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Ted Mooney, P.E. RET
Pine Beach, NJ

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Need procedure to plate antique pewter part

Hello people,

I'm in the custom chrome plating business and I've got an old antique art deco cocktail mixer that I need to replate. The bulk of the piece is just a straight forward chrome strip, buff, reactivate the nickel and copper strike, etc. Worked fine except for the handle. Copper peeled and blistered. Our polisher thinks the base metal is pewter. I reactivated in 50% HCl with reverse current. I suspect this is where I went wrong. I will strip back down, but if anyone has any advice on how to proceed, I would appreciate it. It is a family heirloom and I would feel terrible screwing it up.

Thank You in advance

Hello, Trent. I'd bet that the handle is leaded and requires HF to activate.

Thanks Ted,
Any idea what the hydrofluoric acid concentration should be, and I'm assuming that no current is required? I don't like to have any more HF around than I absolutely need. Nasty stuff.

Thanks,

Hydrofluoric acid burns

Never use HF anywhere unless trained!
If you do, you MUST have the antidote gel on hand for instant use!

Calcium Gluconate
for HF acid burns

on eBay or

Amazon

(affil links)

I don't have hands-on experience in that, but the Electroplating Engineering Handbook [on AbeBooks or eBay or Amazon affil links] suggests pumice ⇦ this on eBay or Amazon [affil links] cleaning, followed by cathodic cleaning, followed by dip in 20% HF. Make sure you have calcium gluconate chemical burn cream.

on hand first, just in case.

My experience with pewter is :
Strip to base metal, polish to desired finish (bright), cyanide copper about 10 min. acid copper for an hour. bright nickel plate for 30 min. chrome flash for 1 min.

This seems to work for me quite well. Good luck.

Nope, not HF. For activation of lead alloys, use fluoboric acid, 10-15%, room temp, 30 seconds. Works better and much safer than HF. HCl is exactly wrong as it will form an insoluble film of lead chloride, and peeling is guaranteed.