35 inch Pompeii Oven Build Saga

[Burns wood]

Re: 35 inch Pompeii Oven Build Saga

Great build thread, after looking through your build, I don't know if it helps build confidence or scares me more,

[david s]

Re: 35 inch Pompeii Oven Build Saga

In retrospect, since I let the oven dry naturally for >>several weeks, I would have been inclined to think it is better to do the dome insulation first before firing because it might have helped distribute and control the heat across the oven more evenly.

Brett

I agree, One of the problems of driving out the water with no insulation on is that there is a big difference in temperature and therefore expansion between the inner surface of the bricks and the outer surface which is a condition that is inviting cracking. The blanket will moderate this problem to a large extent. The trouble is it makes it difficult to inspect the outer dome surface to check for cracks once it has been covered in blanket or vermicrete. Plus the blanket will hold some of the moisture being pumped out of the dome. Remember, if you see visible steam then you are going too fast, let the fire die down.

[Greenman]

Re: 35 inch Pompeii Oven Build Saga

There are probably pros and cons for both methods. I have just done a week of curing fires without insulation and other than some fine cracks there was no issues. As the firings progressed the cracks settled to the extent that they closed and stayed that way for the last fire. It wasn't until the 3rd fire that moisture could be seen in places on the exterior of the dome and when that evaporated off after a couple more fires it was a good indication of progress.

I am presently waiting for the vermicrete to dry before applying the render coat. I expect that steady fires will be the way to go for the first few fires after it is all done.

Like David said, you don't really know what is happening under the insulation but it will probably assist in moderating the temperatures.

Cheers............. Steve