Homebrew PCBs

Muriatic Acid (28%) and Hydrogen Peroxid (3%)?  Homemade stuff.
Ammonium Persulphate.  Powder?  Liquid?
Ferric Chloride?
I hear that ferric chloride is the quickest but that Ammonium Persulphate is a clear solution that allows you to watch the etching process..

"rickwendel763242" <rickwendel763242@...> writes:
> Muriatic Acid (28%) and Hydrogen Peroxid (3%)?  Homemade stuff.
> Ferric Chloride?

I've used both of these.  Started with FeCl, switched to CuCl (made
from HCl+H2O2).  Why?  First, FeCl is getting hard to find locally.
Second, FeCl stains.  Third, CuCl can be air regenerated, so there's
less to throw away over time.

Neither of those are see-through, but I do put a strong light behind
the tank and can see enough.  I usually remove the board, rinse, and
inspect with a mag visor anyway.

Ammonium persulphate is clear, but can not be regenerated, and can be a
little finicky to work with if the ph and specific gravity aren't within
certain parameters. It's also the slowest etching method. This is really
good for teachers, otherwise, just pull it, rinse it, and inspect it. You
can't really see the traces that well when it's in the tank anyways, so
you'll still have to pull it out and rinse it to check the traces with a
loupe. It's really only good for the ooohs and ahhhs of first timers who
have never seen metal dissolve.

 Acid Cupric Chloride is my favorite method, since you can continue to
regenerate it with O2, and you never have to dispose of any of it.

Here's a really good article on how to etch with Acid Cupric Chloride.
http://members.optusnet.com.au/~eseychell/PCB/etching_CuCl/index.html<http://members.optusnet.com.au/%7Eeseychell/PCB/etching_CuCl/index.html>

Check it out. Easy to do, cheaper than the rest, and just as effective at
cutting nice sharp traces.

Peace!
-Mike

On Thu, Apr 23, 2009 at 8:05 PM, rickwendel763242 <
rickwendel763242@...> wrote:

>
>
> Muriatic Acid (28%) and Hydrogen Peroxid (3%)? Homemade stuff.
> Ammonium Persulphate. Powder? Liquid?
> Ferric Chloride?
> I hear that ferric chloride is the quickest but that Ammonium Persulphate
> is a clear solution that allows you to watch the etching process..
>
>  
>


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

rickwendel763242 wrote:
> Muriatic Acid (28%) and Hydrogen Peroxid (3%)?  Homemade stuff.


This wins HANDS DOWN

It takes 4 minutes in my setup (without any kind of heating)

It is transparent enough in my opinion to see what is happening.

bye
Alessio

Alessio,  I agree with you on this.  I do not understand
the people that say the other methods are better.


Derward

  ----- Original Message ----- 
  From: Alessio Sangalli 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Friday, April 24, 2009 3:45 PM
  Subject: Re: [Homebrew_PCBs] What is the best etching solution;





  rickwendel763242 wrote:
  > Muriatic Acid (28%) and Hydrogen Peroxid (3%)? Homemade stuff.

  This wins HANDS DOWN

  It takes 4 minutes in my setup (without any kind of heating)

  It is transparent enough in my opinion to see what is happening.

  bye
  Alessio



  

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

"Derward Myrick" <wdmyrick@...> writes:
> Alessio,  I agree with you on this.  I do not understand
> the people that say the other methods are better.

Keep in mind that one benefit of the HCl/H2O2 etchant is it's reusable
- but it gets converted to CuCl etchant, which is not see-through any
more, and requires some fiddling to keep it etch-worthy.  Still simple
to me, but not nearly as simple as "mix and etch".

I'm not sure about that.
The CuCl is just sitting there, waiting for me to drop in a board all
year round. It doesn't go bad or require me to mix up a new batch.
Maintainance is minimal, and can be done while the board is etching
which is efficient use of time.

I can still see through my CuCl with a bright light from the other
side, but now the tank is positioned inconveniently for that and I
lift the board out for final inspection.

ST

On Sat, Apr 25, 2009 at 5:53 PM, DJ Delorie <dj@...> wrote:
>  Still simple
> to me, but not nearly as simple as "mix and etch".
>

Stefan Trethan <stefan_trethan@...> writes:
> I'm not sure about that.
> The CuCl is just sitting there, waiting for me to drop in a board all
> year round. It doesn't go bad or require me to mix up a new batch.
> Maintainance is minimal, and can be done while the board is etching
> which is efficient use of time.
> 
> I can still see through my CuCl with a bright light from the other
> side, but now the tank is positioned inconveniently for that and I
> lift the board out for final inspection.

