Sofusryge

I would not call that a small tabletop extruder, it looks pretty industrial. I haven't stumbled upon anything like it in the market, except for the little fiddly things that are sold on Amazon and Wish for extruding sugar paste and Fimo clay. I just bought a level-type extruder. I find it quite easy to use - it's mounted on a wooden support beam - no trouble. /Sofus

I regularly use a homemade rolling pin when i need to roll out large slaps. It's made out of a long piece of pvc pipe, filled with (casting)concrete. It's sturdy, heavy and dirt cheap to make - all things i find nice for a rolling pin. One needs to be carefull when rolling in from the edge of the slab, as the rolling pin has a tendency to pick up the clay as it's not porous. For smaller slabs, i make do with a solid beech wood rooling pin. It's Italian, and I think it's ment for rolling out pasta. But i like the heaviness of the pvc rolling pin better. /Sofus

Have a look at Strontium Crystal Magic and Jens Juicy Fruit. I use them for layering, primarily because they introduce a certain degree of flow in otherwise stable glazes. They are both good at cone 6. /Sofus

A wheel must be the epitome of portability :-) /Sofus

Fill a pvc tube with concrete and use it as a roller. It will be sturdy and heavy, and you can scale it to your needs. I think the real challenge will be to combine the slabs to make the pot. Slabs tend to be harder to handle as they get bigger, so very large slabs = very hard to handle. /Sofus

I use spooze made with honey regularly. Seems to work fine. Think the sugar is there for the stickiness - can't see what else it should do, as it is bound to burn out during the firing. I use spooze whenever i need something to stick properly, in situations where i can't "work" the pieces together. Both leather- and bonedry pieces. /Sofus

Why the chimney? It must make it difficult to determine when to pull the wares from the kiln, or is it detachable? /Sofus

Well, had some succes with the latest two pots. Went directly to the "reduction in the kiln" option, and it seems to do the trick. No dunts. But cooling in the kiln gives me a new challenge. Usually i just transfer the pots to the reduction bin, let the combustibles combust, and then put the lid on. Nice reduction, nice black color. In the kiln, the temperature is so high, that at first when i introduce combustibles, the carbon just burns out, leaving the ceramics as white as the day they came out of the bisque firing. I know it's a question about timing, the first pot got a nice black, as i fed the kiln combustibles at regular intervals. The second pot didn't get black at all, but som sticky soot that i can't seem to get off the glaze on the inside. Apparently, i missed the interval were the carbon has a proper effect on the raw ceramics, as i fed the kiln lots of combustibles, and there where both white and black paper ashes in the kiln afterwards. At what temperatur does the carbon penetrate the ceramics and produce the stable black color? Regards, Sofus

Thanks! I've sent a query to the Kilns & Furnaces company, hopefully they will be able to help. Regards, Sofus

I bought an old and battered top loader kiln some time ago. Today i bisqued a few things to try it out, and got a loud rattling buzzing noise (the noise is extremely annoying, kind of like an old digital alarm-clock) every time the kiln was in active mode (i ran it on 50%, apparently that means that it is heating in intervals - turning on and off every 5-6 seconds). Besides that, it worked a treat. I went to this forum, to look up the cause for the noise. Apparently, it is the relay that is getting worn out. I then opened up the back of the kiln, in search of the relay, but found a "magnetic contactor" instead. I then looked up the difference between a relay and a magnetic contactor. Seems its kind of the same thing, only the contactor is for more power. Now for the question - where to find a new magnetic contactor to replace the old noisy one? Is it possible to replace it with one of a different brand, and what to look for to get one that is compatible? The Kiln maker seems to be long gone, and a search for the contactor yielded nothing. Regards, Sofus

If you stuff the clay with loads of perlite, and then burn it out, you might get that "corky" look. Have a look at this work: http://antjhfoo.blogspot.dk/2010_02_01_archive.html Regards, Sofus

Thanks again for the remarks, it's much appreciated. The bottom of the pots are cut from the same slab as the sides, uneven thickness ought not be the problem. I'll try play around with the clay mix a little, and insulate the reduction container to see if it will fix the problem. I'll keep you posted if i succeed. Regards, Sofus

Here's the latest cracked pot. The horisontal lines coming in from the sides of the pot is merely glaze crackles, it's the vertical lines coming down from the top of the pot that is dunts in the ware. As mentioned earlier, i'm quite aware that the design is not optimal when it comes to thermal stress, but it's the design i want to go with here, so i'm quite eager to make it work. I'm not sure about the effect of pre-heating, the dunts are happening when cooling down.

Thanks for the remarks and suggestions. I will try to insulate my reduction-bin next time i fire one of the pots (still have 2 left to experiment with). I imagine that a container inside a bigger container, fillede with perlite in the hollow wall will do the trick. If not, i´ll try smoking directly in the kiln. The pieces have been bisqued to around 900c before firing in the raku kiln. Rakukuku: I would imagine that a hot pieces of kiln-shelf under the pot in the reduction-bin would make the temperature-difference between bottom and top of the pot greater, and maybe amplify the problems? I have propped the pot up on little bent pieces of steel (don't know what they are called), to get proper airflow under the pot in the kiln. Maybe i should do the same in the reduction phase. Chris Campell: i'm pretty sure the design itself is partly to be blamed, it really begs thermal stress problems. I'll post a photo. Shame about the paperclay, had high hopes that it would do miracles :-) Sand in the clay - duly noted. Perlite in the mix maybe worth a try too? Regards, Sofus

Hi This is such a nice place to gather information and inspiration. Lately I have experienced problems when finishing a series of rather large slab-built 2-sided elliptical bottomed pots in my raku kiln. They got what i guess is called cooling dunts going more or less straight down through the two faces of the pot. I have so far fired three and broken all. It doesn't seem to matter much, if i take the temperature slowly up (about 1 hour 20 minutes from cold), or fire as usually (about 45 minutes from cold). The breaking is clearly happening as the pots cool down in the reduction bin - sharp edges and smoke impregnated lines. I need the smoke for the design, so cooling down in the kiln is not an option. I'm using a raku clay from a local supplier, containing 20% chamotte. My raku-kiln is an oil drum lined with refractory fiber. The design of the pots is partly naked, partly glazed with Soldner clear. Any suggestions how to prevent this breaking? I've just mixed up a batch of paper-clay, as it should have good resistance to thermal shock. Is it likely that pots made from this will withstand the cooling better, or am i mistaken in believing that as an solution? Regards, Sofus Ryge Petersen