Kiln wash floor of glass kiln?

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cherylka
Posts: 26
Joined: Fri Oct 10, 2003 10:45 pm

Kiln wash floor of glass kiln?

Post by cherylka »

I've searched for an answer, but can't find it. Sorry if this topic has been raised before.
I've been fusing in my ceramic kilns for 12 years. I just bought a Nabertherm Glass kiln. As you may know, it is not a small investment.
I've been reading posts in favor of kiln washing the floor of glass kilns. However, in ceramic kilns, old kiln was becomes hard and flakes off on everything.

Is this a concern with my glass kiln?

Do you kiln wash the floor of your kiln?

Thanks for your help!
Bert Weiss
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Location: Chatham NH
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Re: Kiln wash floor of glass kiln?

Post by Bert Weiss »

If glass should fall on the brick, it will stick to the brick and mess up your surface. You don't want that to happen. You can either kilnwash it, or cover it with fiber blanket or fiber board. I cover my floor with 1/4" fiber blanket, and fire directly on the blanket, which is dusted with alumina hydrate.
Bert

Bert Weiss Art Glass*
http://www.customartglass.com
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cherylka
Posts: 26
Joined: Fri Oct 10, 2003 10:45 pm

Re: Kiln wash floor of glass kiln?

Post by cherylka »

Thanks, Bert.
I have tons of fiber blanket, but I don't know what Alumina Hydrate is, or where to get it. Can I sprinkle glass primer on the fiber instead?

C
vblue
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Joined: Sun Mar 09, 2003 11:05 pm
Location: Texas

Re: Kiln wash floor of glass kiln?

Post by vblue »

I just taught a class where a students project slipped during firing and was too close to the edge of the shelf. If the shelf sides and kiln bottom had not been kiln washed, the glass would have stuck.
Bert Weiss
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Location: Chatham NH
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Re: Kiln wash floor of glass kiln?

Post by Bert Weiss »

cherylka wrote:Thanks, Bert.
I have tons of fiber blanket, but I don't know what Alumina Hydrate is, or where to get it. Can I sprinkle glass primer on the fiber instead?

C
Many Kilnwashes are made using a 50/50 mixture of alumina hydrate and EPK. The reason I prefer alumina to kilnwash is that the EPK has silica in it and goes through the quartz inversion. After this happens, it sometimes leaves a scum on the glass that is difficult to remove. The EPK is used as a binder to hold the wash on the shelf. So, I prefer powdering my blanket with just alumina hydrate. The alumina hydrate they carry at my local pottery supply is not ground as finely as the alumina used by Bullseye to make their kilnwash. I had to search far and wide to get a finer grade product. It is available. One brand is JM Huber Alumina Trihydrate SB432. There are others.
Bert

Bert Weiss Art Glass*
http://www.customartglass.com
Furniture Lighting Sculpture Tableware
Architectural Commissions
Alexis Dinno
Posts: 57
Joined: Sun Dec 13, 2009 9:35 pm

Re: Kiln wash floor of glass kiln?

Post by Alexis Dinno »

cherylka wrote:However, in ceramic kilns, old kiln was becomes hard and flakes off on everything.
Kiln wash on the floor of your kiln will not get on anything except the floor of the kiln. I do kiln wash the floor of my kiln (quite thick). When rejecta from thinfire paper, fiber paper, kiln washed furniture, glass bits etc. accumulate on the floor, I sweep it out. Easy! Done.
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