WarmGlass.com

Hi,

I just ordered some fiber paper and have a question about firing it for use. I know the tutorial says to vent the kiln. Does this mean that all I need to do is crack the kiln door while firing it up? Do I wait until the kiln reaches a certain temp before venting, or should the door be open a bit the whole time? I appreciate any help!

Thanks,
Marie

Marie,

I usually burn out the binder before I use my paper. I do this because the smoke from the binder leaves a scum on the glass especially opaques. It doesnt seem to matter whether I vent the kiln during the firing or not, the scum seems to remain. The only way to get rid of the scum is to sand blast it off.


I goto 1100 and hold for 10 minutes.
If I am using Irrid (it doesnt stick to the irrid surface) face down to get texture and dont care what the back look like I dont burn it out.

Michael McNerney wrote:Marie,

I usually burn out the binder before I use my paper. I do this because the smoke from the binder leaves a scum on the glass especially opaques. It doesnt seem to matter whether I vent the kiln during the firing or not, the scum seems to remain. The only way to get rid of the scum is to sand blast it off.


I goto 1100 and hold for 10 minutes.
If I am using Irrid (it doesnt stick to the irrid surface) face down to get texture and dont care what the back look like I dont burn it out.

Michael

I too prefire my fiber paper most of the time. I have found that working with float glass that pieces of glass 12" or under don't get effected by the burning carbon as it has ways to get out. It can get trapped and scum up larger pieces.

I recommend prefiring the paper to the process temp that you plan to work at. That way there are no surprises. I don't usually bother to vent if the kiln is empty. I do leave the shop during the burnout firing though.

If you were going to vent with the glass in the kiln, you should be able to close the lid all the way around 900 or 1000ºF. The lid only needs to be a cracked open to vent OK. The smell will be pretty much gone by then.

I do not prefire fiber paper, and have always wondered why people do. When I kiln carve I use transparent/cathedral glass and these are commonly iridized. I suspect the opaque glasses would be more susceptible to devit due to the burning off of the binders. I was surprised that Bert has problems with scum developing on float glass.

I guess my point is that you might need to prefire for some glass types and not others. Anything we can do to reduce firing time would be a benefit.

Cheers,

Bob

Bob wrote:I do not prefire fiber paper, and have always wondered why people do. When I kiln carve I use transparent/cathedral glass and these are commonly iridized. I suspect the opaque glasses would be more susceptible to devit due to the burning off of the binders. I was surprised that Bert has problems with scum developing on float glass.

I guess my point is that you might need to prefire for some glass types and not others. Anything we can do to reduce firing time would be a benefit.

Cheers,

Bob

Bob

My problem is one of scale. The carbon can get trapped in the center of a piece 40" wide and 7' long... For a long time I worked without prefiring in my 20" x 40" kiln. WHen I went to the larger kiln I got the black scum thing.

Marie,

I have a small kiln and forgot to prefire the 110J fiber paper I bought on this web site. The cabochons I was firing got a gray ring around the outer edge. Of course I had several white ones in that firing. Had to grind all the edges and refire. From that experience I'm not sure the size of what you're firing matters. Or maybe the 110J, being very thick, is what made the difference?

Sharon

The binder appears to be a bit heavier in 110-J than in regular fiber paper. This is probably because the 110 is denser (that's probably one reason it lasts longer). I have to prefire 110 to around 1400F to make certain it all burns out.

I tend to prefire any paper (other than thinfire or thin strips I'm using to line a dam), especially with opaques. Better safe than sorry.

I want to thank everyone for their replies. I see some experimenting needs to be done. Now I can't wait for my order to arrive so that I can play.

Again, thank you,
Marie