KAG wrote:...I'm considering fiber board...but wanted to know pros and cons first. I've heard that you always have to fire on thin fire. Should I purchase 1" or 2" thick? Does it warp/trap air? How long should it last? I've read that you get better annealing on fiber board.
Needingfeedbackgirl
I have a 30 x 60 inch kiln and have a 2" fiber shelf called Magnaform. It's an extruded Unifrax fiber product and is rigidized for you. I always use paper as an insurance policy. Most tested compatible opals will stick and when it pulls up the wash, it can tear up the shelf. Some transparent can stick, so I just always use paper unless I'm firing float or window glass. That doesn't seem to stick...so no need for paper. I don 't have any experience with any other types of glasses...so nothing to add there.
It is fiber and therefore pourous, so one really nice advantage is that it never traps air and bubble trubble aint a problem. Again, it's fiber, or specifically RCF (refractory ceramic fiber). My understanding is that RCF's are not carcinogenic, but considered a nusiance dust that cause respiratory irritation, but doesn't lodge in the tissues like asbestos or silica, so isn't currently labeled as a health hazard at
certain levels of exposure.
They used to consider asbestos safe too...so I wouldn't take any chances and simply wear a respirator when cutting or sanding, vacuuming the material. Use good vetilation too and clean up with water and use a hepa filtered vacuum.
The thicker the board the less it will warp, but it will warp.
The Magnaform shelf should last indefinitely if you care for it kindly (the thinner softer fiberboards may be more perishable). I carefully sand off the kiln wash with fabricut then vacuum it out before each new application. I try not to sand down to the fiber, but just take off the top layer or so of primer. I wash it with new primer every full fuse firing to make sure that if my paper fails I have a healthy layer of clean wash in place. This is to protect my investment in the shelf. The thinfire I use shrinks and tears under larger pieces, so I want to be sure my shelf is covered with a layer of wash.
Better Annealing? I expect you fire according to the thickness of the glass and the insulating and heating properties of your kiln. I don't think that a fiber shelf will change how well you anneal your glass, but it might require an adjustment to your schedules if you switch.
Happy shelf hunting.
. Inside dimensions are 28" x 28" sq., but the shelf that came with it was only 21". Naturally, I want to take advantage of all the room available, but having trouble finding (google search) a larger 24" shelf. Do they make shelves larger than 21"?
