Homebrew PCBs

Hi everyone,

I'm just getting started making PCBs. Actually, I've been trying for some time, but have only recently been able to get good results using the toner transfer method.

Currently I am following the instructions in this guide to make etchant from Hydrochloric Acid and Hydrogen Peroxide and I have been using this solution for my boards: http://www.instructables.com/id/Stop-using-Ferric-Chloride-etchant!--A-better-etc/

I have also considered using Ferric Chloride, as it is available from my local Radioshack (although it is a little expensive).

What is the best way to dispose of these etchants? Or perhaps I should ask, what is the cheapest way to safely dispose of these etchants ;-) I'm pretty sure there is a hazardous waste disposal center near me, but that it costs money to take stuff there. Is there any way I can dispose of this stuff at home?

Thanks a lot for your help!

"nathan_h_tna" <nathan_h_tna@...> writes:
> What is the best way to dispose of these etchants?

Don't dispose of them!  The acid/peroxide etchant becomes CuCl etchant
with use, which can be air regenerated and used over and over again.

The FeCl etchant can be rejeuvenated with a little Hydrochloric acid;
eventually it also becomes CuCl etchant.

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

From: "DJ Delorie" <dj@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Tuesday, January 05, 2010 5:33 AM
Subject: Re: [Homebrew_PCBs] How to dispose of etchant?


> 
> "nathan_h_tna" <nathan_h_tna@...> writes:
>> What is the best way to dispose of these etchants?
> 
> Don't dispose of them!  The acid/peroxide etchant becomes CuCl etchant
> with use, which can be air regenerated and used over and over again.
> 
> The FeCl etchant can be rejeuvenated with a little Hydrochloric acid;
> eventually it also becomes CuCl etchant.

+ H2O2, otherwise it will be cuprous chloride which doesn't etch.

Leon

On Jan 5, 2010, at 12:33 AM, DJ Delorie wrote:

>> What is the best way to dispose of these etchants?
>
> Don't dispose of them!  The acid/peroxide etchant becomes CuCl etchant
> with use, which can be air regenerated and used over and over again.

What if you really really need to? :-)  Baking soda?

--
Brian Lalor
blalor@...

Brian Lalor <blalor@...> writes:
> > Don't dispose of them!  The acid/peroxide etchant becomes CuCl etchant
> > with use, which can be air regenerated and used over and over again.
> 
> What if you really really need to? :-)  Baking soda?

IIRC you add a base (sodium hydroxide (drain cleaner) if you have it,
else baking soda) until the copper precipitates.  That tells you the
pH has just passed neutral.  Let the water evaporate, leaving a copper
salt "brick" at the bottom.  Bring that to a hazmat place.

"Leon Heller" <leon355@...> writes:
> > The FeCl etchant can be rejeuvenated with a little Hydrochloric acid;
> > eventually it also becomes CuCl etchant.
> 
> + H2O2, otherwise it will be cuprous chloride which doesn't etch.

What happens if you dump spent FeCl etchant into a CuCl ethant bath?

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

From: "DJ Delorie" <dj@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Tuesday, January 05, 2010 5:26 PM
Subject: Re: [Homebrew_PCBs] How to dispose of etchant?


> 
> "Leon Heller" <leon355@...> writes:
>> > The FeCl etchant can be rejeuvenated with a little Hydrochloric acid;
>> > eventually it also becomes CuCl etchant.
>> 
>> + H2O2, otherwise it will be cuprous chloride which doesn't etch.
> 
> What happens if you dump spent FeCl etchant into a CuCl ethant bath?

It'll work OK with oxygenation.

