Thread: ring tests
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Old 10-25-2019, 02:38 PM
Josh Bernbaum Josh Bernbaum is offline
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So on my latest phosphate white this week, both a pull test and what I could glean from a ring test where I barely got a ring to look at after cracks ran, indicated that my expansion of the white base is too high. Pull bends toward white and what I barely got of a ring section with white on the inside, clear outside (Spruce Pine), overlapped after scoring.

Debating whether to add sand or take away some of the soda and/or potash from the next mix. Sand is currently at 55.4%, soda at 14.2%, and potash at 6.2%.
Borax and strontium are both a hefty 5.1% each but they are supposedly there to help the phosphate do its thing I think. Total batch weight of the next mix will be 35.2 lbs., before I adjust any.

Question: Given that I seem to be a bit high expansion and I couldn't saw a clean ring, any recommendations on how much I should try and move the calculated LEC down on the spreadsheet? 1 point to start? Less? More?
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