Homebrew PCBs

Hi all

I am etching with Muriatic Acid and Hydrogen Peroxide, so far I am happy with the speed and quality of the etch but I am concerned with the fumes. It's ok to etch the boards outside this time of year in the north east but I will have to work in a closed garage in the winter. What can I do the limit or eliminate the fumes from the process?

AP

If you plan on making many PCB's, then I would suggest building a small fume hood that your etching tank will reside in. Use an exhaust fan whose flow rate(cfm) is 10 times the volume of the fume hood, and duct the exhaust outside. The nice thing about having a fume hood, is that it will allow you to experiment with different chemistries. 

Be safe and have fun!

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

>
> Hi all
> 
> I am etching with Muriatic Acid and Hydrogen Peroxide, so far I am happy with the speed and quality of the etch but I am concerned with the fumes. It's ok to etch the boards outside this time of year in the north east but I will have to work in a closed garage in the winter. What can I do the limit or eliminate the fumes from the process?
> 
> AP
>

How much of the fumes can humans tolerate? Are the fumes harmful? Do 
they damage other stuff they come in contact with? Is it OK to put a lid 
on the plastic etching pan so as to be able to agitate it without risk 
of spilling the etchant?

Steve K8JQ

Daniel Howard Bryant wrote:
> If you plan on making many PCB's, then I would suggest building a small fume hood that your etching tank will reside in. Use an exhaust fan whose flow rate(cfm) is 10 times the volume of the fume hood, and duct the exhaust outside. The nice thing about having a fume hood, is that it will allow you to experiment with different chemistries. 
>
> Be safe and have fun!
>
> --- In Homebrew_PCBs@yahoogroups.com, "perri.anthony" <perri.anthony@...> wrote:
>   
>> Hi all
>>
>> I am etching with Muriatic Acid and Hydrogen Peroxide, so far I am happy with the speed and quality of the etch but I am concerned with the fumes. It's ok to etch the boards outside this time of year in the north east but I will have to work in a closed garage in the winter. What can I do the limit or eliminate the fumes from the process?
>>
>> AP
>>
>>     
>
>
>
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>
>
>   

-- 
Read The Patriot   It's Right -- It's Free
http://PatriotPost.US/subscribe/ Veritas vos Liberabit

The fumes can be reduced a lot by going to CuCl from your HCl H2O2
setup. A lid helps too.

I operate a CuCl etcher in a mechanical shop area with tools and steel
around, and no corrosion. The tank is covered but not airtight.

I did however rust a set of drills next to a container of HCL and H2O2
with much too high HCl concentration, so some care is advised.

An airtight lid should not be used on this etchant, since the H2O2
needs a release or the container may burst.

ST

On Mon, Jun 8, 2009 at 5:10 AM, Steve<steve65@...> wrote:
> How much of the fumes can humans tolerate? Are the fumes harmful? Do
> they damage other stuff they come in contact with? Is it OK to put a lid
> on the plastic etching pan so as to be able to agitate it without risk
> of spilling the etchant?
>
> Steve K8JQ
>

Steve <steve65@...> writes:
> How much of the fumes can humans tolerate? Are the fumes harmful?

Chlorine gas is toxic.  I don't know the LD50 but I don't want to find
out the hard way either.  I've got a fume hood and vent, just a simple
bathroom vent fan and some flexible aluminum foil ductwork.

Copper salts are toxic if ingested, so don't drink your etchant either ;-)

Hello

Intersting etching chemicals.... can you tell me what is the proportion between Muriatic Acid and Hydrogen Peroxid.

Than you




________________________________

From: Daniel Howard Bryant <coloradobryant@...>
To: Homebrew_PCBs@yahoogroups.com
Sent: Sunday, June 7, 2009 10:03:01 PM
Subject: [Homebrew_PCBs] Re: Muriatic Acid and Hydrogen Peroxide Fumes





If you plan on making many PCB's, then I would suggest building a small fume hood that your etching tank will reside in. Use an exhaust fan whose flow rate(cfm) is 10 times the volume of the fume hood, and duct the exhaust outside. The nice thing about having a fume hood, is that it will allow you to experiment with different chemistries. 

Be safe and have fun!

