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Stripping silver conductive paint from inside a copper mold

we are a company new to electroforming and have been at it for months, using wax substrates painted with silver nitrate as a conductive base for the copper electroform. we are getting decent results but the problem is cleaning out the inside of our molds. the molds are very irregular and organic and don't lend themselves to being cleaned easily by sandblasting alone. the silver paint seems to be end culprit. any suggestions on perhaps a chemical to strip it out? thanks in advance for any help!

John Keen
metal shop - Chester, New York
2006

Silver is soluble in nitric acid and wax is resistant to it. Only problem, nitric is dangerous and its waste regulated, so there will be dissposal issues.

Guillermo Marrufo
Monterrey, NL, Mexico
2006

Thanks for the tip! now assuming we arrange proper disposal using a bio-eco pick up company of sorts for refuse, would we use straight nitric or a dilute solution? once again thanks in advance for any help!

John Keen
metal shop - Chester, New York
2006

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I like fast things, I'll try first with the concentrated beast (very careful with it, eyes, lungs, skin, clothes!). Then if not satisfied with conditions (excessive fumes, odors, problems to dispose, etc.) I would trade off a little bit with successive dilution steps and see which one fits better.

Guillermo Marrufo
Monterrey, NL, Mexico
2006

Hey thanks again! we will give this a shot. thanks a lot for the tips. if there are monitors on here, thanks to finishing.com and all the experts that lend their knowledge. This site has become invaluable to me and our company. As newcomers trying to do everything by the book, I have been able to use the archives on here to troubleshoot on numerous occasions. So thanks again, and keep up the good work!

John Keen
metal shop - Chester, New York
2006

Ed. note: Thanks for the kind words, John. Yes, this site is "monitored", which means that we try to limit commercial postings, and within our limits we watch for misinformation. But the volunteer experts like Guillermo are what makes the site what it is, and I deeply appreciate their efforts, which makes my dream job possible -- Ted Mooney.