Leon

DJ Delorie wrote:

> 
> IIRC you add a base (sodium hydroxide (drain cleaner) if you have it,
> else baking soda) until the copper precipitates. That tells you the
> pH has just passed neutral. Let the water evaporate, leaving a copper
> salt "brick" at the bottom. Bring that to a hazmat place.
> 

Not really like that. I don't really know what chemistry things happens
for sure but i can say that (since dumbly i try it once with a bit of
used etchant) if you add NaOH until the thing starts to warm and get hot
(or warm it by other means), after it cool and settle down you will end
with a black fine powder mud at bottom that should be the complex
Cu(FeO(OH)2)2 thing, above it a block of crystal NaCl in about the same
amount of added NaOH, and all the remaining up top is clean transparent
water. But it end even worst for disposal (etchant plus NaOH). SO DONT
DO IT!! 
There is no away i know to precipitate the copper on Cl based etchants.
But i guess in my ignorance that FeCl3 etchants should be possible to
expensively recover copper like CuCl with those DuPont ion membrane,
large platinum anodes and ~1000A psu like some big pcb shops seem to do,
ending with HCl and copper bars IIRC. 

Anyway nobody should use Ferric Chloride etchant this days, is a mess,
non recoverable, not simple to disposal (pollutant if you dump it),
expensive, and in 2010 you have plenty alternatives available like
Cupric Chloride.

Simao Cardoso wrote:
> DJ Delorie wrote:
> 
>> IIRC you add a base (sodium hydroxide (drain cleaner) if you have it,
>> else baking soda) until the copper precipitates. That tells you the
>> pH has just passed neutral. Let the water evaporate, leaving a copper
>> salt "brick" at the bottom. Bring that to a hazmat place.
>>
> 
> Not really like that. I don't really know what chemistry things happens
> for sure but i can say that (since dumbly i try it once with a bit of
> used etchant) if you add NaOH until the thing starts to warm and get hot
> (or warm it by other means), after it cool and settle down you will end
> with a black fine powder mud at bottom that should be the complex
> Cu(FeO(OH)2)2 thing, above it a block of crystal NaCl in about the same
> amount of added NaOH, and all the remaining up top is clean transparent
> water. But it end even worst for disposal (etchant plus NaOH). SO DONT
> DO IT!! 
> There is no away i know to precipitate the copper on Cl based etchants.
> But i guess in my ignorance that FeCl3 etchants should be possible to
> expensively recover copper like CuCl with those DuPont ion membrane,
> large platinum anodes and ~1000A psu like some big pcb shops seem to do,
> ending with HCl and copper bars IIRC. 
> 
> Anyway nobody should use Ferric Chloride etchant this days,

I will use nothing else.

 > is a mess,

I haven't made a mess since using it the last 50+ times

> non recoverable,

It lasts forever. Just cover the container. Add a bit of HCl
every few months.

> not simple to disposal (pollutant if you dump it),

It's an excellent weed killer. There's rarely a reason to dispose
of it, so it's more enviroweenie friendly than most others.

> expensive, and in 2010 you have plenty alternatives available like
> Cupric Chloride.

Only expensive in retail shops. Buy it in bulk as "Profloc F" for $2/Lt.
Once you have a tank set up, there's little reason to buy much more.

Profloc F is a sewer treatment floculating agent iirc.
I got 30Lt of the stuff. Anyone in the local electronics clubs can
get it from me cheap.

I just love reading these etchent points being argued back and forth
when all i can buy is fecl, and even then its expensive, as in the UK
all we have left where I am is 'maplins' - a uk company that was the
best of the 1980's electronic components suppliers, now it thinks its
a cross between the disney store full of toys and radio-shack as we
knew it as tandy.

http://www.maplin.co.uk

update: OMG they dont do fecl! its sodium persulphate now, must buy
some and try it.

Lez wrote:
> I just love reading these etchent points being argued back and forth
> when all i can buy is fecl, and even then its expensive, as in the UK
> all we have left where I am is 'maplins' - a uk company that was the
> best of the 1980's electronic components suppliers, now it thinks its
> a cross between the disney store full of toys and radio-shack as we
> knew it as tandy.
> 
> http://www.maplin.co.uk
> 
> update: OMG they dont do fecl! its sodium persulphate now, must buy
> some and try it.

They stand to profit from that better because you're forced to dispose
of it due to decomposition. Real "envirofriendly" with all that copper
in it. With my FeCl, it is holding all the copper i've etched in the
same tank for 2 years. It would be good to make the sodium persulphate
stuff convert to a long lasting CuCl etchant. I haven't tried that.

