Flow slab melt inclusions

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Wrangell
Posts: 12
Joined: Fri Apr 14, 2017 9:07 pm

Flow slab melt inclusions

Post by Wrangell »

Hi,

New to forum and new to glass fusing (4 months)

Did a flow slab last weekend and have a few questions on what the results point to.

We are using a Evenheat Studio 24 kiln. Sides and top lid elements.

The glass we used for the flow slab is Bullseye as follows
Citronelle Opalescent 000221-0030-F
Cobalt Blue Opalescent 000114-0030-F
Driftwood Grey Opalescent 000132-030-F

The flow slab technique and size is identical to the Bullseye lesson video for flow slabs using strips cut and put into two stacks. The pattern dam was 17cm x 25cm x 1.9. The strips were cut into 1-1/2" wide and varied in length from 5-1/2" to 6-3/4" for a total of 2074 grams of glass. The stacks favored one side of the short side of the dam but still about 1" away from the closest side.

Schedule is as follows
300F 1225F :45
600F 1525F 1:30
AFAP 900F 3:00
45F 800F :01
81F 700F :01
AFAP 70F :01

Anyway, everything turned out really good with a few tiny surface bubbles that were not my concern. Cut the bars up into 3/8" thick strips on the wet saw and have some inclusions a few of the bars. If you look at the spots, most don't travel into the next slice so I'm assuming they are not that large. Probing them with a tool they are less than 1mm in depth.

What we would like to know is if these will melt out and not be an issue when we fuse everything together. This is our first try at pattern bars and have only been kiln working for a short time.

We are assuming that to do the fuse of the bars that we use the annealing table on B.E site. Would have to look at the video again and see what the fuse temp should end up being at 3/8" thickness

Any help on these questions would be greatly appreciated.

Thanks
pattern bar 2 resized.jpg
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pattern bar resized.jpg
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Sharol
Posts: 123
Joined: Sun Mar 05, 2006 2:45 pm
Location: Tennessee

Re: Flow slab melt inclusions

Post by Sharol »

Hi Wragell.

By "inclusions", you're referring to the bubble holes you found upon slicing the slab? Some of those holes may fill in when refired, but some may not. It depends upon how big/deep they are and how hot you fire the piece.

I've had good luck just filling the void with clear fine or medium frit. Mound it up a bit. You will want to use an annealing schedule that is appropriate for the thickness of the final layup. I usually go a little more slowly though when firing pattern bar slices.

They look great, BTW. Very spring-like :)

Sharol
Wrangell
Posts: 12
Joined: Fri Apr 14, 2017 9:07 pm

Re: Flow slab melt inclusions

Post by Wrangell »

Thanks for the help Sharol.

Yeah, the inclusions appear to be small bubbles but don't seem deep. I'll try your advice on adding clear fine frit to these areas.

Will use the B.E chart for annealing process. Their video indicates firing to 1490F for 20 minutes but I need to do a little more research on this. I saw cut the segments 3/8" wide so the piece is going to be 3/8" thick when done. Haven't fired anything this thickness yet.

Thanks again for your help.
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