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I do use a ball mill but only after I have used the frit crusher to take it down to a coarse or medium size. The ball mill works well for reducing the frit to a fine frit.

Thanks Tony. I hope it won't have an effect on the glass but that will probably vary with the composition of the glass. As in most things, only trying it out will tell. I certainly don't want to change the makeup of the glass (not if I want to maintain compatibility).

I ran onto the information about the acid wash in a dissertation from the Rochester Institute of Technology. The idea is to wash the frit with the dilute acid and then do a few rinses before neutralizing it with a base wash (baking soda solution). I have worked with metal salt solutions before and I...

I know that hydrochloric acid is used as a pickling solution for steel to dissolve scale so my thoughts are that it might work on the small amounts of iron that might be present in the crushed frit.

Thanks Brad. I know that I will be getting a little iron in the frit when I crush it but I read where a 10% solution of sulfuric acid will clean it out. I have easier access to hydrochloric acid and I was wondering if it would work as well as the sulfuric?

I recently got a frit crusher and I will be using it initially to crush a large supply of system 96 scrap to use for pate de verre work. When I run out of clear scrap, I was considering crushing system 96 cullet. Will the crushed system 96 cullet be compatible with the crushed system 96 sheet glass?...

Morganica, I have decided to try out fiber as an additive as you suggested but I have some questions. I assume that you are referring to chopped ceramic fiber not chopped glass fiber (as used in cement), am I correct? What fiber length are you using? My molds vary quite a bit in thickness so I am al...

In the past, I have been mixing silica sand (#4030) with standard moulding plaster. It gives me a mold that lasts for five or six firings and for most jobs that is fine. For a current job, I would like to increase the durability of the mold. The Ultracal when mixed the same way, maintains a good sur...

What are the best sand or grog particle sizes to add to Ultracal plaster to get the most durable mold for firing to 1400F? Which is preferable, sand or grog?

Does anyone out there have any experience making frit with the "Crazy Crusher"? I know that it is designed for crushing rock samples but I assume that it should work for glass as well.

Thanks Bert, It appears that one thing that is different this time is the mold mass. I thought originally that there would be more of an issue with the large molds heating up too slowly but in fact the large molds seem to heat up faster than the small ones. It is probably due to heat retention in th...

What I do is run up to 1250F slowly and then go on high the rest of way to the temp needed to do the drop. Because of the speed of the temp increase, the actual glass temp lags a little behind the air temp that is read by the pyrometer. That being said, I did drop my top temp from 1350F to 1335F and...

Thanks Kevin, I realize that all of those are possibilities but I am still wondering about the possibility that the Ultracal is off gassing something different than the standard low density plaster that I usually use. After I finish this project I will conduct some experiments on smaller molds to se...

I have been using this particular glass for twenty some years now and have not had the problem that I am having now. I am not taking it to fusing temperatures but rather bending temps (1350 F) and my cleaning technique isn't any different than it has been for hundreds of other panels. It may be devi...

The glass is Kokomo 145. It's an amber and white opal.

I am bending quite a few large lamp panels and I am having a problem with getting inconsistent dull areas on the surface of the glass after I fire them. In order to get the molds to be hard enough to withstand a large number of firings, I have made them by first laying down a layer of Ultracal 30 an...

Quite a few years ago I was asked to make some 48" glass bowls using 1/2" plate. I made the assumption that I could fabricate a mold that would work out of some refractory material or clay. I spent a lot of time and some money trying to make molds. The molds were failing because of the wei...

Are all mica powders the same in regard to their temperature limits? I picked up some mica powders from a pigment company and they seem to be burning out at lower temps than I want. Any information would be appreciated.

I know that you probably don't have enough room to build a stand aside studio but that would be my first suggestion. I know of too many people who have lost studios to fire because of kiln accidents. If a stand apart studio is out of question, then you should make sure that your fire wall between yo...

Thanks for the warning Bert. I am not too fond of gas either but I am just exploring the possibilities. I have some other possible solutions to create a limited reduction atmosphere in an electric kiln that I will explore first. Actually I am kind of obsessive compulsive when it comes to protecting ...