Scott, What you refer to as "Celluloid", may not be what we in this "colony" know as celluloid! (Although we both speak English, there tis a difference, ya know, mate. <G>)The first form of plastic was celluloid. It was EXTREMELY flammable. This is what was used on the pre-ivory-ban key fronts. The more modern plastic that is referred to as "Ivorine", is not as flammable and is available from one supplier, in 2 thicknesses, (.050" & .060"). This is available from Schaff. IMHO the use of "Moulded" keytop material is substandard in many ways, although there are those, out there, who have learned to do a credible job. (flame suit firmly zipped up w/eye protection, ear protection and vapor barriers armed.<G>) The Ivorine will be a better keytop, if trimmed properly and of course properly glue with the appropriate glue, which is PVC-E. Those who use the caustic "Contact Cement" get good results, as well. But, there is a down-side to using Contact Cement: It degrades and loses it's adhesion after about 20 years. This I know from personal experience. There is a third glue that is made from Ivorine trimmings and Acetone. But again, it has it's down-side. The darn stuff sticks too well, softens the plastic too much, which shows every minute imperfection in the under-layment surface. Hence the key tops get "wavy". The machine, of record, for trimming Ivorine, is the "Oslund" System. This machine is difficult to use, archaic and difficult to keep in adjustment. Much hand filing is always necessary with Ivorine and this system. I know this is why most prefer the "moulded" tops. "Moulded" tops would be ok IF all keys were dimensionally the same. (NOT!!!) Best Regards, Joe Garrett, RPT, (Oregon)
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