Lez <lez.briddon@...> writes:
> as in the UK all we have left where I am is 'maplins'

I built my CuCl tank using stuff from the local supermarket (hydrogen
peroxide 3% - for cleaning cuts) and hardware store (muriatic acid 37%
- for cleaning concrete).  It's not specialty stuff.

If I don't dispose of the acid/peroxide solution after just one use, how should I store it? Should I be concerned about storing it in my basement?

You should store it in a covered container, but with a small pressure
relief opening. Like a small hole, perhaps even covered with a piece
of foam rubber to cut down air exchange but let out any pressure.

The H2O2 will continue to decompose, producing oxygen, which can build
up pressure and rupture a container if it can't escape.

Keeping air exchange to a minimum is in your interest because you
don't want HCL fumes in your basement, and you don't want the etchant
to dry out crystallizing the CUCl (although the long green crystals
are quite beautiful).

Another option is to leave it in the etching tank, if you can cover it
with a lid and safely store it somewhere where it can't be tipped over
or accidentally gotten to by children, pets, etc..

Generally speaking glass is better than plastic, I've seen HCl damage
plastics in the long run and small amounts will evaporate through the
material, causing rust on nearby steel parts. This is more of a
problem with bottles of HCl rather than the etchant (where it is
diluted).

Whatever you do, it is highly recommended to put your etchant
container inside a larger vessel that can catch a spill. It is always
possible for a container to break.

ST

On Wed, Jan 6, 2010 at 5:32 PM, nathan_h_tna <nathan_h_tna@...> wrote:
> If I don't dispose of the acid/peroxide solution after just one use, how should I store it? Should I be concerned about storing it in my basement?
>

Russell Shaw wrote:

> 
> I will use nothing else.
> I haven't made a mess since using it the last 50+ times
> It lasts forever. Just cover the container. Add a bit of HCl
> every few months.
> It's an excellent weed killer. There's rarely a reason to dispose
> of it, so it's more enviroweenie friendly than most others.
> Only expensive in retail shops. Buy it in bulk as "Profloc F" for
> $2/Lt.
> Once you have a tank set up, there's little reason to buy much more.
> 
> Profloc F is a sewer treatment floculating agent iirc.
> I got 30Lt of the stuff. Anyone in the local electronics clubs can
> get it from me cheap.


I should know already to not step on the long experience off so much of
you in here. You use it better than i did, or most people do. My comment
intention was to point the younger people who in my view should be
buying muriatic acid, peroxide, food container, air pump instead Ferric
Chloride. And where i live all those things can be bought in one place
only and at same price of 1Kg Ferric Chloride in a electronics supply
store. 

Not as homebrew, but in a moment of my short life, i also did use more
than 100L of it in 40%, in a spray machine. And although in theory FeCl3
can old much more copper in solution than other etchants, the etch
quality decrease really fast with copper content. The etchant choice or
setup wasn't my call, companies like megauk and bungard say to schools,
universities and small dumb board houses that FeCl3 is the best thing
around since they earn big money selling it over and over again. And
these people simple buy it locally and stay ignorant happy about
etchants. While they could be using CuCl auto regenerated in the spray
chamber, given better stable results along etchant usage, cheaper and
even easier to get. 
Unfortunately the first thing i read about CuCl was that it was used in
the early 60's. Got from copper mines, used as etchant and returned to
copper mines without regeneration, by the transport price only, before
copper mines changed to sulfuric electrowining. This should be super
wrong but keep me away from using it earlier. 

So instead of saying 'X is better' we should present 2 or 3 options to
everyone always, don't you agree?

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

  From: Simao Cardoso 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Wednesday, January 06, 2010 9:37 PM
  Subject: Re: [Homebrew_PCBs] How to dispose of etchant?


    
  Russell Shaw wrote:

  > 
  > I will use nothing else.