Mine is in the same state, but I still check the pH and specific
gravity once in a while, and occasionally add more HCl.

I am used to the H2O2 + HCL mix that's so cheap I use fresh mix everytime, but not to the CuCl one.
What advantage is there using Cucl for casual needs, as it seems to need more involvment than just mix two ( + water ! ) liquids ?

What is the mix for the Hydrogen Peroxide, Muratic acid for a 'proper
mixture'? (Yea, I'm a newbie, so
excruciating details are welcome.)

IHS ... Jack

On Sat, Apr 25, 2009 at 3:07 PM, jj_winkel <jj.winkel@...> wrote:
> I am used to the H2O2 + HCL mix that's so cheap I use fresh mix everytime, but not to the CuCl one.
> What advantage is there using Cucl for casual needs, as it seems to need more involvment than just mix two ( + water ! ) liquids ?
>
>
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>
>

Jack Coats wrote:
> What is the mix for the Hydrogen Peroxide, Muratic acid for a 'proper
> mixture'? (Yea, I'm a newbie, so
> excruciating details are welcome.)

I use a liter of H2O2 and half a liter of HCl.

Put the H2O2 first and the muriatic acid on it, not the opposite they say.

bye
as

jj_winkel wrote:
> I am used to the H2O2 + HCL mix that's so cheap I use fresh mix everytime,

Wel you throw it away all the times? I do not know how many boards you
do everytime but it sounds like a waste to me...

jj_winkel wrote:
> I am used to the H2O2 + HCL mix that's so cheap I use fresh mix everytime, but not to the CuCl one.
> What advantage is there using Cucl for casual needs, as it seems to need more involvment than just mix two ( + water ! ) liquids ?
> 
> 
Air regenerated CuCl2 has its benefits with permanent bubble etch tank
installations, because it requires minimal handling of chemicals during
its operating life. Depending the tank volume and rate of copper etched,
the normal maintenance involves additions of concentrated HCl about
every 10 to 20 PCBs etched. Unlike persulfates and H2O2, the CuCl2
solutions have an indefinite shelf life.

The etch rate of air regenerated cupric chloride is about %50 speed of
fresh ferric chloride under equal conditions.

I would agree, that for people making only the occasional *small* PCB,
then preparing heated etchant into a plastic lunch box and then manually
rocking the PCB is probably the ideal method.

>
> What is the mix for the Hydrogen Peroxide, Muratic acid for a 'proper
> mixture'? (Yea, I'm a newbie, so excruciating details are welcome.)
> 
> IHS ... Jack

Here in France it is easy and cheap enough to get "masonry" grade H202 (35% in weight or 130 in volume)used for wood bleaching and stains removal, and HCl (33%), 
so my recipe for 1 liter is : 750mL water + 50mL H2O2 + 200mL HCl in that order, etching time is about 8 to 10 minutes,
this gives time to control the etching and stop it when OK.
I have tried with less dilution, but as the solution is exothermic, it produces such a volcano and heat that fine traces can be etched thru or resist lifted before you have a chance to remove the board.  
But usually I only prepare 1/4 L (250 mL) enough for small boards everytime, as the solution cannot be kept and as it deteriorates rapidly it is best to throw it away. 
I have made a very small vertical tank by glueing two CD box covers, it contains about 200mL and I dip in boards up to 5x4" (I normally leave as much copper as possible, only etching around the traces)
JJ.

--- In Homebrew_PCBs@yahoogroups.com, "jj_winkel" <jj.winkel@...> wrote:
>
> >
> > What is the mix for the Hydrogen Peroxide, Muratic acid for a 'proper
> > mixture'? (Yea, I'm a newbie, so excruciating details are welcome.)
> > 
> >>
I just had my first experience yesterday.  I used the HP laser printer at work to make the photocopy art work.  I used a cheap $19 iron from a local hardware to transfer.  I used 1 part Muriatic acid to 2 parts Peroxide to etch.

