Bowl Slump

[John]

Hi all,
Well after some exaustive testing, I have finally said goodbye to devit on my 10mm clear.
I have done some platters on fibre board and they have come out excellent. (I am slumping on a bed of sand.)Also some bowl blanks have gone in too.
Went off to the local provider of good quality stainless cooking accessories and got some bowls. I kiln washed them up then put in the blanks...... today when I got home from work they surfaced 1 was good the other two did not fall to well.

5hrs to 640
soak at 640 for 2hrs
then set annealing.
After some research into the archives I have decided put the two back in one doing a drape one in the bowl, they are steep sided bowls.

set the controller for

5 hrs to 700
soak at 700 for 1 hr 45mins.

Hows that sound?any ideas???

John.

[Bert Weiss]

Hi all,
Well after some exaustive testing, I have finally said goodbye to devit on my 10mm clear.
I have done some platters on fibre board and they have come out excellent. (I am slumping on a bed of sand.)Also some bowl blanks have gone in too.
Went off to the local provider of good quality stainless cooking accessories and got some bowls. I kiln washed them up then put in the blanks...... today when I got home from work they surfaced 1 was good the other two did not fall to well.

5hrs to 640
soak at 640 for 2hrs
then set annealing.
After some research into the archives I have decided put the two back in one doing a drape one in the bowl, they are steep sided bowls.

set the controller for

5 hrs to 700
soak at 700 for 1 hr 45mins.

Hows that sound?any ideas???

John.

John

You can meticulously check that the glass and bowl are level. If the heat is even that is all you can do that I know of, short of one technique, the Brock shuffle. Brock wears kevlar gloves and removes the mold when it is hot and quickly repositions the glass to his liking, then replaces it in the kiln. If I got that wrong, I'm sure he'll chime in.

Sometimes I like to promote a quick uneven slump which can be interesting.

I don't generally slumo in mixing bowls. I paid the big bucks and bought spun stainless molds from Fusion HQ (a board sponsor now). They are shaped in a more slump friendly way. My molds are rugged and well designed and made. I can do 10 16" flared bowls in one firing. Some slump more evenly than others. I haven't carefully leveled the glass though.