Homebrew PCBs

Hello

I have been etching PCBs for years using ferrous chloride, but wanted to try cupric chloride.  I mixed hydrochloric acid and hydrogen peroxide, put some oxidized copper in it to get it started, but never really tried it.  I had some frustrating experiences because I had no idea that nylon should not be put into the solution.  I made a bubble tank which used zip ties, and they dissolved and poisoned the solution.  I made it again, but used a nylon string to lower the test board into the solution.  The string dissolved.  After some Internet research, I realized what was happening, but apparently this isn't a common problem.  I had a lot of trouble tracking the issue down.

I put the solution and tank away for a few years and just used FeCl3 for the few boards I made at home.  Today, I decided to get the solution out and try it.  The air hose going into the tank was oily feeling, but I suspect it's silicone leeching from the hose (some of the solution was in the hose).  The hose inside the tank was even worse.  Also, a seal around the lid of the tank (essentially a water pitcher from Target) was degraded and crumbled away when I took the lid off.  The hose was a plain fish tank type hose I got from Lowe's.  

I'd like to hear some other experiences regarding this.  I'm about to give up on cupric chloride and go back to ferrous or try sodium persulfate.  It seems that the cupric attacks nearly everything, well almost everything except the tank itself.

It sounds like HCL is reacting with your equipment. Try using HCL
resistant materials. Google search found this useful website.
http://www.coleparmer.com/techinfo/chemcomp.asp



On Sat, Sep 24, 2011 at 3:44 PM, hondgm <hondgm@...> wrote:

> **
>
>
> Hello
>
> I have been etching PCBs for years using ferrous chloride, but wanted to
> try cupric chloride. I mixed hydrochloric acid and hydrogen peroxide, put
> some oxidized copper in it to get it started, but never really tried it. I
> had some frustrating experiences because I had no idea that nylon should not
> be put into the solution. I made a bubble tank which used zip ties, and they
> dissolved and poisoned the solution. I made it again, but used a nylon
> string to lower the test board into the solution. The string dissolved.
> After some Internet research, I realized what was happening, but apparently
> this isn't a common problem. I had a lot of trouble tracking the issue down.
>
> I put the solution and tank away for a few years and just used FeCl3 for
> the few boards I made at home. Today, I decided to get the solution out and
> try it. The air hose going into the tank was oily feeling, but I suspect
> it's silicone leeching from the hose (some of the solution was in the hose).
> The hose inside the tank was even worse. Also, a seal around the lid of the
> tank (essentially a water pitcher from Target) was degraded and crumbled
> away when I took the lid off. The hose was a plain fish tank type hose I got
> from Lowe's.
>
> I'd like to hear some other experiences regarding this. I'm about to give
> up on cupric chloride and go back to ferrous or try sodium persulfate. It
> seems that the cupric attacks nearly everything, well almost everything
> except the tank itself.
>
>  
>


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

Thank you for your reply.  I assumed it was the cupric chloride, not HCl since this was supposedly no longer plain HCl.  However I'm no chemistry expert.  I'm just looking for the best etchant, which in my case means fast, environmentally friendly and stable.  Being translucent is nice too so the progress can be viewed.  

The website looks interesting.  I didn't even think of looking for something like this since I'm sort of lost on the chemical stuff.

--- In Homebrew_PCBs@yahoogroups.com, Lawrence Kincheloe <lokimail@...> wrote:

>
> It sounds like HCL is reacting with your equipment. Try using HCL
> resistant materials. Google search found this useful website.
> http://www.coleparmer.com/techinfo/chemcomp.asp
> 
> 
> 
> On Sat, Sep 24, 2011 at 3:44 PM, hondgm <hondgm@...> wrote:
> 
> > **
> >
> >
> > Hello
> >
> > I have been etching PCBs for years using ferrous chloride, but wanted to
> > try cupric chloride. I mixed hydrochloric acid and hydrogen peroxide, put
> > some oxidized copper in it to get it started, but never really tried it. I
> > had some frustrating experiences because I had no idea that nylon should not
> > be put into the solution. I made a bubble tank which used zip ties, and they
> > dissolved and poisoned the solution. I made it again, but used a nylon
> > string to lower the test board into the solution. The string dissolved.
> > After some Internet research, I realized what was happening, but apparently
> > this isn't a common problem. I had a lot of trouble tracking the issue down.
> >
> > I put the solution and tank away for a few years and just used FeCl3 for
> > the few boards I made at home. Today, I decided to get the solution out and
> > try it. The air hose going into the tank was oily feeling, but I suspect
> > it's silicone leeching from the hose (some of the solution was in the hose).
> > The hose inside the tank was even worse. Also, a seal around the lid of the
> > tank (essentially a water pitcher from Target) was degraded and crumbled
> > away when I took the lid off. The hose was a plain fish tank type hose I got
> > from Lowe's.
> >
> > I'd like to hear some other experiences regarding this. I'm about to give
> > up on cupric chloride and go back to ferrous or try sodium persulfate. It
> > seems that the cupric attacks nearly everything, well almost everything
> > except the tank itself.
> >
> >  
> >
> 
> 
> [Non-text portions of this message have been removed]
>

To expand on this, I'm a bit lost as to where to find materials that the solution doesn't attack.  All the tutorials I've seen on cupric chloride make no mention of incompatible plastics; they only talk about metals.  It makes me think I'm the only one having this problem.

I've taken a look at the Cole-Palmer website and can find what materials are acid-resistant, specifically air hose, however finding the associated product to buy is confusing and often very expensive.

I'm not looking for someone to do that work for me of course.  I simply don't want to re-invent the wheel.  Has anyone had trouble with cupric chloride solutions eating away at the plastics in the tank?  What do you use for the container and air hose?


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

>
> Hello
> 
> I have been etching PCBs for years using ferrous chloride, but wanted to try cupric chloride.  I mixed hydrochloric acid and hydrogen peroxide, put some oxidized copper in it to get it started, but never really tried it.  I had some frustrating experiences because I had no idea that nylon should not be put into the solution.  I made a bubble tank which used zip ties, and they dissolved and poisoned the solution.  I made it again, but used a nylon string to lower the test board into the solution.  The string dissolved.  After some Internet research, I realized what was happening, but apparently this isn't a common problem.  I had a lot of trouble tracking the issue down.
> 
> I put the solution and tank away for a few years and just used FeCl3 for the few boards I made at home.  Today, I decided to get the solution out and try it.  The air hose going into the tank was oily feeling, but I suspect it's silicone leeching from the hose (some of the solution was in the hose).  The hose inside the tank was even worse.  Also, a seal around the lid of the tank (essentially a water pitcher from Target) was degraded and crumbled away when I took the lid off.  The hose was a plain fish tank type hose I got from Lowe's.  
> 
> I'd like to hear some other experiences regarding this.  I'm about to give up on cupric chloride and go back to ferrous or try sodium persulfate.  It seems that the cupric attacks nearly everything, well almost everything except the tank itself.
>

hondgm wrote:
>   
> 
> To expand on this, I'm a bit lost as to where to find materials that
> the solution doesn't attack. All the tutorials I've seen on cupric
> chloride make no mention of incompatible plastics; they only talk
> about metals. It makes me think I'm the only one having this problem.


Using 'HCl nylon' on the search box of this group gives very explanatory
messages like this (among others):
http://tech.groups.yahoo.com/group/Homebrew_PCBs/message/7161
http://tech.groups.yahoo.com/group/Homebrew_PCBs/message/1412

Most people use cheap tall food containers for this, they came with the
plastic type marked with its recycling symbol.  Choose PP, HDPE/LDPE. My
tank is myself made off PMMA, the drilled air bubbling tube is PVC and
the holder is titanium. Nylon is a trademark for Polyamide which i think
wont resist in any acid.