  <snip>

  I should know already to not step on the long experience off so much of
  you in here. You use it better than i did, or most people do. My comment
  intention was to point the younger people who in my view should be
  buying muriatic acid, peroxide, food container, air pump instead Ferric
  Chloride. And where i live all those things can be bought in one place
  only and at same price of 1Kg Ferric Chloride in a electronics supply
  store. 

  Not as homebrew, but in a moment of my short life, i also did use more
  than 100L of it in 40%, in a spray machine. And although in theory 

  <snip>

  So instead of saying 'X is better' we should present 2 or 3 options to
  everyone always, don't you agree?



  
  Simao,
  I agree with you.  I know some people feel very strong about what they use
  and that is fine with me.   I have been making boards since about 1963 and 
  have a spray etcher but do not use it now.  I still make around 30 boards a month 
  and use nothing but muriatic acid and peroxide Even tho I have a 5 gallon bucket
  of Ferric Chloride  that I do not use.
   So I say to, each his own.
  Derward Myrick  PE  KD5WWI

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

Are the fumes flammable? Unfortunately I would have to store this in my basement, about 20ft away from my gas furnace and bedroom..

Not flammable as such, decomposing H2O2 produces oxygen of course,
which strongly accelerates combustion.

I'd not be worried, the quantities are low and the release is fairly slow rate.

ST

On Sun, Jan 10, 2010 at 8:54 PM, nathan_h_tna <nathan_h_tna@...> wrote:
> Are the fumes flammable? Unfortunately I would have to store this in my basement, about 20ft away from my gas furnace and bedroom..
>

All you nned to know http://www.sciencelab.com/xMSDS-Ferric_Chloride_TS-9925886

Basically search for "MSDS ferric chloride"

As for disposal, use household hasardous waste disposal times in your community.  Mark the chemicals.  Don't have a lot.

--- On Sun, 1/10/10, Stefan Trethan <stefan_trethan@...> wrote:

From: Stefan Trethan <stefan_trethan@...>
Subject: Re: [Homebrew_PCBs] Re: How to dispose of etchant?
To: Homebrew_PCBs@yahoogroups.com
Date: Sunday, January 10, 2010, 3:05 PM







 



  


    
      
      
      Not flammable as such, decomposing H2O2 produces oxygen of course,

which strongly accelerates combustion.



I'd not be worried, the quantities are low and the release is fairly slow rate.



ST



On Sun, Jan 10, 2010 at 8:54 PM, nathan_h_tna <nathan_h_tna@ yahoo.com> wrote:

> Are the fumes flammable? Unfortunately I would have to store this in my basement, about 20ft away from my gas furnace and bedroom..

>



    
     

    
    


 



  






      

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

That link's for Ferric Chloride, though, isn't it? I'd like to keep using the acid/peroxide solution if possible as it's cheaper (and because I already have it!).

In article <c3241b81001051616g6c7523f2yafd60edfddf72b45@...>,
   Lez <lez.briddon@...> wrote:
> I just love reading these etchent points being argued back and forth
> when all i can buy is fecl, and even then its expensive, as in the UK
> all we have left where I am is 'maplins' - a uk company that was the
> best of the 1980's electronic components suppliers, now it thinks its
> a cross between the disney store full of toys and radio-shack as we
> knew it as tandy.

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

Maplin were always crap.

> update: OMG they dont do fecl! its sodium persulphate now, must buy
> some and try it.

Perhaps you need introducing to http://www.cpc.co.uk

OK it's mail order but 500g Ferric Chloride pellets will cost you 5.77
quid + p&p.

If you wander round their, other sections, capacitors (1609), resistors
(900), semiconductors (3682) and many other and can make your order 45
quid, p&p is free.

http://www.cricklewoodelectronics.com are also very good especially for
older semiconductors.

http://www.megauk.com will also supply just about anything you need for
making PCBs.

There are a number of others.

-- 
Stuart
http://www.torrens.org.uk/ZFC/gallery/winsor.html

Thanks for helping me understand what precautions I need to take when using this stuff.

