Question about fusing on/in bisque

Valerie · Post by **Valerie** » Tue Mar 11, 2003 10:40 pm

I have taken my 90 coe scrap and cut it up in very small pieces with the mosaic cutters and I would like to put it in a shallow bique plate mold. If I ramp up very slowly with a hold time at 1250/1300 could this work?
I have washed and air dried my scrap, and kiln washed my mold.
Thanks in advance for any and all advice Valerie

Barbara Muth · Post by **Barbara Muth** » Tue Mar 11, 2003 10:58 pm

Valerie, you need to fuse the scraps together before you slump.

Barbara

Valerie · Post by **Valerie** » Tue Mar 11, 2003 11:16 pm

I guess I was not clear on what I wanted ...I want to fuse the scraps in the bisque mold ...like a casting? Is that the correct term?
I did not have very good luck with fiber board so I thought I could use the bisque plate mold to "fuse" my scraps in

Brad Walker · Post by **Brad Walker** » Tue Mar 11, 2003 11:29 pm

If you want your scraps to fuse together in the bottom of your mold, then you will need to fire higher than 1250/1300 F. Try around 1450/1500 F (800C). This should work, but make sure you have a good coat of kiln wash on your mold.

Lauri Levanto · Post by **Lauri Levanto** » Wed Mar 12, 2003 4:33 am

I do almost all my work in frit casting in bisquit mold.
MOst pieces are shallow reliefs, essentially flat.

As Brad said some 800-840 C is a proper temperature,
but ramp up slowly at two stages

570-600 C, the quarz inversion point at 573 C is quite a stress for a large flat mold.

650-700 C spend at least one hour to prevent the trapped air
to form bulges below the melted surface.

lauri
P.s. I kilnwash my molds before bisquit firing, so the 1st
layer of kilnwash is absorbed by the clay.

In subsequent firings in these temps you need a new
coat of kilnwash

Valerie · Post by **Valerie** » Wed Mar 12, 2003 7:47 am

Thanks everyone for their input. I knew I had to go slow from my previous attempt. I just thought holding longer at a lower temp would take the stress off the mold. I will put an extra layer of wash on before attempting this.