wilson Nicholas, 1803

There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order.
  -- Ed Howdershelt (Author)



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

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






      

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

Each to their own and I'd never asign any morality factor in such a thing.

For me, a little Drano, a coffee filter and it won't wind up in the ocean :)

Hey, I'm just hoping I'll still want to take my trip to the Florida Keys 
next year :)

On 06/14/2010 02:01 PM, Malcolm Parker-Lisberg wrote:
>
> Copper chloride is produced in the sea and a high concentrations is\ufffd  indeed a roblem, at less than lethal concentrations it reduces growth. One published paper demonstrates how Krill have adapted to its presence and secrete it. It is high concentrations on an industrial scale that causes problems not low concentrations from litre quantaties.
>
> I don't suffer from insanity I enjoy it!
>
> --- On Mon, 6/14/10, Dale J. Chatham<dale@...>  wrote:
>
>
>    


-- 
Our peculiar security is in the possession of a written Constitution.
Let us not make it a blank paper by construction."

    --Thomas Jefferson, letter to Wilson Nicholas, 1803

There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order.
  -- Ed Howdershelt (Author)

>
> An estimated 0.34 billion metric tons of copper currently exists in the ocean’s waters based on a concentration of 0.25 ug/L and a volume of 1.338 x 109 km3
>

Hmmmm, a 1/3 billion metric tons of copper is in the oceans?  Does that take into account the 3 oz of etching solution I dumped this week?

Seriously - I do think this thread has went long enough on the impacts of dumping etching solutions - we've all made our points known, and now simply repeating.

I should not have commented, Let's have fun and etch some boards!!  

73 de Ken H.

>Anything with dissolved copper should not be dumped down the drain, at 
>least if you live in a coastal area like I do where the water eventually 
>ends up in the ocean. 

     The problem with the copper is more likely at the sewage treatment 
plant, for the same reasons that used photographic fixer (silver ions) is 
something they'd rather not have going down the drain. Those metal ions 
kill off the microorganisms (and not so micro) they use to digest the 
sewage. The tour through the hyperion in Huntington Beach many years ago 
was quite interesting.


     I've been waiting for someone else to point this out but haven't 
seen it yet, so...

*******
     DO NOT store HCl/H2O2 (hydrochloric/muriatic acid and hydrogen 
peroxide) etchant in sealed glass bottles. As the peroxide decomposes it 
produces oxygen gas and the resulting pressuure can cause the bottle to 
burst. The pressure can also cause an acid spray when you open it, not 
good for the eyes.
*******

     I like to use the brown plastic bottles that drugstore ~3% peroxide 
comes in, I don't fill them more than half full and I squeeze them before 
capping so there's plenty of room for expansion. Still, I've seen them 
bulge and show a line up the side where the pressure has stretched and 
nearly burst the bottle.

     Seems to me that the "40 Volume" on the higher concentration 
peroxide bottles means it will decompose to 40x it's liquid volume as 
gas. If that's correct, then one cubic inch (unit) will become 40 cubic 
inches (units) of gas while you're not looking.

     Leave plenty of room for expansion, store the bottle in another 
larger container, and just because it hasn't happened to you yet doesn't 
mean it won't happen twenty minutes from now.

     -Gary