raking rage

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slats
Posts: 110
Joined: Thu Sep 04, 2003 9:19 pm

raking rage

Post by slats »

Three successful raking......until....latest.....three big bubbles leaving big holes. Why? First, put down thin fire paper....the pieces of clear glass (I did not use a solid piece but have done this before with no problems) to cover shelf, then lined up glass rods and BE strips of glass and fired away using Patty Grey's combing schedule. Have always gotten good results following the same pattern but this time big bubbles and I do not understand why? :roll: Help appreciated...........
charlie
Posts: 961
Joined: Mon Mar 10, 2003 3:08 pm

Post by charlie »

were the bubbles there when you were doing the raking, before, or after?

all bubbles come from trapped air. you just have to figure out when the air got introduced, and allow it to come out somewhere else sideways rather than through the top.
slats
Posts: 110
Joined: Thu Sep 04, 2003 9:19 pm

raking

Post by slats »

The bubbles or holes inch wide were there before I raked. Raked through them and managed to close them but the fire paper came through..now looks like devit. Used the same method before (large pieces of clear on bottom and rods on top) and this never happened?
Bert Weiss
Posts: 2339
Joined: Tue Mar 11, 2003 12:06 am
Location: Chatham NH
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Post by Bert Weiss »

Glass thinner than 1/4" is particluarly prone to killer bubbles. Thicker is better. 1700 is a very unforgiving temp for glass. Everything must be just so for it to survive the experience.
Bert

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