kiln wash and bisque mold

[wynpotter]

Hi folks, I'm a potter that is looking to getting into slump glass.I plan to make some bisque flat rectangular trays.
My kiln wash for my pottery is 1/3 alumina hydrate, 1/3 kaolin clay, 1/3 350 mesh silica. Should i leave out the silica and go 50/50 kaolin/alumina hydrate?
I'm looking to fuse a base slab of glass with both random colored glass geometric shapes as well as painting on some enamel frits.
How much cleanup is usually there for the back of the slump pieces after firing.
thanks for any thought.
Wyndham

[Brad Walker]

Just alumina hydrate and kaolin, 50/50. No silica needed or desired. Mix with 4 to 5 parts water.

At slumping temperatures (under 1300F), you shouldn't have any kiln wash stuck to the glass.

You can also use 80% alumina hydrate/20% kaolin for a wash that is single use but is even less likely to stick, even at fusing temps.

[wynpotter]

Thanks Brad. 80/20 sounds good
Wyndham