Hello, looking for some tips on how to anticipate fuse shrinkage while fusing Bullseye glass. All thoughts/comments welcome!
I'm getting ready to make 2 fused pieces. The final sizes of the pieces must be 48,1 x 33 cm (18.9 x 13 inches) and 58,1 x 32,9 cm (22.9 x 13 inches), give or take a smidge. These fused panels will fit into windows in an apartment interior, in the bathroom door and the bedroom door.
The basis glass sheet is 3 mm thick and then there will be design-flowers built up on that but not overall on the glass. Some of the final piece will be 3mm thick, in some places 5-6 mm thick. I intend to leave the edges of the glass free of materials so that there's not an issue with placement.
I've done some small tests in advance to see how I want to make the design and at what temperature. The final pieces will be fired at 785 C.
Of the two tests I've done at 785 C:
- for the first test the glass size pre-firing was 18,2 x 16,7 cm and the size post-firing was 18 x 16,5 cm
- for the second test the glass size pre-firing was 18,3 x 14,4 cm and the size post-firing was 18 x 14,2 cm
Is there any way I can reliably scale up the sizes so that I get just the right amount of shrinkage ?
Thanks in advance!
kind regards,
Lisa
Bullseye glass shrinkage after fusing
Moderators: Brad Walker, Tony Smith
-
- Posts: 381
- Joined: Sun Mar 09, 2003 9:09 pm
- Location: Ontario
Re: Bullseye glass shrinkage after fusing
Shrinkage is based on volume of glass, not manufacturer... If the glass is not a uniform 2 layers thick you will get shrinkage! You have a few factors to deal with eg: top temp, top temp. hold time, amount and location of second layer design...... Your safest bet is to fire oversize and grind/polish to size.
"The Glassman"
Re: Bullseye glass shrinkage after fusing
Thanks Don!
What about making it significantly larger and then cutting to size? Any thoughts?
What about making it significantly larger and then cutting to size? Any thoughts?
-
- Posts: 381
- Joined: Sun Mar 09, 2003 9:09 pm
- Location: Ontario
Re: Bullseye glass shrinkage after fusing
Yes that would also work if you don't have a WBS. An extra 1/2"of base glass on each of the 4 sides would be easy to score and remove.
"The Glassman"