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Old 11-03-2003, 11:42 AM
Dave Bross Dave Bross is offline
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Join Date: Apr 2002
Location: Archer FL(near Gainesville)
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Virgin homemade clear batch melt

I thought I would try something simple for my first attempt at home batching so I went with the recipe Pete had published a while back:

100 Sand
28 Soda Ash
14 Lime Hydrate
12 Potassium Carbonate
200 grams potassium nitrate
100 grams antimony oxide.

I divided it by ten to get around 15 lbs. of batch and converted it to grams:

4536 Sand
1270 Soda
635 Lime
544 Pot. Carb.
20 Pot. Nit.
10 Antimony

7078 grams total or 15.60 pounds

I tested for moisture in the chemicals by cooking100 grams of each all afternoon and found I had moisture contents of:

1% Sand
5% Soda
2% Lime
1% Pot. Carb.
1% Pot. Nit.

The only thing I adjusted in the formula was the soda. I multiplied the total of soda (1270) by .05 to get 63.5 so I added an extra 63 grams of soda to make up for the water. I know this isn't exactly spot on because I'm making up the difference with wet soda and ignoring the 1 or 2% of water in other stuff, but close enough? I'm thinking I want slightly less expansion if anything because I'll be encasing some things and also have lower expansion colors I can use in case of COE troubles.

I tumbled it in a plastic pail rigged up in a cement mixer for 3 hours and began charging this morning. I'm charging at 2000F and it's going flat and ready for more in about 1 hour intervals. Sweet!

Gentleman, start your hammers!!! it's peer review/whack-a-mole time....

If you see any errors...please do speak up!

I'm thinking my next attempts will be some others Pete gave me involving borax or alumina from nepheline syenite....

Or .....

Am I worrying unnecessarily over glass stability/durability on a glass that will only be used for things like jewelry and C-balls?

Some of the old formulas I've seen for jewelry and knick-nacks have scary amounts of alkalai in them and absolutely no stabilisers, such as alumina or Borax, at all.
Art is not a's a way.
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