Using the IT

[mleuck]

When using the IT, will it be necessary to consider the thickness of the wood the IT is mounted on? It seems important, but I need some expert advice.

Thank you

Michael

[Gulf]

You can check that for yourself. Measure from the dead center of the pivot to the ID radius of your oven. Now, stand the IT straight up and measure that distance. If they are the same, then no adjustment is needed. Most of the time, the IT will need to be raised slightly from the oven floor to get those two numbers to match.

[DavidApp]

If you plan to have a soldier course you may need to raise the pivot point by the height of the soldier course.

David

[Gulf]

David,
I will have to disagree. That could also raise the ceiling of the dome by the height of the soldier course. The ceiling could then be too high. The pivot needs to stay very near the oven floor, only adjusting for the offset that is in most homemade ITs. I'm not a big fan of soldier courses. But, if one is included, the pivot may need to be lower than the cooking surface to get the radius of the oven and the height of the ceiling to match. An IT adjusted to fit a soldier course should yield a flatter dome. I hope that this diagram explains what I mean. In it, two ovens are drawn on the same plane. I did that to show what raising the pivot point by the height of the soldier course would do. The red radius is a true hemisphere oven. The blue is for a dome with a soldier course. Raising the pivot of the IT by the height of the soldier course would "marry" those two drawings together. That would yield a very tall dome compared to the width of the oven

[JRPizza]

Mleuck, I agree with Gulf you don't want to raise the IT to accommodate soldiers. Whatever you end up doing just make sure your oven and door height are within the recommended ratios so the oven will burn properly. I went with the recommendation of Gulf and others and did not use a soldier course. That, and keeping the pivot point as close to center of oven and at floor level should give the closest to a true hemisphere. My IT was centered but slightly higher than the floor, which I adjusted for. Have a look at post #36 in my build thread where I try to work through the IT placement. It might help and hopefully won't add to any confusion.

[DavidApp]

Hello Gulf

I used Half Batts for my soldier course. Can't remember exactly why I went that way. A lot of the ovens I was using as models for my build seemed to go that way.
My IT pivoted about 1 1/2" off the oven floor. I will check the diameter and height in the morning.
I did check the oven height when I calculated the inner arch height..

David

[deejayoh]

If your pivot is 1.5 inches off the floor, then as a perfect hemisphere, your dome will be that much higher than it it is wide. Do a search for my dome spreadsheet calculator, it will give you all the measurements you need.

If you decide you want a lower dome, then take a little length out of your IT with every course. Some builders use threaded rod in their IT for this reason.

[cobblerdave]

G'day
Make yourself a 1/2 cut out of your internal oven shape out of ply, taking into account the hinge height above the hearth. 1/2 cut out so it will still pass through the door when you get above door height. Use this every new brick level and you'll be able to reset the IT to reflect a low dome type oven shape with or without a soldier course
Regards Dave