Pots by Char Posted May 30, 2014 Report Share Posted May 30, 2014 I am substituting Gerstley Borate for frit 3124 in an 04 clay body recipe that calls for 30% frit 3124. I do not have any 3124 and cannot get any at this time. If I substitute Gerstley Borate for the frit will it work or will it cause problems? Thanks for your advice. Charlotte Link to comment Share on other sites More sharing options...
neilestrick Posted May 30, 2014 Report Share Posted May 30, 2014 It will not be the same. Post the recipe and we can try recalculate it with Gerstley. Link to comment Share on other sites More sharing options...
Pots by Char Posted May 30, 2014 Author Report Share Posted May 30, 2014 Thank you Neil. The recipe is as follows: Grolleg 25 #6 Tile 25 C&C ball clay 10 Frit 3124 30 Talc 5 flint 5 bentonite 2 I have all the other ingredients but no frits...I do have plenty of Gerstley though. Charlotte Link to comment Share on other sites More sharing options...
Guest JBaymore Posted May 30, 2014 Report Share Posted May 30, 2014 Aside from the TOTAL chemical differences in the two, the solubility of the Gerstly is probably going to be an issue, Neil. There is a reason you don't normally see GB in low fire (ir any) clay body recipes.... but "expensive" frits you do. But there is so much latitude in what people call "works"......... best, ............john Link to comment Share on other sites More sharing options...
Bob Coyle Posted May 30, 2014 Report Share Posted May 30, 2014 I have used 50:50 Custer and G.B. as a sub for 3124... but I am firing to cone 5-6. Even so I got some pin hole formation. I think G.B does some out gassing when it fires. Link to comment Share on other sites More sharing options...
neilestrick Posted May 30, 2014 Report Share Posted May 30, 2014 My bad. I was thinking we were talking about a glaze recipe, not a clay body recipe. Anyway, here's an option using Gerstley. Definitely mix up a test. Char Test.pdf Link to comment Share on other sites More sharing options...
Pots by Char Posted May 30, 2014 Author Report Share Posted May 30, 2014 Thank you Neil I will difinitely give that a try. Will let you know how it turns out. Link to comment Share on other sites More sharing options...
Bill T. Posted May 31, 2014 Report Share Posted May 31, 2014 Since you are in Austin, have you checked with Armadillo Clay? Their web site shows it. Link to comment Share on other sites More sharing options...
Biglou13 Posted May 31, 2014 Report Share Posted May 31, 2014 Wait didn't someone here say that the calculation/programs didn't work for clay bodies? Link to comment Share on other sites More sharing options...
Guest JBaymore Posted May 31, 2014 Report Share Posted May 31, 2014 The don't for anything other than general percentages of oxides. And Neil was thinking this was a bout GLAZES when he said that. best, ..............john Link to comment Share on other sites More sharing options...
Pots by Char Posted May 31, 2014 Author Report Share Posted May 31, 2014 well since I was in the mood to experiment I went ahead and made up a small batch (approximately 5 lbs) of this clay body using the original recipe and substituting Gerstly borate for the 3124 frit. It makes a lovely feeling clay..soft and smooth to the touch. Easy to work with for handbuilding (did a couple of pinch pots) and very easy to throw. Haven't tried slabs yets..will do a small slab tomorrow. It is a greyish shade of ivory wet and dries to a soft Ivory buff at bone dry..Now to see how it does in the kiln. I will probably fire either Monday or Tuesday..Still have some other things that need drying. Will let everyone know how it turns out. I may have to make a run to Armadillo and pick up some 3124 after all.. Link to comment Share on other sites More sharing options...
Pots by Char Posted June 3, 2014 Author Report Share Posted June 3, 2014 Well the kiln has finished firing and been unloaded. The experimental pieces with the GB 04 clay body came out great..no obvious flaws. It was fired to 06 for the bisque. Surface is smooth and flawless. Color is a pale ivory. The experiment pieces are quite light. It throws nice and thin. The pieces have a nice clear bell like ring to them when struck lightly. There was no cracking visible in any of the pieces. I will be glazing them in the next couple of days and glaze firing to 04. We will see then if there is any pinholing or bloat or other flaws at that time. So far I am quite pleased with it. I will keep you updated on how it goes. Here are a couple of pics of the GB 04 bisqued. Well maybe when I figure out how to add an image on here..sorry about that. Link to comment Share on other sites More sharing options...
Pots by Char Posted June 3, 2014 Author Report Share Posted June 3, 2014 Ok lets see if I have got this figured out on the images... Link to comment Share on other sites More sharing options...
Pots by Char Posted June 3, 2014 Author Report Share Posted June 3, 2014 John can you be a bit more specific on the solubility of the GB or lack thereof? What if I tweaked the recipe a bit and reduced the amount of GB to say 15% and increased the amount of tile 6 and C&C proportionately to cover the reduction? I am pretty happy with it as is but kind of wish it were a bit whiter. Aside from the TOTAL chemical differences in the two, the solubility of the Gerstly is probably going to be an issue, Neil. There is a reason you don't normally see GB in low fire (ir any) clay body recipes.... but "expensive" frits you do. But there is so much latitude in what people call "works"......... best, ............john Link to comment Share on other sites More sharing options...
neilestrick Posted June 3, 2014 Report Share Posted June 3, 2014 John can you be a bit more specific on the solubility of the GB or lack thereof? What if I tweaked the recipe a bit and reduced the amount of GB to say 15% and increased the amount of tile 6 and C&C proportionately to cover the reduction? I am pretty happy with it as is but kind of wish it were a bit whiter. Aside from the TOTAL chemical differences in the two, the solubility of the Gerstly is probably going to be an issue, Neil. There is a reason you don't normally see GB in low fire (ir any) clay body recipes.... but "expensive" frits you do. But there is so much latitude in what people call "works"......... best, ............john If you reduce the GB, you are reducing the fluxes, and if you increase the clay accordingly you'll end up with a body that isn't as 'tight'. If you decrease the GB, you'll need to make it up with another flux, like maybe talc or whiting. Link to comment Share on other sites More sharing options...
Pots by Char Posted June 3, 2014 Author Report Share Posted June 3, 2014 ok so lets say I reduce the GB by 10% and increase the talc by 10% , do you think that would make it a bit whiter? I am thinking that the GB may be what is giving it that creamy ivory look..but I may be all wet there too. Just making my first venture into trying to make a workable clay body. So I am kind of feeling my way like a blind mouse.. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.