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What is the sticky liquid that settles around old celluloid ?

We all know that old celluloid can decompose , and it tends to take out metal parts nearby . I have an old Gretsch duo jet in for work with crumbling binding , the 3 way switches ( 3 of them) have liquid condensed on them which I suspect will eat them away , pots and screws are rusty too . I think this is some kind of acid , any ideas ? and what to do ? Thanks .

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pictures please?

I'm with Kerry. We need pic's.

Vintage Gretch's are especially notorious for having crumbling binding and the problems associated with it.

The effect you are experiencing is caused by off gassing of the chemicals used in the plastic binding. There is no way to save the binding. Furthermore, without removing/replacing the original binding, any new hardware you install will quickly suffer an identical fate.

If your customer is wanting to get the guitar back to original spec's, prepare to replace, NOT repair, any corroded parts.  IF you're not experienced with disassembling & reassembling  the leaf style switches for cleaning & restoration, you're much better off replacing them with new parts.

I hope the pic's aren't as bad as what you've described, but you'd better prepare your customer for the cost of rebinding the instrument.

Good luck, Len. :)

Celluloid Nitrate is nitrocellulose, nitrogen, and camphor (C10H16O).  When it decomposes it combines with water vapor in the air to create nitric acid (HNO3). Nitric Acid is a powerful oxidizing agent. We know that decomposing celluloid is combustible. As it turns out, nitric acid is the primary component used to synthesize nitroglycerin and TNT. This is what eats at metals. The rest of the goo is just celluloid rendered unstable. Fully decomposed it will turn into a rust-like powder, hence the rusty streaks on old celluloid.

And, if that's not enough, some of that old celluloid is cellulose acetate, and as it decomposes it can get positively wet and drippy with acetic acid.

So why do we use celluloid at all?  Because we like to suffer. . .

Thanks for that info , my camera has died so no pics , several leaves had broken off one switch and that wet acid was everywhere but it seems to wash off with water . I tried to stabilise the binding with thin CA but it just got more crumbly .Owner doesnt want to rebind yet .

Hi again, Len.

Given that your customer doesn't wish to address the true cause of the problem, you're in quite a dilemma.

If I were in your shoes, I'd bow out of the repair if rebinding is not approved.

Alternately, I'd offer no guarantee of parts or labor if any any work is agreed upon & performed without rebinding.  The situation WILL repeat itself and any work you do to the instrument will/may suffer the same fate.

Best of luck in proceeding with this case. :)

I'm with Paul. If rebinding WAS to be part of this fix , and they said no, I would hand the guitar back. If not and you do the wirk, this is one of those things that could follow you for a decade or two. 

Perhaps you can get the customer to let you do some cleaning and prevention by cleaning the switches with water and baking soda to neutralize the acidic condensation.  After cleaning the mixture off with warm water you might spray the switches with alcohol to dry them before using DeOxit.  Brushing the binding with this mixture might also slow the binding's decomposition and have the virtue of being harmless to the finish. I wouldn't rub the finish with dry baking soda since it is a mild abrasive.

Robbie , thats exactly what I did , but I didnt think to try the soda on the binding , to clear up the situation , this guitar was found in a country shed and had been in its case for years , my customer will be delighted that it works , and may decide to re-bind . I think it may be a  rare duo jet as it has active preamp which can be switched in by the 3rd  3 way (lower bout).

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