u/lbfreund

I actually had a conversation the other day with Graham from Standard about this exact problem. I ordered 500 pounds of the last shipment. US gypsum is out of business, and you're not going to be able to get hydrocal or hydrostone anymore. As for Potter's plaster there's a company in Georgia that sells an identical product, and and he said they should be stocking it shortly. So all of Standard Clay Companies retail stores should be resupplied soon. As for hydrocal and hydrostone they're looking to source it from a German company.

During covid they were also out of plaster. I was stuck making molds out of the plaster from home depot. It worked just fine, though it's a little coarser and you need to add about 10% more.

To burp or not to burp? That is the question? Honestly it's a completely aesthetic choice, but yes, it makes a huge difference. Burping allows a little more oxygen in which changes the glaze. If you want more coppers, don't burp it. If you want more blues and greens, burp it. I'll illustrate, these two vases are the exact same glaze and the exact same firing, the only difference is one was burped and one wasn't.

Now as for putting the cans upside down in sand, it's a fairly common practice but your sand needs to be just a little bit wet in order to seal properly. More damp than wet really. And put the pieces on soft brick in the sand, not directly on the sand.

https://preview.redd.it/ssb8fookrwxh1.jpeg?width=4080&format=pjpg&auto=webp&s=433d0e1abb6a6147513c9991eb002f6a8ba830be

Make non-functional work. Pit or saggar fired potter that's burnished or sculpture.

The process was was originally developed in Germany. At the time people would bathe in the vapors because they thought it was rejuvenating.

Still lots of people salt and soda glazing ceramics around. The salt actually breaks into sodium and chlorine ions. The sodium reacts with the clay surface forming a sodium aluminosilicate glaze and the chlorine reacts with water vapor in the kiln forming hydrochloric acid vapor.

Hampstead Pre-owned treated me pretty well. I didn't finance though.

Time to test the clay bodies independent of the manufacturer. https://digitalfire.com/test/ssab

I don't believe they're trying to blame the studio. They're blaming the manufacturer, thus the comment about reformulation after the loss of EPK.

Yeah, can't tell some people anything.

Is that the Lear-Cordealia test?

You are absolutely fine. You're worried the ifb is so porous that's it's absorbed a ton of water, but in my experience that porosity let's it release water easily. Don't go too fast firing it, but really it's not a problem. For reference for many years I fired a train kiln with the same floor and it wasn't covered, never had a problem. Yesterday I fired a raku firing with wet soft brick and lot's of steam poured out, and nothing exploded. You're good. Now go find something else to worry about.

It's carved and then glazed to fill the holes.

Just fill it up and blow in it. It's really just that simple, I just use a cardboard box to catch the mess so I don't have to clean up

After a shower, the solution is clear. If I want to burnish, just burnish the pot like normal, not with terra sig. That way there's no fit or adherence issues. Unfortunately that takes quite a bit more time and effort.

Here's the other thing, I'm hoping it turns out to be a happy accident, because the more I look at it the more I like the effect. But again, it's not stable. So now the hard part is finding a way to do this on purpose where it's stable.

Exactly what I thought! And no I never glaze over burnished terra sig. I do a lot of burnished pit and sagger pieces. And I do separate glazed raku pieces. This was an experiment. But here's the thing, the glaze is stuck to the terra sig. It's not that the glaze didn't adhere to the burnish. It absolutely adhered to the burnish. It's the terra sig coming off the piece, the glaze just happens to be stuck to the terra sig. It took me a few minutes to figure that out.

Yeah, I'm going home to make naked now. I need a shower after raku.

Best I can think is the glaze adhered to the sig, and then shrink, which pulled the sig off the pot. And not by much, I'm really having to work to chip it off, but still off it comes. All that makes sense, but I use this sig a lot, over decades, and have rarely had a problem with it chipping off.

But why only with glaze over it? I've done literally hundreds of pieces with this clay body and this terra sig. And I've done dozens of pieces with this glaze on this clay body. No problems whatsoever. But I put this glaze over the sig and the sig comes off. Not the glaze. I thought at first the glaze didn't adhere to the sig, but no. Anyway, it's still something I'm going to play with it. Certainly I can just put the sig where I want it and the glaze where I want it, and not have to put the glaze over the sig. But that's way more of a pain in the ass. We'll see.

Agreed. Seriously contemplating a way to do this that would be stable. But alas, on this one it's just going to keep chipping off.

Effectively naked raku underneath.

Check out Paul Dresang

Check out Paul Dresang

If you pay attention, yes. If someone walks up and ask me a question and I stop, not as much.