From what I've read, it looks like mixing the hydrochloric acid (hydrogen chloride (HCL) in water) with peroxide (H2O2) and then putting copper in it produces cucl2, which eventually becomes cucl (which doesn't eat copper?), and that's why peroxide needs to keep being added – to regenerate the oxygen and make it cucl2 again. Is that basically correct?

This chemical reaction produces chlorine gas which is not explosive – so I guess I don't need to be worried about the nearby gas furnace (if that should have even been a concern in the first place) – but is apparently not good to breathe. Exactly how bad is it to breathe this stuff, though? I've read several places that repeated exposure could cause serious health conditions.. Should I buy a respirator to filter out the chlorine fumes? (Remember, I'm using this in my basement which doesn't have very good ventilation).

What type of protective equipment should be worn?

What should I do if I spill some of this (or a lot of it) on the workbench or floor, or on myself for that matter?

Concerning the storage of the etchant, it seems like the two possibilities are using a glass container or a plastic container. Some people have said that plastic containers will fail eventually, but the problem with a glass container is that if it gets dropped it will break. What type of container would you recommend I store this in?

One last thing is that the MSDS sheet for Hydrochloric acid says, "Forms flammable hydrogen gas on contact with metals." Does what we're doing form hydrogen gas? Because that IS explosive..

So, to recap:

1)	How bad is breathing the chlorine gas? (e.g. should I purchase a respirator?).
2)	What protective equipment should I wear?
3)	What should I do if I spill it?
4)	How should I store it?
5)	Should be I worried about the hydrogen byproduct?

Thank so much!

On Mon, 15 Mar 2010, nathan_h_tna wrote:

> So, to recap:
>
> 1)	How bad is breathing the chlorine gas? (e.g. should I purchase a 
> respirator?).
> 2)	What protective equipment should I wear?
> 3)	What should I do if I spill it?
> 4)	How should I store it?
> 5)	Should be I worried about the hydrogen byproduct?

I don't know if a respirator would be any good.  Chlorine is also harms 
the eyes.  It was used as a weapon in WW1.  Dissolving stuff in HCl is 
fume-hood work.

-- 
David Griffith
dgriffi@...

A: Because it fouls the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing in e-mail?

--- On Mon, 3/15/10, nathan_h_tna <nathan_h_tna@...> wrote:

> 1)    How bad is breathing the chlorine gas?
> (e.g. should I purchase a respirator?).

submarine's crew is absolutely forbidden to wash their clothes with bleach no matter how rinse...
does this give you a hint?

A poorly ventilated basement is the absolute worst place I can think of to produce chlorine gas.  Chlorine is significantly denser than air, meaning that it will tend to settle to the lowest place available, and will slowly displace the air there.  Over time, you would be turning your basement into a gas chamber.


________________________________
> To: Homebrew_PCBs@yahoogroups.com
> From: nathan_h_tna@...
> Date: Mon, 15 Mar 2010 17:05:11 +0000
> Subject: [Homebrew_PCBs] Re: How to dispose of etchant?
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
> Thanks for helping me understand what precautions I need to take when using this stuff.
>
>
>
> From what I've read, it looks like mixing the hydrochloric acid (hydrogen chloride (HCL) in water) with peroxide (H2O2) and then putting copper in it produces cucl2, which eventually becomes cucl (which doesn't eat copper?), and that's why peroxide needs to keep being added – to regenerate the oxygen and make it cucl2 again. Is that basically correct?
>
>
>
> This chemical reaction produces chlorine gas which is not explosive – so I guess I don't need to be worried about the nearby gas furnace (if that should have even been a concern in the first place) – but is apparently not good to breathe. Exactly how bad is it to breathe this stuff, though? I've read several places that repeated exposure could cause serious health conditions.. Should I buy a respirator to filter out the chlorine fumes? (Remember, I'm using this in my basement which doesn't have very good ventilation).
>
>
>
> What type of protective equipment should be worn?
>
>
>
> What should I do if I spill some of this (or a lot of it) on the workbench or floor, or on myself for that matter?
>
>
>
> Concerning the storage of the etchant, it seems like the two possibilities are using a glass container or a plastic container. Some people have said that plastic containers will fail eventually, but the problem with a glass container is that if it gets dropped it will break. What type of container would you recommend I store this in?
>
>
>
> One last thing is that the MSDS sheet for Hydrochloric acid says, "Forms flammable hydrogen gas on contact with metals." Does what we're doing form hydrogen gas? Because that IS explosive..
>
>
>
> So, to recap:
>
>
>
> 1) How bad is breathing the chlorine gas? (e.g. should I purchase a respirator?).
>
> 2) What protective equipment should I wear?
>
> 3) What should I do if I spill it?
>
> 4) How should I store it?
>
> 5) Should be I worried about the hydrogen byproduct?
>
>
>
> Thank so much!
>
>
>
>
>
>
>
>
>
> 
>
>
>
>
>
>
> 		 	   		  
_________________________________________________________________
Hotmail: Trusted email with Microsoft’s powerful SPAM protection.
http://clk.atdmt.com/GBL/go/210850552/direct/01/

