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Last year I decided to resume my passion for modeling clay and in particular stoneware and porcelain clay. I decided to specialize in single firing (I had a book taken in Scotland several years earlier). At the moment I'm cooking at 1240°C, non-stop. The cooking lasts 3 hours between 0 and 200°C and then travels at a speed of about 100°C per hour (if I remember correctly: the oven is not mine). I'm doing glazes experiment using wood ash. This idea came from the fact that we use the fireplace and in particular the pellet stove for the winter. Wood ash from the pellet stove is probably not ideal: because some of the finer particles are lost and the sieve work is longer and give a coarser material. But I have a lot of ash from this stove and it's a shame not to use it, if possible. I had some book from Scotland about ash glazes and cone 6 glazes and I'm starting from them. To make my life easier, I use wood ash washed several times but I do not dry it: I let it settle and remove the surface water leaving only about 1 cm of water. At the beginning I used a volumetric system in the first 2 recipes (photos). Recipe 1: - 1 jar of dense slip of 1250°C spotted stoneware clay - 1 jar of thick potassium feldspar slip - 2 jars of dense wood ash slip Recipe 2: - 1 jar of dense slip of porcelain clay - 1 jar of thick potassium feldspar slip - 2 jars of dense wood ash slip. Than I made 2 little experiment with a little of cobalt and copper oxide. I calculated that those slips contain about 50% water and 50% clay or feldspar. Instead, I estimate a quantity of about 300 grams of dry ash in a liter of ash slip. The calculation is very approximate but the second experiment I am conducting is based on this hypothesis. Now I bought the different dry raw materials and a precise scale, so I weighed the ingredients precisely. However, I still use a very dense ash slip instead of dried ash: drying the ash would be too much work at the moment. I'm preparing the basic recipes for the next experiments. For now I have prepared the first two recipes based on the first experiments: First recipe: - 1 kg potassium feldspar - 1 kg ball clay - 170 gr bentonite - 500 ml pheatine - 2 liters of water - 4 kg dense ash slip Second recipe: - 1 kg potassium feldspar - 1 kg china clay - 170 gr bentonite - 500 ml pheatine - 2 liters of water - 4 kg dense ash slip I'm looking for other simple basic recipes to try. Something that can introduce someting new for the experiments with oxides. I have tried to modify some recipes of "Glazes cone 6 1240°C" book of Michael Bailey: exchanging whiting with wood ash, dolomite with wood ash and talc, exchanging soda feldspar and litium carbonate with spodumene, adding 5% bentonite for single firing. I am trying to modify a cone 8 recipe of the book "colour in glazes" of Linda Bloomfield exchanging soda feldspar with spodumene and calcium borate frit with colemanite, exchanging whiting with wood ash and using a litle less quartz hoping to fire successfully at 1240°C instead of cone 8. Looking to my books these are some ideas to try: Recipe 3 (recipe T13 modified from Michael Bailey book): 830gr soda feldspar, 130 china clay, 140 bentonite, 430 quartz, 120 Zinc oxide, 1,5 kg wood ash dense slip. And pheatine. Recipe 4 (recipe T14 modified from Michael Bailey book): 1kg spodumene, 500gr china clay, 160 gr bentonite, 500gr dense wood ash slip, 100gr talc, 100gr zinc oxide, 240gr quartz. Recipe 5 (recipe OR1 modified from Michael Bailey book): 1kg spodumene, 130gr china clay, 150gr bentonite, 322gr bone ash, 16gr litio carbonate, 362gr talc, 244gr quartz Recipe 6 (recipe for chromium green modified from Linda Bloomfield book): 1000gr spodumene, 320gr colemanite, 1000gr dense wood ash slip, 107gr china clay, 300gr quartz, 107gr bentonite. I hope to use this recipe with chromium to obtain a green glaze.

I'm a beginner potter and I've tried wood firing pottery outdoors because an electric kiln is not very accessible for me. My small kiln is about a bit bigger than 2'x2'x2' and made from regular red bricks with a regular grill grate halfway to place pottery. As you can probably tell, it has terrible insulation and I can never get it to a high enough temp to fire glazed pottery. I can bisque fire and it works but It never gets hot enough to melt glaze, even the low fire glazes I use. I really don't want to ditch this project because I've already put so much time and material into it but I don't have the time/material to build a much bigger kiln or spend days firing. I also don't have a huge budget. What fairly inexpensive materials I can use to insulate my small kiln so that it can comfortably reach cone 06 and complete a glaze firing? I've looked into getting ceramic fiber board to line the inside of the kiln with, fire bricks are very expensive and probably out of my price range. Any advise from someone with more experience in this field would be very appreciated, Thank you!