I put the boards in a smaller portion (one cup to two cups)of this concoction and agitated them lightly with 2 of those disposable metal handled glue brushes.  It worked PERFECT!  Every so often I switched from board to board and rubbed lightly with the brushes (kind of held the board down with one and spun the other brush lightly).  Maybe 5 minutes later, I was down to clear boards.  I rinsed them, dried them and wiped them clean with acetone.  BINGO ..... 5 perfect boards.  I was so happy.

I basically used the info at http://www.fullnet.com/~tomg/gooteepc.htm and had great results.  Ken has lots of experience and there is alot of info there for the newbie. (like me)

jj_winkel wrote:

> Here in France it is easy and cheap enough to get "masonry" grade
> H202 (35% in weight or 130 in volume)used for wood bleaching and
> stains removal, and HCl (33%), so my recipe for 1 liter is : 750mL
> water + 50mL H2O2 + 200mL HCl in that order, etching time is about 8
> to 10 minutes,

In the US I haven't found 35% H2O2 so I use the 3% one. Result is that I
do not have to add water to the mix.


>  But usually I only prepare 1/4 L (250 mL) enough for small boards
> everytime, as the solution cannot be kept and as it deteriorates
> rapidly it is best to throw it away.

Why do you say this. We discussed long that this solution is virtually
eternal...

bye
as

The etchant will only keep as long as it is regenerated (usually with
oxygen from H2O2 or air).

Especially with 3% H2O2 it is said to be hard/impossible to regenerate
this etchant as it adds too much water in the long run.

ST

On Sun, Apr 26, 2009 at 8:01 PM, Alessio Sangalli <alesan@...> wrote:

>>  But usually I only prepare 1/4 L (250 mL) enough for small boards
>> everytime, as the solution cannot be kept and as it deteriorates
>> rapidly it is best to throw it away.
>
> Why do you say this. We discussed long that this solution is virtually
> eternal...
>
> bye
> as

Stefan Trethan wrote:
> The etchant will only keep as long as it is regenerated (usually with
> oxygen from H2O2 or air).
> 
> Especially with 3% H2O2 it is said to be hard/impossible to regenerate
> this etchant as it adds too much water in the long run.

I thought we also said the bubbler found in many etching tanks does this
function to regenerate the etchant - and anyway in France it seems it's
easy to find 35% H2O2...

Anyway - I like this etchant. I would never use FeCl anymore :)

bye
as

As an aside, I was looking on the 'net trying to find out how to MAKE
at home Hydrogen Peroxide.

Any one have a reference for me or a suggestion as to where I might find out?

TIA, Jack

I think you are better off sourcing the oxygen elsewhere.
If you want to avoid evaporation / vapor escape issues with air
bubbling you could feed pure oxygen from a bottle into a downstream
reactor and dissolve it completely.
How to build a downstream reactor can be found on various fishtank
sites (basic idea tube with water pumped downwards, gas bubbles rising
inside against the current making little to no headway).

Probably you could even create the oxygen with electrolysis and let
the hydrogen dissipate (slightly dangerous don't smoke ;-) ).

I was also thinking that it should be possible to add chlorine in some
other way (other than liberating it with oxygen from HCl that is).
References state that industrial processes sometimes used (very highly
dangerous) chlorine gas. Maybe it is possible to get the chlorine from
pool supply or bleach products, perhaps even safely. Don't come
complaining to me if you kill yourself attempting that one though....


Probably by far the simplest solution is air bubbling. With a solution
mixing a downstream reactor with a partially enclosed system
efficiency can probably pushed up and evaporation / corrosive vapor
escape reduced to acceptable levels.

ST

On Sun, Apr 26, 2009 at 10:06 PM, Jack Coats <jack@...> wrote:
> As an aside, I was looking on the 'net trying to find out how to MAKE
> at home Hydrogen Peroxide.
>
> Any one have a reference for me or a suggestion as to where I might find out?
>
> TIA, Jack
>

> Why do you say this. We discussed long that this solution is virtually
> eternal...
> 
It is the CuCl2 (Cupric Acid) solution that is "eternal" not the H2O2+Hcl one.
The CuCl2 bath must be prepared beforehand and looked after periodically, you can diy as follows :
770 ml ordinary warm tap water (40°C) (or 500ml if 3% H2O2)
200 ml Hcl (33%)
30 ml H2O2 (35%) (or 300 ml if 3% H2O2)
40 g pure metal copper (chips or electrical grade wire)
Up to complete dissolution, this can take several hours or days ....
I am not a chemist and have never done it myself, but I understand that if you have to use a several liters etching tank, this is probably the best economical and "green" solution.

