Iesa

Kiln problems Hey I have built a miniature kiln. I have done multiple styles. I have done a rocket style. I have done pit fire style and I have tried different variations of the same style. But I am unable to get the heat up high enough I have 100 fire bricks with the width of 2.5 inch and 9 x 4”. I also have some concrete bricks too, that I used at the top of the chimney. I am aware that because I am not sealing it off with mortar that I am losing some heat but I’m scared to seal it off with mortar until I’m confident on the design. I know I could use mud but I really want to be confident with the design before I have to go clean off the bricks again. if anyone has some advice on what style I should do with the amount of bricks I have that would be great. I have local clay that I’m using that has a really low sintering point. I think it’s even lower than terra-cotta due to all of the impurities in it. I know that because I managed to get one good fire and that was when I put the wood underneath the iron grill that I used as a kiln shelf and it was just a simple up draft kiln with a grate underneath the wood so I could get some air flow. The only problem with that design was that some of the fire was coming out from the wood feeding area and not shooting up the updraft. That’s why in the current version I'm using I made the dimension smaller so that I could have a longer updraft and so I could have a longer space to put the wood and it is working great very similar to a rocket stove. There is a strong roar and any water that’s inside the wood you can see and hear it sizzling at the opening (I know I shouldn’t use wet wood) and when you look in you can see all the flames burning blue and the draft is fantastic. I’m just confused why it’s not getting hot enough for the pottery. I even let the pots sit at the bottom and the coals surround them at the very end and then leave them in there all surrounded by orange Burning coals with a fan on them. But when they come out and I put them in water they semi disintegrate and crack with a strong grip. I enjoyed the fire clouds that the wood coals produce. I suppose part of the reason could be that I’m setting the pottery on the bottom of the kiln without a shelf holding it up, so potentially none of the coals are getting underneath the clay. But still with my thermocouple, I was only getting a reading of 1150 f with it stuck into the coal bed. I cannot get a kiln nor attend local kiln shops. Look forward for any comments and advice. Thanks