--- In Homebrew_PCBs@ yahoogroups. com, "perri.anthony" <perri.anthony@ ...> wrote:
>
> Hi all
> 
> I am etching with Muriatic Acid and Hydrogen Peroxide, so far I am happy with the speed and quality of the etch but I am concerned with the fumes. It's ok to etch the boards outside this time of year in the north east but I will have to work in a closed garage in the winter. What can I do the limit or eliminate the fumes from the process?
> 
> AP
>





      

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

--- In Homebrew_PCBs@yahoogroups.com, DJ Delorie <dj@...> wrote:
>
> 
> Steve <steve65@...> writes:
> > How much of the fumes can humans tolerate? Are the fumes harmful?
> 
> Chlorine gas is toxic.  I don't know the LD50 but I don't want to find
> out the hard way either.  I've got a fume hood and vent, just a simple
> bathroom vent fan and some flexible aluminum foil ductwork.
> 
> Copper salts are toxic if ingested, so don't drink your etchant either ;-)
>

Thanks for the comments. 

Can I get some ideas on how to build this hood? Using a bathroom vent fan sounds like a good idea but aren't the fan blades made of metal? And wouldn’t that corrode in a short period of time with this chemical mixture?

I am using a 2:1 ratio of Hydrogen Peroxide to Muriatic Acid.

AP

--- In Homebrew_PCBs@yahoogroups.com, Andres Hernandez <afhernandez79@...> wrote:

>
> Hello
> 
> Intersting etching chemicals.... can you tell me what is the proportion between Muriatic Acid and Hydrogen Peroxid.
> 
> Than you
> 
> 
> 
> 
> ________________________________
> From: Daniel Howard Bryant <coloradobryant@...>
> To: Homebrew_PCBs@yahoogroups.com
> Sent: Sunday, June 7, 2009 10:03:01 PM
> Subject: [Homebrew_PCBs] Re: Muriatic Acid and Hydrogen Peroxide Fumes
> 
> 
> 
> 
> 
> If you plan on making many PCB's, then I would suggest building a small fume hood that your etching tank will reside in. Use an exhaust fan whose flow rate(cfm) is 10 times the volume of the fume hood, and duct the exhaust outside. The nice thing about having a fume hood, is that it will allow you to experiment with different chemistries. 
> 
> Be safe and have fun!
> 
> --- In Homebrew_PCBs@ yahoogroups. com, "perri.anthony" <perri.anthony@ ...> wrote:
> >
> > Hi all
> > 
> > I am etching with Muriatic Acid and Hydrogen Peroxide, so far I am happy with the speed and quality of the etch but I am concerned with the fumes. It's ok to etch the boards outside this time of year in the north east but I will have to work in a closed garage in the winter. What can I do the limit or eliminate the fumes from the process?
> > 
> > AP
> >
> 
> 
> 
> 
> 
>       
> 
> [Non-text portions of this message have been removed]
>

Andres Hernandez <afhernandez79@...> writes:
> Intersting etching chemicals.... can you tell me what is the
> proportion between Muriatic Acid and Hydrogen Peroxide.

It depends on the grade of peroxide.  If you're using common 3%
drugstore grade, it's "add one part acid to two parts peroxide".  For
stronger peroxide grades, you have to dilute the peroxide first.

Note that the HCl+H2O2 etchant turns into CuCl etchant with use, so no
need to discard it.  See:

http://members.optusnet.com.au/~eseychell/PCB/etching_CuCl/
http://www.instructables.com/id/Stop-using-Ferric-Chloride-etchant!--A-better-etc/

"perri.anthony" <perri.anthony@...> writes:
> Can I get some ideas on how to build this hood? Using a bathroom
> vent fan sounds like a good idea but aren't the fan blades made of
> metal? And wouldn't that corrode in a short period of time with this
> chemical mixture?

The one I got has a plastic fan.  As long as the fan is always running
while you've got the containers open, the fumes should be dilute
enough to be relatively harmless to the vent.  Here's an old photo of
my setup:

http://www.delorie.com/pcb/lab/img_0213.html

Ive been EXTREMELY careful of fumes using this method and am going to CuCL exclusively. FCL is just too poisonous to the environment (imho it should be outlawed). The reason im so cautious with this is ive played with 90% nitric and copper and breathed in the fumes and it was bad. Sickness, nausea and i could tell acidic fumes had done damage to my lungs and airway. That is from a good breath or two of the stuff, no more. I dont know the specifics but i bet the gaseous byproducts are similar or identical. I wouldnt etch indoors using this process period without some kind of fume control (your kitchen stove hood might work but i dont want to think about the effect).

