copper plating - Electrode Tips

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Mike,

For copper plating tungsten, for easy soldering....

I found "ZEP Commercial Root Kill" at Home Depot.  It is used to keep roots
out of sewer lines.  99.0% Copper Sulfate Pentahydrate and 1% "other".  I
assume that is "the right stuff"...  I could not find anything specific
that was sulfuric acid...  Mostly caustic lye type compounds...

I dissolved "some" in water and added a section of 1/4 inch copper tube
(anode (+)) and a tungsten rod (cathode (-)).  Didn't work well at all.
Just formed soft black spongy stuff (really cool though).  More current
more mess...

I then found some Phosphoric Acid used as the common "PH Down" for
adjusting the PH of aquarium water.  With a very liberal squirt of the
acid, the reaction changed completely to an obviously much better state.
So the acid part seems very important.  I tried a lot of current with a
little bubbling and the soft layer of copper wipes off.  I am trying a much
lower current now...  I can probably get sulfuric acid from the pharmacy.
One of the local pharmacists looks like he personally tests everything
before he sells it... he probably has the right attitude about ordering
"anything" I need :-))

A guy at work did a beautiful perfect shiny copper plating job a few months
back on his desk.  He was explaining it all to me but one of the main
ingredients of the plating bath was human urine...  and then I didn't want
to know anymore :-p  I'll go ask him more now that I know the true value of
such information...

I just checked the 1/2 inch long bit of 1/8 inch rod in the solution at
10mA.  A "little" better but still rubs off...  I think the solution
contents are probably a bit critical...  Needs more research on how one can
make the bath with readily available chemicals.  I do have a nice gram
scale...  Seems to need better chemicals....

Chemystery was never my strong subject, but doing me best :-))

I also got some stuff to try some silver brazing and all that.  Wow!, you
think I am bad at chemystery!!  I solder extremely well.  But welding...  I
can incinerate just about anything with a MIG welder and my fancy MAPP gas
torch has a "ludicrous" heat setting...  So I am all ready to go!!! :-D
The guys at the welding shop have now learned to try and keep the crazy
long haired guy in the suit on the premises while I am asking for a few
boxes of acetylene and a few bags of liquid oxygen cause "I want to heat
something up really bad"...  While the guy in back frantically calls the
BATF ;-)))  Fortunately the day job gets a ton of $$$$ stuff from there so
they are super nice no mater what...  They usually give me fun dewars of
LN2 nice and cheap just to get rid of me...  When needed, asking for an
MSDS sheet for leather welding gloves always works :-)))

I have some pals that can do this stuff for me, but having too much fun
myself :-)))

Cheers,

	Terry



>At 06:46 PM 8/12/2001 -0400, you wrote: 
>  Yes, copper sulfate is a commonly used algicide.   Although all the 
>plating baths I have ever used contained sulfuric acid, I don't know that it 
>is really necessary.  I think it merely adds to the conductivity of the 
>solution and increases the efficiency.  That probably doesn't really matter 
>if one is just plating a small piece or two.   
>  Actually,  if you want to take the time to do it, you can make a saturated 
>solution of copper sulfate and use a lead anode(+ electrode for anyone 
>unfamiliar with the term).  You will deposit copper metal on the cathode, 
>release oxygen bubbles from the lead anode and generate sulfuric acid.  The 
>hydrogen ions (from splitting water molecules) replace the copper ions in the 
>solution.  Once you have generated a bit of sulfuric acid, you can replace 
>the lead anode with a hunk of copper to continue plating forever with that 
>solution.  You might want to add a bit more copper sulfate crystals if the 
>concentration get very low from the acid generation. 
>Mike 
>
>