Kaolinwasher Posted March 2, 2017 Report Share Posted March 2, 2017 i just got a 50 pound bag of custer , and then find out the chemical makeup is all over the place , which means i have to spend 30.00 every time i get a new bag it should be up to the company to be on the ball mine a large stockpile and them provide the analysis keep consistency . i found three different analysis so now i don't know if any thing i am making is just a waist of time i now will have to dump all tests and the feldspar not going back to it what a bummer . Link to comment Share on other sites More sharing options...
Fred Sweet Posted March 2, 2017 Report Share Posted March 2, 2017 Is there a lot number on the bag? If so, you may be able to contact the company to get a "typical" analysis of that lot to use. Link to comment Share on other sites More sharing options...
Dick White Posted March 2, 2017 Report Share Posted March 2, 2017 Sadly, this is the new reality for Custer. It isn't what it used to be, and they (Pacer Corp) don't care and won't admit it. Independent chemical analyses show the current material, since about late 2011, is lower in potassium than before (but still higher in potassium than sodium, so it still is classified as a potash spar), lower in alumina, and higher in silica. Thus, it is less of a flux, which is a problem since fluxing is what it is supposed to do. What is particularly maddening is that, contrary to Fred's totally appropriate suggestion just above, if you were to contact Custer they would swear that nothing has changed. Their website shows what they consider to be the typical analysis, and the numbers they continue to present have not changed in over 10 years. If you were to challenge them, they will blow you off as just another stupid potter. Their industrial customers are perfectly happy with the product. Link to comment Share on other sites More sharing options...
neilestrick Posted March 2, 2017 Report Share Posted March 2, 2017 We are at the mercy of the mines. There are very few, if any, glaze materials which potters use enough of to matter. The only reason we have any materials available is because industry uses them. Materials change, and we must adapt. Custer is by no means the first material to have this issue. It sucks, but get used to it. Link to comment Share on other sites More sharing options...
terrim8 Posted March 2, 2017 Report Share Posted March 2, 2017 Hey Kaolin- I probably asked you this before, but what are you using for a crusher and pulverizer? I would like to get two small economical units to do this in the backyard and I don't know where to look. Do I have to build them myself? I need small but not tiny machines- maybe something that could turn out 20 lbs of material. I've asked a local lab to crush and pulverize my stuff now but I would like my own equipment. Link to comment Share on other sites More sharing options...
Dick White Posted March 2, 2017 Report Share Posted March 2, 2017 We are at the mercy of the mines. I don't mind that we are at the mercy of the mines (actually, I do mind, wish it were not so, but it is and we can't change it). What I mind is that Pacer Corp is stonewalling us on this. A counter-example is the behavior of Imrys, producers of the now-unavailable G200 spar. When the original G200 mine ran out, they blended soda spar with the higher potassium spar they were getting from a new mine so that it would be equivalent to the old material. Then the economy turned and they decided for business reasons to stop blending. But then they announced to everybody what was going on and how to blend your own, and also published a statement of the analysis of the new material. Totally upfront and transparent. Now we know what we have. Pacer didn't, won't, and sneers back at you if you challenge them. Link to comment Share on other sites More sharing options...
Min Posted March 2, 2017 Report Share Posted March 2, 2017 @kaolinwasher, Not sure if I read your post right, did you get an analysis done? If you did could you share how the results were compared to this? Silica (SiO2)…………………………………………… 68.5% Alumina (Al2O3)……………………………………………………. 17.0% (16.5% min) Iron (Fe2O3)………………………………………. 0.10% (0.15% max.) Soda (Na2O)……………………………………………………….. 3.0% Potash (K2O)……………………………………………………….. 10.0% (9.5% min.) Lime (CaO)……………………………………….. 0.3% Magnesium (MgO)……………………………….. trace Link to comment Share on other sites More sharing options...
neilestrick Posted March 2, 2017 Report Share Posted March 2, 2017 We are at the mercy of the mines. I don't mind that we are at the mercy of the mines (actually, I do mind, wish it were not so, but it is and we can't change it). What I mind is that Pacer Corp is stonewalling us on this. A counter-example is the behavior of Imrys, producers of the now-unavailable G200 spar. When the original G200 mine ran out, they blended soda spar with the higher potassium spar they were getting from a new mine so that it would be equivalent to the old material. Then the economy turned and they decided for business reasons to stop blending. But then they announced to everybody what was going on and how to blend your own, and also published a statement of the analysis of the new material. Totally upfront and transparent. Now we know what we have. Pacer didn't, won't, and sneers back at you if you challenge them. I get it, but it's obviously not going to affect their profits enough to do the work. Whatever Custer is being used for in industry is apparently unaffected by the change. The inconsistency of Gerstley was the same. It was used by the roofing tile industry, which didn't care if it was not the same from year to year. Link to comment Share on other sites More sharing options...
Dick White Posted March 2, 2017 Report Share Posted March 2, 2017 @min The analysis you listed appears to be as stated by Pacer, and has been their standard party line unchanged for at least 15 years. I did not have any analysis done myself, but Ron Roy did. Here is his work, as published in Ceramics Monthly a few years ago. http://ronroy.net/analyses/custer-spar-9-analysis.html Link to comment Share on other sites More sharing options...
Min Posted March 2, 2017 Report Share Posted March 2, 2017 @Dick, Thanks, yes I had seen that. I wanted to see the difference between what Pacer is listing and what a current up to date analysis is showing. (maybe we should pool our nickels and dimes together and get another one or two samples done) Link to comment Share on other sites More sharing options...