--- In Homebrew_PCBs@yahoogroups.com, Simao Cardoso <simaocardoso@...> wrote:
>
> hondgm wrote:
> >   
> > 
> > To expand on this, I'm a bit lost as to where to find materials that
> > the solution doesn't attack. All the tutorials I've seen on cupric
> > chloride make no mention of incompatible plastics; they only talk
> > about metals. It makes me think I'm the only one having this problem.
> 
> 
> Using 'HCl nylon' on the search box of this group gives very explanatory
> messages like this (among others):
> http://tech.groups.yahoo.com/group/Homebrew_PCBs/message/7161
> http://tech.groups.yahoo.com/group/Homebrew_PCBs/message/1412
> 
> Most people use cheap tall food containers for this, they came with the
> plastic type marked with its recycling symbol.  Choose PP, HDPE/LDPE. My
> tank is myself made off PMMA, the drilled air bubbling tube is PVC and
> the holder is titanium. Nylon is a trademark for Polyamide which i think
> wont resist in any acid.
>
Ahh, there is some.  I must have been overthinking the search terms, as I was trying "cupric plastic compatibility" and similar.

When I tried it I kept the solution in an plastic milk bottle. The 
plastic seemed OK.

Leon
-- 
Leon Heller
G1HSM

Can someone please tell me why not just use Amonium Persulfate.  It seems freely available, that is what I am using and it works fine, I find that if maintained at a temperature of 120 degF the etching is complete in 20 minutes.  What am I missing?

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

CuCl can be regenerated indefinitely and is therefore cheaper.
Also it can be made from chemicals that are even more readily
available than Amonium Persulphate.

There is no reason not to use your Persulphate if you can get it
easily and it works for you.

ST

On Tue, Sep 27, 2011 at 3:49 PM, Tom Biery <judsquare@...> wrote:
>
> Can someone please tell me why not just use Amonium Persulfate.  It seems freely available, that is what I am using and it works fine, I find that if maintained at a temperature of 120 degF the etching is complete in 20 minutes.  What am I missing?
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>
>

I used AP for years it worked out great for me.  The solution doesn't keep too long so I would just make up what I needed for that job. Heating is the key, it doesn't work unless it's hot.  Also, a few ppm of HgCl2 really increases the etching speed but that adds a toxic element to the mix, but doesn't take much at all.  These days, Hg is one of those bad actor metals, though I must admit to haveing quite a few milligrams in my teeth and played with a few Hg covered pennies.  Unless you have a proper and legal spent etchant disposal process it's use is not advised.

Craig 

--- In Homebrew_PCBs@yahoogroups.com, Tom Biery <judsquare@...> wrote:

>
> 
> Can someone please tell me why not just use Amonium Persulfate.  It seems freely available, that is what I am using and it works fine, I find that if maintained at a temperature of 120 degF the etching is complete in 20 minutes.  What am I missing?
> 
> [Non-text portions of this message have been removed]
>

On 28/09/2011 16:31, designer_craig wrote:
> I used AP for years it worked out great for me. The solution doesn't
> keep too long so I would just make up what I needed for that job.
> Heating is the key, it doesn't work unless it's hot. Also, a few ppm of
> HgCl2 really increases the etching speed but that adds a toxic element
> to the mix, but doesn't take much at all. These days, Hg is one of those
> bad actor metals, though I must admit to haveing quite a few milligrams
> in my teeth and played with a few Hg covered pennies. Unless you have a
> proper and legal spent etchant disposal process it's use is not advised.

When I used AP many years ago, I used to add a small amount of common 
salt instead of HgCl2. It made it a lot faster.

Leon
-- 
Leon Heller
G1HSM

From what I understand is that the plastic of most Mild Bottles are designed to break down.  I know that sunlight causes them to break down.

Also know don't use a fish tank that is put together with sealant as the sealant will break down over time and leak.

Plastic of most food containers and storage containers seems to work OK.  Glass may be the best choice.

Ben


--- In Homebrew_PCBs@yahoogroups.com, Leon Heller <leon355@...> wrote:

>
> When I tried it I kept the solution in an plastic milk bottle. The 
> plastic seemed OK.
> 
> Leon
> -- 
> Leon Heller
> G1HSM
>

On 01/10/2011 02:31, Ben L wrote:
>  From what I understand is that the plastic of most Mild Bottles are
> designed to break down. I know that sunlight causes them to break down.
>

My milk bottle with cupric chloride was still OK after a couple of 
years. I use them for FeCl3 and developer, as well. I keep them in an 
old washing up bowl, in case they do start to leak.

Leon
-- 
Leon Heller
G1HSM