--- In Homebrew_PCBs@yahoogroups.com, "Herbert E. Plett" <cachureos@...> wrote:
>
> 
> 
> --- On Mon, 3/15/10, nathan_h_tna <nathan_h_tna@...> wrote:
> 
> > 1)    How bad is breathing the chlorine gas?
> > (e.g. should I purchase a respirator?).
> 
> submarine's crew is absolutely forbidden to wash their clothes with bleach no matter how rinse...
> does this give you a hint?
>


With the stagnant air in a submarine any crud in the air could be a problem. Chlorine is not too bad in small amounts, it's used as a sanitizer in swimming pools afterall.

Chlorine Gas is poisonous  it will kill you. :(

It will eat the paint off your car and turn it into rust.

It will do the same to your lungs!.

It was used in WWI, along with mustard gas and others, to kill troops

Don't F**k with it.
Use of a respirator is mandatory!
Get a good one, don't go cheap.

Where I work we use a lot of Chemicals, including chlorine.
I had to go thru HAZ MAT training, so I know a little about it.
BE SAFE!


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

The air in a submarine is hardly stagnet. It is constantly recirculated scrubbed and monitored. Chlorine bleach is forbidden due to the chlorine gas detectors. The submarines battery acid and sea water produce chlorine gas which is a very bad thing in a sealed enviroment. 

Roger

--- In Homebrew_PCBs@yahoogroups.com, "James" <jamesrsweet@...> wrote:

>
> 
> 
> --- In Homebrew_PCBs@yahoogroups.com, "Herbert E. Plett" <cachureos@> wrote:
> >
> > 
> > 
> > --- On Mon, 3/15/10, nathan_h_tna <nathan_h_tna@> wrote:
> > 
> > > 1)    How bad is breathing the chlorine gas?
> > > (e.g. should I purchase a respirator?).
> > 
> > submarine's crew is absolutely forbidden to wash their clothes with bleach no matter how rinse...
> > does this give you a hint?
> >
> 
> 
> With the stagnant air in a submarine any crud in the air could be a problem. Chlorine is not too bad in small amounts, it's used as a sanitizer in swimming pools afterall.
>

I can't remember if you addressed the possibility of using the etchant outside -- since I'm still at the stage of mixing up HCl and H2O2 to make etchant, I mix it up outside and etch outside. I've done this in weather down to around 32 degrees F -- etches a little slower in the cold, but still works. I store my HCl and used etchant (waiting to be turned into CuCl) outside as well -- I have a gallon jug of HCl and about 1.5 liters of used etchant; I store both inside a 5 gallon plastic bucket with a lid on. So far (about 8 months) it seems to be working fine.

