63% rule for oven entrance

[fcastellino]

Hi

No matter how much time I spent in planning a designing my WFO, I was still able not to read about the 63% rule for the oven entrance. Now that I have completed the construction of my 42'' dome with a 11''-high opening and I am about to start the curing process, I read about this 63% rule and discover that I am not even at 50%. Too bad.

The question to you guys is - is this oven of mine going to work at all? What am I supposed to expect from it?

I must admit that I am rather disappointed. I paid a lot of attention to every single detail involved in the dome construction and then I probably ended up with an oven that may not perform as good as wished.

I look forward to comments from people who have worked with an oven with such a short entrance as mine.

Regards,
Francesco

[david s]

Re: 63% rule for oven entrance

I think you'll find it will work ok. Don't do any alterations until you've fired it at least 10 times. I've tried varying the ratio a fair bit and could not discern any difference in the way the oven fired.

[GianniFocaccia]

Re: 63% rule for oven entrance

I concur with David. Your door width looks wide enough to allow the oven to breathe okay.

I would be more concerned with the apparent lack of insulation below the oven floor. Coupled with a slow-breathing oven, it may be quite a task to bring up to temp.

[fcastellino]

Re: 63% rule for oven entrance

David, Gianni

Thanks a lot for your inputs. I am now slowly going up in temperature. Let us see how it will go.

Regarding the floor insulation, the floor right underneath the dome is made of leca-concrete. The thickness of that layer is 10 cm supported by an additional 10-cm-thick standard concrete. The total 20 cm thickness is not visible from the outside of the stand since the floor is only 10 cm thick when it gets over the stand perimeter.

Regards,
Francesco

[GianniFocaccia]

Re: 63% rule for oven entrance

Nice. With WFO's, insulation is your friend.

Any plans for a flue?

[fcastellino]

Re: 63% rule for oven entrance

Lots of plans - but no decision yet! I kinda like the idea of having the flue coming out from the top of the dome but I am still not sure how to make it.

Francesco

[GianniFocaccia]

Re: 63% rule for oven entrance

The top-mounted flue is called a squirrel tail and while it takes more work, looks really cool. Here's a look at how one of these is built:

MHA News - 2006 Meeting - Backyard Oven with Peter Moore