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I have a piece of fiber board that has been cut to use as a shelf in my kiln. I haven't used it yet or used the rigidizer on it. Do I need to fire it before rigidizer or just spray away and go? What temp do i need to go to and for how long?
I've finally gotten an electrician to wire up my new kiln and I'm dieing to use it but don't want to run the fiber board
Thanks for any help you can give me
Diane

I usually put the ridgidizer on first then do the burn out. You should let the ridgidizer air dry first though. Mine usually take a few days. Once you've done that you need to use kiln wash or fiber paper as a separator.

Amy

Diane wrote:I have a piece of fiber board that has been cut to use as a shelf in my kiln. I haven't used it yet or used the rigidizer on it. Do I need to fire it before rigidizer or just spray away and go? What temp do i need to go to and for how long?
I've finally gotten an electrician to wire up my new kiln and I'm dieing to use it but don't want to run the fiber board
Thanks for any help you can give me
Diane

Hi Diane

I use an HD board as a shelf in my Evenheat. I use it as is, no rigidizer, no kiln wash. I have fired straight on it, no problems. But, the finish on the bottom it leaves is a bit rough, so I usually use thinfire.

I'm not sure I understand the rationale of using rigidizer, maybe someone can enlighten me?

About burnout, I recently talked to holly at Denver Kilns about a new kiln that uses HD board as a shelf and she suggested burning the board out by going 600dph to 600, hold for an hour, then go 600 dph to 1200, hold for an hour.

Lisa

I ridgidize my fiber boards for a couple of reasons. First is to make them a bit more durable. I'm kinda rough on my shelves cause I have to dam my work so much with bricks that ridgidizing helps the life of the shelf a bit. I also fire to high temps. so it helps here too.

When I burn out a shelf I go say AFAP to 1500F.

Amy

Lisa Allen wrote:

Diane wrote:I have a piece of fiber board that has been cut to use as a shelf in my kiln. I haven't used it yet or used the rigidizer on it. Do I need to fire it before rigidizer or just spray away and go? What temp do i need to go to and for how long?
I've finally gotten an electrician to wire up my new kiln and I'm dieing to use it but don't want to run the fiber board
Thanks for any help you can give me
Diane

About burnout, I recently talked to holly at Denver Kilns about a new kiln that uses HD board as a shelf and she suggested burning the board out by going 600dph to 600, hold for an hour, then go 600 dph to 1200, hold for an hour.

Lisa

I don't rigidize either; & use regular fiber paper w/dry kiln wash sifted and smoothed with a dry haik brush - some texture yet smooth.

I can see the hold at 600F - that's where the most smoke/fumes seem to be.

Don't forget to vent!

Happy big cooking, Diane!

Jo

Thanks for the info guys. I got ahold of Marty at CDV this afternoon and he said I should lightly sand the board then fire the at 500dph to 1450 hold 15 and off.
then spray the board and fire again with the same schedule. He said this will make it smoother and stronger.
I can't wait to finally play with my HOT new friend "Kenny"
Diane

Rigidizing is more a safety issue first and a durability issue second. Fiberboard is not nice stuff for your lungs. Check out this web site:

http://www.unifrax.com/Products

Click on Boards, then click on Duraboard products then Duraboard HD and then click on MSDS. Read it carefully!

Using rigidizer lessens your exposure to fibers by binding them on the surface. If you use a respirator when you wash these shelves, that will help. On fiber boards you should ALWAYS use your respirator. Not for the kilnwash (many, many posts on this, kinwash is a nusance dust, not a prolonged health hazard). Fiberboard is a carcinogenin.

Your lungs.

Your choice.

I rigidize.

Phil

Great points Phil.

I knew there was something else, but forgot what. I kind of just automatically do it, ya know.

Amy