Search the Community
Showing results for tags 'bentonite'.
Found 4 results
Hi all, I'm based up in Finland and we have a lot of very clean local clay deposits. It's grey and fires to a dark red brown at the top end of it's range which I would guess is around 1100C looking at the glow. (the test we did was in a self built wood downdraft kiln without any cones or thermocouple. It started to boil and melt) There was a brick works on the site where I got the clay up until the '50's, so I know the clay is usable in some form or another. There is a LOT of clay around here, I guess as a result of glaciation? I dug a heap of clay about 15 years ago and it's been wrapped up outside getting deep frozen every year (-40C) I dried and washed a bucketful a few years ago which has been stored indoors since then. After hand wedging the clay it has a good smooth consistency but it feels quite strange. It almost like a gel?? It cracks and breaks as soon as you try to stretch it, but when you make a large ball of it, it starts to sag. If you manipulate it very slowly, say by squeezing, it deforms readily without cracking? It is not sticky at all, although in the bucket it looks like it should be as there is a fair bit of surface water on the clay. I don't have much experience with raw clay but I guess this needs an addition of a plastifier like Bentonite or Ball Clay or something? So a couple of questions... Should the clay be dried and powdered first? Or can I just work out the water content and wedge the appropriate amount of plastifier into it? ....and what percentage of plastifier would be a good place to start? Thanks in advance Rod
Hello! I got all the ingredients today to mix my first batch of glaze - Kitten’s Clear - from John Britt’s book on mid-fire glazes. Trouble is, the recipe calls for an added 2% of bentonite and the girl who helped me gather all the ingredients either missed/skipped or forgot it. How essential is the bentonite? Can I proceed without it? I plan to add some whiting and stain. If it’s essential, can someone link a good place to buy some online? I actually have a 100% bentonite clay powder I use for a face mask - would that work as a replacement? thanks!
Need some input, point/s of reference. 1. Do you add bentonite, EPK, or gums to your glazes? 2. In what amount do you add to the final (dry) batch weight? 3. Do you add more for high magnesium or sodium glazes? 4. Have you had problems with bentonite clumping? 5. Do you rely on additives to achieve viscosity? Nerd
I have been making porcelain, and i was using regular bentonite, and noticed dark specks in the clay after firing , wo i decided to mix three grams up in to one cup of water and stir it for three days off and on but what i found out was after i poorer it into my clay test all the heavy junk settled and never made it into my clay body- so now i know this stuff is not so refined not that it can't do the job, I am just going to have to wash it real thin and let the junk settle you can see the black grit in the bottom of the cup