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Old 01-05-2019, 03:13 PM
Lynn Read Lynn Read is offline
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Join Date: Aug 2008
Location: Portland, OR
Posts: 17
Lynn Read is on a distinguished road
I wanted to share the results from my tests melting Phosphate white.

I am working with Spruce Pine Batch W/er87. Melting in an electric furnace with 50 lbs test melts at 2350 for about 4 hour melt, drop to 1900 for 4 hour soak and back up to working at 2130. That can be adjusted I think.

First tow melts with STPP Molecular FormulaNa5O10P3 Did not have any visible opalescence. My third test worked but was not an ideal system.

50 lbs SP batch
907 g STPP

Image #1 Full reheat - After a started Bubble is allowed to cool, the second gather and a full reheat caused the density to develop.

Image #2 Fresh gather cast and pressed. no reheat

Image #3 Spot heat with hot torch. My favorite so far

Image #4 started bubble allowed to cool and gathered with a limited reheat

Image #5 Spot heating with Torch on cast glass.

Amazing the variation heat has on this glass.

Does anyone have recommendations on getting the phosphate to strike on the cool down vs the reheat? I want to use this is casting /press molding but I do not have the option of reheating my castings without loosing the shape and texture. See image 5 for best results.
Attached Images
File Type: jpg Full Reheat.jpg (26.6 KB, 59 views)
File Type: jpg Fresh gather casting and pressed, no reheats.jpg (29.4 KB, 53 views)
File Type: jpg Spot heats with hot torch.jpg (31.5 KB, 52 views)
File Type: jpg Gather over and limited reheat.jpg (26.5 KB, 49 views)
File Type: jpg Spot heat on cast glass.jpg (25.6 KB, 54 views)
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