When I get enough used etchant saved up, I expect I'll make a bubble tank to regenerate to CuCl. I'm not sure what I'll do for storage at that point. But since I only do an occasional board here or there, it may be a while yet before I need to figure it out. :)

--- In Homebrew_PCBs@yahoogroups.com, "nathan_h_tna" <nathan_h_tna@...> wrote:

>
> Thanks for helping me understand what precautions I need to take when using this stuff.
> 
> From what I've read, it looks like mixing the hydrochloric acid (hydrogen chloride (HCL) in water) with peroxide (H2O2) and then putting copper in it produces cucl2, which eventually becomes cucl (which doesn't eat copper?), and that's why peroxide needs to keep being added – to regenerate the oxygen and make it cucl2 again. Is that basically correct?
> 
> This chemical reaction produces chlorine gas which is not explosive – so I guess I don't need to be worried about the nearby gas furnace (if that should have even been a concern in the first place) – but is apparently not good to breathe. Exactly how bad is it to breathe this stuff, though? I've read several places that repeated exposure could cause serious health conditions.. Should I buy a respirator to filter out the chlorine fumes? (Remember, I'm using this in my basement which doesn't have very good ventilation).
> 
> What type of protective equipment should be worn?
> 
> What should I do if I spill some of this (or a lot of it) on the workbench or floor, or on myself for that matter?
> 
> Concerning the storage of the etchant, it seems like the two possibilities are using a glass container or a plastic container. Some people have said that plastic containers will fail eventually, but the problem with a glass container is that if it gets dropped it will break. What type of container would you recommend I store this in?
> 
> One last thing is that the MSDS sheet for Hydrochloric acid says, "Forms flammable hydrogen gas on contact with metals." Does what we're doing form hydrogen gas? Because that IS explosive..
> 
> So, to recap:
> 
> 1)	How bad is breathing the chlorine gas? (e.g. should I purchase a respirator?).
> 2)	What protective equipment should I wear?
> 3)	What should I do if I spill it?
> 4)	How should I store it?
> 5)	Should be I worried about the hydrogen byproduct?
> 
> Thank so much!
>

--- In Homebrew_PCBs@yahoogroups.com, Rocko <sunblaster5@...> wrote:
>
> Chlorine Gas is poisonous  it will kill you. :(
> 
> It will eat the paint off your car and turn it into rust.
> 
> It will do the same to your lungs!.
> 
> It was used in WWI, along with mustard gas and others, to kill troops
> 
> Don't F**k with it.
> Use of a respirator is mandatory!
> Get a good one, don't go cheap.
> 
> Where I work we use a lot of Chemicals, including chlorine.
> I had to go thru HAZ MAT training, so I know a little about it.
> BE SAFE!
> 
> 
> [Non-text portions of this message have been removed]
>


So is Ozone, and Bromine, and Hydrogen Sulfide, and many other common substances. Yes in large amounts they all can kill you. In smaller amounts they can cause irritation to eyes, skin, and mucus membranes. In still smaller amounts they are pretty safe. Swimming pools and hot tubs use the first three as sanitizers, those air ionizer things produce small (and sometimes dangerously large) amounts of ozone. Hydrogen Sulfide or "rotten egg gas" is in farts, it's ok, just use common sense and have ventilation so it doesn't build up. With the quantities one is likely to be using at home it's not a big deal. Don't expose yourself unnecessarily, but one does not need to go overboard. If in doubt, do it outside.

> 
> When I get enough used etchant saved up, I expect I'll make a bubble tank to regenerate to CuCl. I'm not sure what I'll do for storage at that point. But since I only do an occasional board here or there, it may be a while yet before I need to figure it out. :)
> 



I use a small vertical tank I made out of solvent welded 3/16" plexiglass with an aquarium heater on one side and a plastic tube with a row of tiny holes connected to an aquarium air pump as a bubbler. It holds about 2 quarts of etchant max and is good for up to about 6"x8" PCB. 

The used etchant is currently stored in a clearly labeled plastic bottle that formerly held cleaning liquid but I'm gonna order a proper chemical bottle for it. I keep it in the garage in a plastic bag that has some baking soda in it just in case acid leaks. It was a small amount so I mixed it in the kitchen with the exhaust fan on, and I normally etch in the bathroom with the fan in there running. Once weather warms up I'll switch to doing it outside, but I haven't had problems with fumes.  

Definitely wear gloves and safety glasses or goggles when working with this stuff, if you drop something and it splashes on your skin or in your eyes it will not feel good.