Thread: ring tests
View Single Post
Old 10-25-2019, 05:08 PM
Josh Bernbaum Josh Bernbaum is offline
Registered User
Join Date: Feb 2009
Location: Brattleboro, VT
Posts: 657
Josh Bernbaum is on a distinguished road
The simple pull test showed that the phosphate white was higher in expansion than the SP clear. It bent toward the white a decent amount I'd say.

Here's a formula posted here by Dave in 2016:

Sand 97.5
Soda 36
Lime Hyd. 5.5
Strontium 9
Zinc 3
Borax 9
Alumina Hyd. 4.5
Lithium 1
K Nitrate 1
STPP 6.5

Mine is very similar to that, just put in some K carbonate instead of some of the sodium carb. I calculated his percentage of sand at 56%, by dividing 97.5 by the total weight of 173. But maybe I'm going about that percentage calculation totally wrong, because I see Dave listed the SiO2 content of the above formula at 65.32%. I'm guessing that's more in the range of what you'd like to see for sand content. If Dave is correct on that, then that will be very similar to where my sand content is at as well.
Reply With Quote