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

I also agree that a milk bottle is the worst thing to store anything
in. However, most milk bottles I've seen are #2 recycling, not #5. I
have used FeCl, HCl + H2O2 mixtures, and acetone, in #2 and #5
plastics (I find it interesting that when you buy pure acetone for
woodworking, etc, it's in heavy metal cans with lids that are
impossible to remove, but if you go to a beauty supply store, they
sell pure acetone in #2 bottles with easily unscrewed caps. I've
bought a few of these, and now refill them from a 1 gallon jug.). #2
is what 2.5/5 gallon paint buckets are made out of. I think windshield
wiper fluid is also sold in #2 bottles, which are heavier than the
milk type. I use '13 qt sweater box' tupperware to etch in, which are
#5. I recycle the FeCl3 with peroxide, which I've heard also creates
CuCl in the mixture.

I was lucky not to have any FeCl leak when I used milk bottles to
temporarily store it to take it to be disposed of. However, I put some
water based varnish in one when the can it was in got damaged, and
didn't swap it into a new can soon enough - the bottle got a dent,
then leaked everywhere. Luckily nothing was damaged. Don't use milk
bottles.