Dick White Posted March 2, 2017 Report Share Posted March 2, 2017 yes, that would be interesting to see if there is further drift since Ron Roy did his work. Link to comment Share on other sites More sharing options...
perkolator Posted March 2, 2017 Report Share Posted March 2, 2017 Has happened before and will happen again with certain mined minerals. Industry changes, the vein of mineral in the mine changes, etc, we get very little opinion or control if any. If it weren't for industry mining these minerals for other purposes, we wouldn't even have access to them for ceramics - selling off part of their product inventory to some hobbyist ceramicists is not even a fraction of their income, so why would they change things according to our needs vs that of industry? Link to comment Share on other sites More sharing options...
Min Posted March 3, 2017 Report Share Posted March 3, 2017 Not asking for change, just for Pacer to update their tech specs. With glaze calculations it runs the risk of turning into garbage in garbage out otherwise. Link to comment Share on other sites More sharing options...
MatthewV Posted March 3, 2017 Report Share Posted March 3, 2017 It has been "good enough" for me too. I haven't had issues with glazes which use potash feldspar. Link to comment Share on other sites More sharing options...
Dick White Posted March 3, 2017 Report Share Posted March 3, 2017 It works well enough in cone 6 glazes that only have up to 25% Custer in the recipe. If the recipe has more than 40-50%, it doesn't melt out. Link to comment Share on other sites More sharing options...
glazenerd Posted March 4, 2017 Report Share Posted March 4, 2017 If my memory serves correctly: Ron discussed Custer back at NCECA in March- I do recall him saying 7-8% range if I am not mistaken. Nep SY and Custer are used in bulk to control chemical spills: it is the absorption value that sells it to industry: not potash levels. Yes indeed, our beloved feldspar are thrown onto floors and swept up. Nerd Link to comment Share on other sites More sharing options...
Kaolinwasher Posted March 4, 2017 Author Report Share Posted March 4, 2017 I talked with a guy from Minnesota clay co . and he said he has seen no difference in what they make with it and they use it elusively for everything clay bodies and glazes , He also said that they had equipment problems and could not make the 200 mesh for some time but now have that fixed - my worry is if what they now sell is more like a granite than a feldspar i will have problems I plan on getting it tested but i want to send in some other tests with it as it would cost 52.00 just for one sample Terrim8 i use a small 1"x 2" jaw crusher from 911 metelergical and i crush my granite or waterer down to 30 mesh them ball mill it the small crusher is about 500.00 they also make a 3x4 that has a groves crush plate and its really nice but about 1800.00 my small crusher just broke as well its the bolt that sets the gap for crushing it stripped out so i am going to make my own stop for it some welding involved otherwise you can get a K& M crusher hammer mill for about 1500.00 but you have to be very car full aout the dust the hammer mill can come with the dustless system the small 911 crusher is a very good machine but its just that bolt that can be a problem I think i will start using Mahivar feldspar Link to comment Share on other sites More sharing options...
neilestrick Posted March 5, 2017 Report Share Posted March 5, 2017 I talked with a guy from Minnesota clay co . and he said he has seen no difference in what they make with it and they use it elusively for everything clay bodies and glazes , He also said that they had equipment problems and could not make the 200 mesh for some time but now have that fixed - my worry is if what they now sell is more like a granite than a feldspar i will have problems I plan on getting it tested but i want to send in some other tests with it as it would cost 52.00 just for one sample Terrim8 i use a small 1"x 2" jaw crusher from 911 metelergical and i crush my granite or waterer down to 30 mesh them ball mill it the small crusher is about 500.00 they also make a 3x4 that has a groves crush plate and its really nice but about 1800.00 my small crusher just broke as well its the bolt that sets the gap for crushing it stripped out so i am going to make my own stop for it some welding involved otherwise you can get a K& M crusher hammer mill for about 1500.00 but you have to be very car full aout the dust the hammer mill can come with the dustless system the small 911 crusher is a very good machine but its just that bolt that can be a problem I think i will start using Mahivar feldspar Not trying to be a ########, but punctuation would really make this easier to read. Link to comment Share on other sites More sharing options...
Dick White Posted March 5, 2017 Report Share Posted March 5, 2017 Interesting that your source says they repaired the 200 mesh grinder. Their original statements at the time the machine broke indicated they had no plans to repair/replace that machine, henceforth 325 mesh was all they would make, get used to it. Link to comment Share on other sites More sharing options...
glazenerd Posted March 5, 2017 Report Share Posted March 5, 2017 I started using Mahavir a year ago or so: so far it has proven to be very consistent. 11.50% potassium and 3% sodium. What I do not like about it is the very low alumina levels: which can be compensated elsewhere. I am a big fan of the technical grade Mica I use (air floated / magnet milled) that is pure potassium (13%) and alumina (39%), with no iron, titanium, or magnesium. I use mica primarily in clay bodies. At the end of last summer I did blend some mica and mahavir 50/50 for use in glazes. It does melt very well, but I have not used enough yet to make any final conclusions. Calcium borate will melt just about anything, rather fond of it as well: been experimenting with it for cone 1-3 glazes.Too bad the Death Valley mine closed: they had some large deposits of Ulexite: even better. Nerd Link to comment Share on other sites More sharing options...
Kaolinwasher Posted March 8, 2017 Author Report Share Posted March 8, 2017 I am getting ready to send in a sample of custer > And we will see .Should be about a month from now . I use ALS labs in Nevada.. Link to comment Share on other sites More sharing options...
Kaolinwasher Posted March 26, 2017 Author Report Share Posted March 26, 2017 myanalysis will be delayed a bit > i was short 1.85 so had to send that in but there working on it and we will see whats in dust now hopefully in april Link to comment Share on other sites More sharing options...
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