Still pretty new to kiln work at the moment, but after reading through this Tip Sheet a few times I'm beginning to wonder if the actual slumping temperature has been completely missed out in the tables on the last couple of pages.
Has anyone else noticed this?
I'm not going mad am I?
I'm assuming you're looking at the technotes from the Bullseye Glass website (they were updated late last year, so you could possibly be looking at an old one somewhere else?)
Looks okay to me - slumping occurs at quite low temperatures - once you've done your fusing (so you don't need a bubble squeeze or anything) first, you don't need to go so high to slump.
See technotes 4 for a guideline of what happens at each temperature zone.
Listed on the Bullseye site as - 008077 - TipSheet 7: Platemaking (revised 2007-10-25)
That refers to a slump @ 663C
Checked the Tech Sheet mentioned and that gives a range of 593-704C. Thank you.
So, looks like I am going mad, lol
It's quite surprising, isn't it, just how low a temperature glass will slump at.
I have usually slumped at higher temperatures, but looking at this, it avoids going into the devitrificatin zone.
I tried my first slump last night, but with some random off-cuts that I picked up cheap for messing around with.
Had to fuse form a square of it first, but it didn't start to slump until 720C. Think the COE was around 96 though, so could explain the higher temp required as it wasn't Bullseye.
There's another in the kiln at the moment that is, so anxiously waiting for the numbers to rise ;D