Pickups causing corrosion?

jwargowski · Post by **jwargowski** » Fri Sep 29, 2006 7:17 am

A friend of mine has a 50's Gretsch Country Club, which he only plays rarely. On a recent occasion when he took it out to play, he noticed corrosion forming around the pickups, bad enough that it had eaten through one of the strings, and began removing the paint from the back of the pick guard, which then in turn darkened the finish under the pick guard.

He did the standard electronic corrosion clean up with a baking soda solution (probably not a great idea), changed the strings and put it away. A month later he noticed the problem returning. Has anyone ever seen a pickup turn into a battery ... or at least have this effect?

jingle_jangle · Post by **jingle_jangle** » Fri Sep 29, 2006 8:59 am

I think what he's got is outgassing from either the pickguard or possibly the plastic pickup surrounds.

Gretsch changed the materials that these are made of, from highly-reactive celluloid acetate to more neutral methyl methacrylate (acrylic) many moons ago.

doctorwho · Post by **doctorwho** » Fri Sep 29, 2006 9:27 am

Paul said:

celluloid acetate

I think you mean just "celluloid", a component of which is cellulose nitrate, a substance that, when degraded, would release the very corrosive nitric acid.

jingle_jangle · Post by **jingle_jangle** » Fri Sep 29, 2006 11:30 am

Thanks, Gary. I was actually thinking "cellulose acetate", but that would have been wrong, too!

It's great to have an organic chemist in the house!

And it is the nitric acid that eats into everything.

beatlefreak · Post by **beatlefreak** » Mon Oct 02, 2006 7:03 pm

There's an excellent article on this very subject in the October issue of Vintage Guitar in 'Dave's Guitar Rx' on page 100. The only thing you can do is is get rid of the offending plastic.