Celluloid issue, bowlback inlay

[Richard500]

I know I’ve asked before, but there were no opinions. I’ve got a few bowlbacks from the celluloid inlay era and am restoring one now. Its inlay (below the strings) had curled a bit, but is one piece of faux tortie, 1mm thick. Everything I can find on the web indicates that celluloid ages very badly and becomes even touchier with respect to fire. There seems to be no chemical means to ‘fireproof’ it. So I ordered some vinyl pickguard material to replace it, but the thickness was incorrect, and the pattern gross. What to do?
Do restorers generally replace these ‘guncotton’ items for looks or safety, and do collectors or museums take any precautions other than isolation?
There’s far more to worry about than exploding mandolins these days, but....

[rcc56]

A repairman's point of view:

Celluloid is no more and no less flammable than it was 100 years ago.

In most cases it takes many decades for the stuff to deteriorate to the point where it emits gasses, causing a hazard for finishes, metal parts, etc.
It shrinks much more slowly than the "Boltaron" [ABS??] material that Martin started using in the later '60's.

Their are many thousands of decades-old instruments containing celluloid that are still in very good shape.
Yes, some, but not all of the 80 to 100 year old Gibson pickguards and bindings have deteriorated to the point where they must be replaced. Some will still be ok many years from now.

I have heard one rumor, and only one, of spontaneous combustion of celluloid.
Celluloid shavings are indeed very combustible, and should be removed from a workbench immediately.

Celluloid seems to last a long time if it's been sealed with nitro.

I'm going to continue using it as long as it is available. And curse the HazMat shipping surcharge. It seems strange that law requires the surcharge to be applied to celluloid stock, but not to most solvent based finishing products, which are probably more combustible than celluloid.

I did run into one new batch of really cheap, thin celluloid that I did not trust. If I remember correctly, the stuff came to be second-hand from Johnson. The stuff was giving off quite a bit of odor just sitting undisturbed. Normally, the stuff has no noticeable odor unless you scrape, sand, or cut it. So I discarded it.

[pops1]

I agree with rcc56 . The only time I would worry is if you have it shut in a case for a long period of time. If you are going to play it I wouldn't worry. My '22 Gibson has the original pickguard and it is in great shape.

[Jim Garber]

I had an old guitar that needed a replacement pickguard but had my luthier replace it with a Tortis (made by John Greven) one that not only was not celluloid but looked better than anything that was available. I believe that Luthier's Mercantile carries it but their photos look odd to me. I might call to see if they have different patterns. When i had my guitar restored they showed a variety.

StewMac has their version, Tortoloid, developed and made by our own Mario Proulx. I believe that both these products are similar to (or may actually be) casein pick material so you have to be a little careful cutting it. What is nice is that you may be able to match the old pickguard on the mandolin you are working on.