Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

I have a drum of food grade 35% hydrogen peroxide at my shop if
anyone is interested. We could put it in gallon jugs for shipping but
I'm not sure about UPS regulations on this material... it's pretty
potent stuff. I'm open to ideas if anyone wants it.

There is also a small chemical supplier near me who sells the
peroxide in gallon jugs. I'll call him on Monday and see if he ships
through UPS and post the details.

Almost any grade of sulfuric can be used if the concentration is high
enough. We used technical grade sulfuric which is 92.8% acid and
about 1.8 specific gravity.

Battery acid should work fine. Just pick up the container and if it
feels about twice as heavy as the same amount of water then it will
work. I saw a gallon jug of "sewer cleaner" the other day at a
hardware store. When I picked it up to read the label I knew it had
to be sulfuric because of the weight. Perhaps this could also be used.

If anyone wants to test out this method just use the 3% drug store
peroxide and some of this sulfuric sewer cleaner. The larger water
content of the 3% peroxide can offset the 75% amount of water needed
to make up the etchant. Just take two or three small bottles of 3%
peroxide and add some sulfuric until it starts etching.

This experiment should show how it works. No heater will be needed
since the addition of acid will heat things up as it is exothermic.


ADD THE ACID TO THE WEAK PEROXIDE SOLUTION IN THAT ORDER.

WEAR SAFETY GLASSES !!!!!!

Tom