jan wallace dry glaze recipe - frit question

[carol socks-parker]

hello all,

has anyone experimented with jan's dryglaze recipe - wondering if anyone knows the equivalent for frit 4193 - we are looking for a USA frit that is equivalent for her frit 4193.  thanks, carol

[Norm Stuart]

Since the recipe uses just 8% Ferro Frit 4193, you can substitute Ferro Frit 3124 which will function similarly.

3124 melts at a nearly identical range, having 44% more refractory alumina which is offset by containing 50% more calcium oxide flux with 3% less Boron.

http://janwallacepottery.blogspot.com/2012/04/mucking-around-with-d...

As with substituting for the MOK-632 frit Alisa Claussen uses, you may want to make certain additions as both 4193 and MOK-632 contain Zinc Oxide and Barium Oxide, not typically found in American frits. For most glazes leaving these out doesn't make a difference, but in some glazes you need to add either the zinc or barium or both to replicate the look.

At the 8% level used in her recipe, this would be 0.22% zinc oxide and 0.16% barium oxide. Very small quantities. The extra calcium in the 3124 will more than provide the same additional semi-matte look zinc would supply, but zinc and barium both create color changes in many colorant oxides.

http://digitalfire.com/4sight/material/ferro_frit_4193_2980.html

http://digitalfire.com/4sight/material/ferro_frit_3124_350.html

Just the sake of information, this is the substitution I use for MOK-632.

It over-supplies Calcium Oxide which in some glazes can be removed by reducing other ingredients.

MOK-632 Substitute

75.0%    Ferro Frit 3134
30.0%    Borax
10.0%    Soda Ash
5.8%      Zinc Oxide
5.3%      Strontium Carbonate or Barium Carbonate
-12.8%  Calcium Oxide