@comments2 thanks Jennifer. I used 2-3shelfs all the time but will try a little slower ramp up and see. I will try fusing them back together. How many times can glass be melted?

@Laceyboo I would not use granite. Have you ever put any rocks in a fire? they explode or at least crack most of the time and granite is afterall a rock

Please Help!!! I have been slumping bottles in my kiln for the past 2 years and last year started to fuse glass. I have been very successful being it is a large pottery kiln. I slumped a fused coe 90 piece a couple of weeks ago along with some specialty bottles a friend needed. everything great. I fused some very large pieces of glass art and they all came out great. I went to slump 3 large pieces of already fused glass artwork, one on 1"fiberboar with a whole cut out , one on a stainless vase cylinder and one on a Ceramic ring that I had used before. I ramped up the kiln at 500 degrees per hour and once it reached 1300 degrees I cooled to 980 and closed back up and soaked and then cooled. when I opened the kiln to cool the first time I thought the top piece already looked broken. all three levels were broken. Too hot on ramp up when glass is already fused? Bummed Jewelry has come out great and because I have all the pottery supplies I can make countless shapes to slump on and into. I really thought I ramped up at 500 degrees the last time but may have done it at 400 degrees I really did not think that would make a difference.