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Dull surface after firing my work.

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Dull surface after firing my work.

Postby Ronnyboer » Wed Aug 09, 2017 10:52 pm

I am having problems with some of my work.

After I have done some coldwork, either with my grinder or saw, and then firing the piece, i get a dull edge on the piece which is clearly the area where i have done the cold work!!

I have tried heating it up slower.. a longer hold time (worried about devitrification) at the top. Changing the top temperature from 790 up to 820 degrees C. I have followed the advice to keep the piece wet after cold work, and then cleainng it with nail brush.. But the results stay the same. You can see the edge of the cold work.

Can anybody please advice me on how to solve this issue?

Fusion greetings

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Re: Dull surface after firing my work.

Postby marykaynitchie » Thu Aug 10, 2017 9:26 am

Hi Ronny,

When firing a ground edge, it is critical to completely clean the edge with a brush, to get any ground particles washed away--otherwise, those particles will seed devitrification. It's best to do this washing immediately after grinding, while everything is still wet, and then clean the edge again immediately before firing.

Grinding to a finer finish will also help discourage devitrification on ground edges.

I hope that helps!

Mary Kay
Mary Kay Nitchie
Bullseye Glass Co.

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