Btw you think watching a fast etch is cool you should see what high grade nitric does to copper (and that is without an oxygen source).

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

From: "Charles" <lancedulak@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Sunday, June 28, 2009 6:00 PM
Subject: [Homebrew_PCBs] Re: Muriatic Acid and Hydrogen Peroxide Fumes


> Ive been EXTREMELY careful of fumes using this method and am going to CuCL 
> exclusively. FCL is just too poisonous to the environment (imho it should 
> be outlawed). The reason im so cautious with this is ive played with 90% 
> nitric and copper and breathed in the fumes and it was bad. Sickness, 
> nausea and i could tell acidic fumes had done damage to my lungs and 
> airway. That is from a good breath or two of the stuff, no more. I dont 
> know the specifics but i bet the gaseous byproducts are similar or 
> identical. I wouldnt etch indoors using this process period without some 
> kind of fume control (your kitchen stove hood might work but i dont want 
> to think about the effect).
>
> Btw you think watching a fast etch is cool you should see what high grade 
> nitric does to copper (and that is without an oxygen source).

FeCl3 isn't hazardous to the environment, it's actually used by water 
companies in their treatment plants! Copper can cause problems in effluent 
as it kills the bacteria that break down sewage, but the amount that gets 
flushed away when etching PCBs is negligible compared to the copper that is 
leached from copper pipework in the home.

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

FeCl is not really a problem for the environment. In fact it is
sometimes used for wastewater treatment.
Now dissolved copper is another issue.

ST

On Sun, Jun 28, 2009 at 7:00 PM, Charles<lancedulak@...> wrote:
> Ive been EXTREMELY careful of fumes using this method and am going to CuCL exclusively. FCL is just too poisonous to the environment (imho it should be outlawed). The reason im so cautious with this is ive played with 90% nitric and copper and breathed in the fumes and it was bad. Sickness, nausea and i could tell acidic fumes had done damage to my lungs and airway. That is from a good breath or two of the stuff, no more. I dont know the specifics but i bet the gaseous byproducts are similar or identical. I wouldnt etch indoors using this process period without some kind of fume control (your kitchen stove hood might work but i dont want to think about the effect).
>

On Sun, 2009-06-28 at 17:00 +0000, Charles wrote:
> FCL is just too poisonous to the environment (imho it should be
> outlawed).

Repeating what others said, the pollutant is copper, and FeCl3 can hold
a big quantity of it. Since it has no regeneration people will drain it
with copper and that's the bad thing.
FeCl3 is used in water treatment facilities ( i think to remove metallic
ions from water by filtration or deposition) . I know a small boardhouse
that still stupidly uses it because can be bought at the local water
treatment facility. And they send the waste FeCl3 with all the copper to
incineration!

>  The reason im so cautious with this is ive played with 90% nitric and
> copper and breathed in the fumes and it was bad. Sickness, nausea and
> i could tell acidic fumes had done damage to my lungs and airway. That
> is from a good breath or two of the stuff, no more. I dont know the
> specifics but i bet the gaseous byproducts are similar or identical.

> Btw you think watching a fast etch is cool you should see what high
> grade nitric does to copper (and that is without an oxygen source).
> 

Nitric acid is an Oxidizing. The gas produced in the copper reaction is 
nitric oxide which is toxic. People shouldn't use it as copper etch has
already discussed here long time ago by Adam Seychell, its hazard toxic
and air pollutant. 
But in my quest for metallic resist compatible etchants i found one
using nitric acid which i experimented. It's basically the same stuff as
peroxide-sulfuric etchant, but using nitric acid as the oxidizer. Since
i can't find here hydrogen peroxide in more than 9% solution, but i get
nitric acid in 60% at less 1.70eur/liter, it seem a cheap etch with easy
copper electrowinnig has i wanted. In peroxide-sulfuric the solution
amount is always increasing, so you always need some disposal. But with
nitric acid it consumes water, and the mixture of nitric sulfuric can
regenerate one HNO3 molecule in each 3 spent while makes CuSO4, besides
the air pollutant nitric oxide seems a nice etchant. I made various
tests but, the nitric acid attacks the toner almost completely... I also
etch a copper piece an got an enormous amount of CuS04 freezing it. The
solution turn almost clear, so almost all copper is easily deposited.
Only now i found a source of pure tin (in Australia) and i still have to
try the phosphorous mixture with plated tin as resist.

