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beanbag
12-07-2010, 12:19 AM
I have a set of glasses that I've been using for a long time. The temples are some kind of metal that has been plated with a brassy color. In some areas, this plating has worn off, and the underlying metal somehow corrodes into this greenish patina-like color (copper?). Anyway, is there a good/cheap/easy way to either re-plate this metal, or just coat it with some kind of clear coat or lacquer or whatever? This part of the temples squeezes against my head, so whatever I use, it should be inert or non-toxic.

PeteM
12-07-2010, 01:16 AM
In order of increasing cost:

Fine sand the surface and paint it. Will last a while.

If it's at the back end of the temples (by the ear), you could slip a piece of heat shrink tubing over the end -- your choice of colors.

You could also buy a used frame with near-matching temple pieces and swap them out.

If you have your prescription buy a set of new glasses, frames, lenses, coatings and all for around $50 from Zinni Optical.

baldysm
12-07-2010, 01:27 AM
The green stuff is probably copper. Copper is very often used as a initial plating before something else is electroplated on top.

Heat shrink tubing is a good idea. Something a little thicker might be the plastic dip you put tool handles into.

whitis
12-07-2010, 01:51 AM
That green crud can be abrasive and irritating to the skin as well as looking bad.

Heat shrink tubing is typically 2:1 shrink ratio, though you can get as much as 10:1 (in quantity). 4:1 is available from digikey. So, it is an issue of how big the tubing needs to be to fit over the ends (hinge or earpieces) vs how small it needs to shrink. If it doesn't shrink snug everywhere, that isn't necessarily a big problem but it should shrink snug over a significant portion

Caswell plating makes brush wand plating kits. You might have trouble matching the original color though, so you might end up plating everything.
http://www.caswellplating.com/kits/plugnplate.htm

If you have scraped off the corrosion, you can put some nail polish over the metal for protection (don't get it on the lenses).

beanbag
12-08-2010, 12:27 AM
Right now, I have clear scotch tape over it, and it seems to be holding up, except that it is corroded beneath the tape. I think I will go with painting, but would like a suggestion for a clear and durable paint. Maybe clear epoxy even??

Rich Carlstedt
12-08-2010, 12:33 AM
Get some of your wife's clear nail polish
It's tough and strong and cheap
Rich

KIMFAB
12-08-2010, 01:01 AM
Rich beat me to it, a big second on the nail polish and it comes in colors.

Dr Stan
12-08-2010, 10:50 AM
The frame is probably made from monel, a nickel/copper alloy which will produce the green coating (copper oxide) when it reacts with your body chemistry. My solution is to purchase titanium frames for my glasses. They are much less expensive than when they first came out, do not turn green, and last a very long time.

beanbag
12-08-2010, 05:41 PM
I went down to my local Target to get some nail polish. Even in "clear", there were so many variants, even within the same brand. Stuff like regular, "extreme wear", "diamond strength", top and base coat, fast drying version, gel formulations, nourishing and strengthening version, acrylic versions, etc etc.

Being a guy, I went and got the cheapest one.