I believe it has been said that 30 to 35% Hydrogen peroxide can be found at Beauty Parlor supply stores!
3% is too weak to bleach Hair!
73
Mike



________________________________

From: Alessio Sangalli <alesan@...>
To: Homebrew_PCBs@yahoogroups.com
Sent: Sunday, April 26, 2009 2:01:05 PM
Subject: Re: [Homebrew_PCBs] Re: What is the best etching solution;





jj_winkel wrote:

> Here in France it is easy and cheap enough to get "masonry" grade
> H202 (35% in weight or 130 in volume)used for wood bleaching and
> stains removal, and HCl (33%), so my recipe for 1 liter is : 750mL
> water + 50mL H2O2 + 200mL HCl in that order, etching time is about 8
> to 10 minutes,

In the US I haven't found 35% H2O2 so I use the 3% one. Result is that I
do not have to add water to the mix.

> But usually I only prepare 1/4 L (250 mL) enough for small boards
> everytime, as the solution cannot be kept and as it deteriorates
> rapidly it is best to throw it away.

Why do you say this. We discussed long that this solution is virtually
eternal...

bye
as




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

Duh

Hydrogen peroxide costs about 50 to 75 cents per quart in any drugstore.

A gallon of muriatic acid (hydrochloric acid) costs about 1 dollar in 
supermarket
or garden/pool supply store. A bit more costly (a buck fifty) at Ace 
Hardware.

Why reinvent the wheel?

Roland F. Harriston, PD




On 4/26/2009 1:06 PM, Jack Coats wrote:
>
>
> As an aside, I was looking on the 'net trying to find out how to MAKE
> at home Hydrogen Peroxide.
>
> Any one have a reference for me or a suggestion as to where I might 
> find out?
>
> TIA, Jack
>
> 
> ------------------------------------------------------------------------
>
>
> No virus found in this incoming message.
> Checked by AVG - www.avg.com
> Version: 8.5.287 / Virus Database: 270.12.4/2081 - Release Date: 04/26/09 09:44:00
>
>    



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

--- In Homebrew_PCBs@yahoogroups.com, michael tenore <wb2lcw@...> wrote:
>
> I believe it has been said that 30 to 35% Hydrogen peroxide can be
>found at Beauty Parlor supply stores!
> 3% is too weak to bleach Hair!

Beauty store hydrogen peroxide doesn't come in percentages that high.
IIRC, 20 volume hair bleach is 6% H2O2, 30 volume is 9% and 40 
volume is 12%. (The 30-35% variety of hydrogen peroxide is only
available from industrial suppliers.)


Regards, Bob

Sounds like a country to country difference here.  IMHO, each country gets
overly paranoid about different things.  Typically due to something that has
happened in their history that may cause 'regulations' to be put into place
to protect the public (often from themselves, at least in the USA).

This from a native Texan who is still trying to get used to the differences of
living in Tennessee.  I have been in TN for only 4, almost 5, years now.
Nation to nation differences are bigger yet!

IHS ... Jack

On Mon, Apr 27, 2009 at 11:21 AM, Bob_xyz <bob_barr@...> wrote:
> --- In Homebrew_PCBs@yahoogroups.com, michael tenore <wb2lcw@...> wrote:
>>
>> I believe it has been said that 30 to 35% Hydrogen peroxide can be
>>found at Beauty Parlor supply stores!
>> 3% is too weak to bleach Hair!
>
> Beauty store hydrogen peroxide doesn't come in percentages that high.
> IIRC, 20 volume hair bleach is 6% H2O2, 30 volume is 9% and 40
> volume is 12%. (The 30-35% variety of hydrogen peroxide is only
> available from industrial suppliers.)
>
>
> Regards, Bob
>
>
>
>
> ------------------------------------
>
> 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, Jack Coats <jack@...> wrote:
>
> What is the mix for the Hydrogen Peroxide, Muratic acid for a 'proper
> mixture'? (Yea, I'm a newbie, so
> excruciating details are welcome.)

To make 1l I used 700ml water, 200ml HCl and 100ml H2O2. My chemicals is 30%, so if you use weaker/stronger stuff the mixture will change.

Above is the mix I was recommended by my board supplier. Strips a whole copperboard in minutes.