From: John De Armond
Subject: Re: Copper plating
Date: Thu, 07 Jan 93 09:10:10 GMT

cyberman@exucom.com (Stephen R. Phillips) writes:
 
 
>I was attempting to copper plate soft soldered material with copper
>using copper sulfate a copper anode and a the object as the cathode.
 
>The result was a black sooty substance instead of Cu!
 
>1:	I was using electronics solder 60/40 (or is it 40/60?)
>2:	I used tap water to mix the CuSo4 solution.
>3:	I am using a variable current at 30 volts.
>4:	I have no clue to EXACTLY what I'm doing.
 
Way too much voltage/current.
 
I have set up a copper plating facility for my wife to use to plate
the lead came on certain kinds of stained glass work.  Here's my
mix:
 
To a gallon of water, add one lb copper sulfate.  I use root killer
(chunk copper sulfate) from the plumbing store because it is so cheap.
After the CuSO4 is dissolved using heat if necessary, add 2 cups of
sulfuric acid battery acid.  I buy Quail brand battery acid from
the local auto parts store in cardboard cased plastic bags.
 
Anode should be copper and of about the same surface area as the
work (cathode).  Voltage should be around 3 volts.  Current is
normally set as amps per unit area but since surface area is hard
to compute/measure, I just experiment until the finish is bright and
non-porous.  I have read that some sugar in the solution will brighten
the copper but I've not tried it.  For typical objects that will fit
in the 10 gal aquarium we use as a plating tank, a pair of D-cells
in series will plate many objects.
 
Cleanliness is absolutely vital.  Even a fingerprint will leave the
surface blemished and dark.  For stained glass objects, I first wash
the object in saturated baking soda solution to neutralize any acid
flux remaining.  I then wash in Alconox, a very strong laboratory
glassware cleaning detergent.  After rinsing and drying, I wipe
all surfaces with a clean rag soaked in 1,1,1 trichloroethane in order
to remove any residual grease and/or flux.  Go immediately to the
plating bath to avoid oxidation.
 
John