What have you used as resist in the nitric etchant?

> Ive been EXTREMELY careful of fumes using this method and am going to
> CuCL exclusively. 

I also have bad stories with having CuCl etchant and HCl on the self on
the same room as hundred of tools and an CNC router 'in construction'.
Lets say you need to have very careful with your containers and
phosphoric acid can give a nice look again to your tools but can't give
back the polish of expensive  CNC parts. Ventilation and sealed
containers are mandatory. 


>

FeCL3 is not poisonous, it is used in water purification station as a flocculator agent.

Mike.

--- On Sun, 6/28/09, Charles <lancedulak@...> wrote:

From: Charles <lancedulak@...>
Subject: [Homebrew_PCBs] Re: Muriatic Acid and Hydrogen Peroxide Fumes
To: Homebrew_PCBs@yahoogroups.com
Date: Sunday, June 28, 2009, 5:00 PM











    
            
            


      
      Ive been EXTREMELY careful of fumes using this method and am going to CuCL exclusively. FCL is just too poisonous to the environment (imho it should be outlawed). The reason im so cautious with this is ive played with 90% nitric and copper and breathed in the fumes and it was bad. Sickness, nausea and i could tell acidic fumes had done damage to my lungs and airway. That is from a good breath or two of the stuff, no more. I dont know the specifics but i bet the gaseous byproducts are similar or identical. I wouldnt etch indoors using this process period without some kind of fume control (your kitchen stove hood might work but i dont want to think about the effect).



Btw you think watching a fast etch is cool you should see what high grade nitric does to copper (and that is without an oxygen source).




 

      

    
    
	
	 
	
	








	


	
	


      

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

sorry, didn't see someone already answered to FeCl3 toxicity....

--- On Sun, 6/28/09, leon Heller <leon355@...> wrote:

From: leon Heller <leon355@...>
Subject: Re: [Homebrew_PCBs] Re: Muriatic Acid and Hydrogen Peroxide Fumes
To: Homebrew_PCBs@yahoogroups.com
Date: Sunday, June 28, 2009, 6:26 PM











    
            
            


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

From: "Charles" <lancedulak@yahoo. com>

To: <Homebrew_PCBs@ yahoogroups. com>

Sent: Sunday, June 28, 2009 6:00 PM

Subject: [Homebrew_PCBs] Re: Muriatic Acid and Hydrogen Peroxide Fumes



> Ive been EXTREMELY careful of fumes using this method and am going to CuCL 

> exclusively. FCL is just too poisonous to the environment (imho it should 

> be outlawed). The reason im so cautious with this is ive played with 90% 

> nitric and copper and breathed in the fumes and it was bad. Sickness, 

> nausea and i could tell acidic fumes had done damage to my lungs and 

> airway. That is from a good breath or two of the stuff, no more. I dont 

> know the specifics but i bet the gaseous byproducts are similar or 

> identical. I wouldnt etch indoors using this process period without some 

> kind of fume control (your kitchen stove hood might work but i dont want 

> to think about the effect).

>

> Btw you think watching a fast etch is cool you should see what high grade 

> nitric does to copper (and that is without an oxygen source).



FeCl3 isn't hazardous to the environment, it's actually used by water 

companies in their treatment plants! Copper can cause problems in effluent 

as it kills the bacteria that break down sewage, but the amount that gets 

flushed away when etching PCBs is negligible compared to the copper that is 

leached from copper pipework in the home.



Leon

--

Leon Heller

Amateur radio call-sign  G1HSM

Yaesu FT-817ND transceiver

Suzuki SV1000S motorcycle

leon355@btinternet. com

http://www.geocitie s.com/leon_ heller 




 

      

    
    
	
	 
	
	








	


	
	


      

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

Reasonable care must be taken fore sure.
The main things are to keep the concentrated HCl in a sealed bottle,
and you should run your CuCl tank with a relatively low HCl
concentration. Then you will not have any problems with fumes or
rusting.

