SilkeMat is a non-carcinogenic kiln forming blanket - exclusively at Creative Glass Guild in the UK. Use it to create re-useable forms for slumping glass, use the rigizider (sold separately) to give structure and the ability to create repeat slumps of the same forms, as it is a non-carcinogenic fibre, it can be cut and handled with minimal concern.
It is recommended to prefire SilkeMat to 788°C (1450F) for 15-20 min to burn out any moisture. There are no organics to burn off, but moisture and a small amount of residual oil from the rollers may be evident. Vent your kiln accordingly. If rigidizing you may skip the pre-fire instructions.
SilkeMat will shrink slightly on the first firing, but will not change upon subsequent firings. Once fired, you will notice that SilkeMat becomes slightly stiffer. This also allows it to hold a form longer. SilkeMat can be laser-cut and/or hand cut for kiln carving projects. The fabric cuts cleanly for a crisp edge and can be fired multiple times with no degeneration.
SilkeMat may be rigidized with SilkeMat Rigidizer, but care should be taken when sanding down a flat piece, using a good dust mask. A rigidized board may be coated with kilnwash or a high-quality boron nitride spray to avoid any sticking issue due to the rigidizer.
SilkeMat may be molded without rigidizing - it has a memory for soft forming and will hold that form for many subsequent firings.
Float Glass has not been found to stick to SilkeMat at normal temperatures, even with multiple firings. However, softer glasses (COE 90 & 96) & opaque glasses are more stubborn at full-fuse temperatures, although residual fibers can be removed with a brush. Coating the unrigidized blanket with boron nitride has not appeared to prevent sticking, so use caution accordingly. However, a light dusting of dry kilnwash on the pre-fired SilkeMat has been an effective separator when being used as a firing surface.
When using SilkeMat for slumping molds, it has not been necessary to do any preparation other than prefiring. You can shape and prefire at the same time. And all glasses tested, released smoothly with no clouding at slumping temperatures even when the interior has been left unrigidized.
If rigidizing and using as a pot melt or vitrigraph mold, firing to 871°C (1600F) for an hour has been sufficient to create a nice melt, and the residual glass usually pops out with little to no damage to the mould. The ¼” thickness is quite sufficient for all applications above with little, if any, degradation upon multiple firings.
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