The hcl/peroxide mix has to be occaisionally "regenerated" by having air put through it, like an aquarium bubbler/stone. If it's completely activated with copper and fresh or regenerated, you can actually etch with just a sponge it's that fast.
My bottle of muriactic acid is at least 10 years old.
I only use about a shot glass of the stuff each time I etch boards.
I think thats about 50 ml.... so a 950ml bottle will etch 19 batches......
and a bottle costs $5 at the local hardware store......
so I don't think I will be using ferric chloride ever again.
On 10/08/2016 09:18 PM, soffee83@... [Homebrew_PCBs] wrote:
Rob,
My guess is it's mainly for ferric chloride and stuff. That mix you and I are using seems to generate its own heat somehow, though I have heated it when it was acting weak. I still haven't figured out why mine got weak, but I'm guessing it's shelf life.
Take Care