ST

On Mon, Jun 29, 2009 at 12:47 AM, Simao Cardoso<simaocardoso@...> wrote:

> I also have bad stories with having CuCl etchant and HCl on the self on
> the same room as hundred of tools and an CNC router 'in construction'.
> Lets say you need to have very careful with your containers and
> phosphoric acid can give a nice look again to your tools but can't give
> back the polish of expensive  CNC parts. Ventilation and sealed
> containers are mandatory.
>
>

Simao Cardoso wrote:
> 

> Nitric acid is an Oxidizing. The gas produced in the copper reaction is
> nitric oxide which is toxic. People shouldn't use it as copper etch has
> already discussed here long time ago by Adam Seychell, its hazard toxic
> and air pollutant.
> But in my quest for metallic resist compatible etchants i found one
> using nitric acid which i experimented. It's basically the same stuff as
> peroxide-sulfuric etchant, but using nitric acid as the oxidizer. Since
> i can't find here hydrogen peroxide in more than 9% solution, but i get
> nitric acid in 60% at less 1.70eur/liter, it seem a cheap etch with easy
> copper electrowinnig has i wanted. In peroxide-sulfuric the solution
> amount is always increasing, so you always need some disposal. But with
> nitric acid it consumes water, and the mixture of nitric sulfuric can
> regenerate one HNO3 molecule in each 3 spent while makes CuSO4, besides
> the air pollutant nitric oxide seems a nice etchant. I made various
> tests but, the nitric acid attacks the toner almost completely... I also
> etch a copper piece an got an enormous amount of CuS04 freezing it. The
> solution turn almost clear, so almost all copper is easily deposited.
> Only now i found a source of pure tin (in Australia) and i still have to
> try the phosphorous mixture with plated tin as resist.
> 

A nice effort on finding a suitable etchant for metallic etch resist. I 
tried persulfate but that attacked tin enough to make it unreliable. 
 From your description the nitric-sulfuric mix sounds like the best 
hobby etchant compatible with pure tin metallic resist. The alkaline 
ammonia chloride type works great on tin resists, not even affecting the 
mirror shine tin surface. The downside is the need for regular ammonia 
replenished due to NH3 loss. This etchant is regenerated with ammonium 
chloride salt, concentrated aqua ammonia, water, and air. Alkaline 
ammonia chloride etches relatively fast, up there with fresh FeCl3.


Have you tried etching a mix of concentrated HCl and HNO3, also known as 
Aqua Regia ?  That should give you a run for your money.

On Fri, 2009-07-03 at 09:46 +1000, Adam Seychell wrote:

> A nice effort on finding a suitable etchant for metallic etch resist.
> I 
> tried persulfate but that attacked tin enough to make it unreliable. 
> From your description the nitric-sulfuric mix sounds like the best 
> hobby etchant compatible with pure tin metallic resist. The alkaline 
> ammonia chloride type works great on tin resists, not even affecting
> the 
> mirror shine tin surface. The downside is the need for regular
> ammonia 
> replenished due to NH3 loss. This etchant is regenerated with
> ammonium 
> chloride salt, concentrated aqua ammonia, water, and air. Alkaline 
> ammonia chloride etches relatively fast, up there with fresh FeCl3.
> 
> Have you tried etching a mix of concentrated HCl and HNO3, also known
> as 
> Aqua Regia ? That should give you a run for your money.
> 

Funny! Yes is a crazy thing. But is PATENTED for pure tin metallic
resists! 

Like i said is like the peroxide-sulfuric etchant, and from a searchable
post from you, you know about peroxide-sulfuric with phosphoric acid and
additives to work as metallic resist etchant (And from you i know that
the tin don't end looking so good). I didn't said it explicitly but it
also uses phosphoric acid for tin resits (along with additives).

The thing etches copper, and i get a big amount of copper sulfate
easily. But is almost like Aqua regia that even etches gold. The toner
is there just to give the bath a black color :>

I found the sulfuric-nitric etchant searching for oxidants for a
sulfuric based etchant. You use a very good etchant and only at the 2rd
time i read it, i noted you use it outside. You are also the only author
I found with anything from ammonia sulfate etch. Your Ammonia MEA report
is a very clever way to get ride ammonia smell.

You know patents better than me, the ones i talk about are uspo 4632727
and 4497687.

But yes, is obvious what i will end using... Very Thanks!

>

uspo 4545850 and 4632727 instead. My mistake.