Locating the arch????

[david s]

Originally Posted by david s

The wider the arch the greater the heat loss, but the access to the oven is improved.

Generally the wider your arch is the greater will be the area that is presented to the outside, given that the height is fixed. It will be the frontal area of the arch that will lose heat through radiation and the fact that doors don't insulate as well as the insulated floor and dome. In my case of a small oven the doorway is a larger percentage of the oven area. This is one of the main disadvantages of smaller ovens.

[Neil2]

Buy some cast angle iron and make a rectangular opening.

Arched openings offer no practical advantage and several disadvantages (such as increased complexity in fabricating a door and the spreading of the arch over time).

[mrchipster]

Originally Posted by Neil2

Arched openings offer no practical advantage and several disadvantages (such as increased complexity in fabricating a door and the spreading of the arch over time).

Neil I am not sure why you say arched openings will "spread" if the opening is a true hemisphere it should be self supporting and free standing. No spread should occur. Unless you are considering the weight of the chimney to be a significant stress factor on the arch which it may be.

I still cannot in my mind come up with a stronger brick built design than an true hemisphere.

Chip

[Sharkey]

Originally Posted by mrchipster

I still cannot in my mind come up with a stronger brick built design than an true hemisphere.

Chip

I load tested my arch with a bit over 100kg (220 pounds). No problems.

Other than a hemispherical arch being inherently strong I think the arch being tied into the dome well prevents spreading too.

[GianniFocaccia]

Arched openings offer no practical advantage and several disadvantages (such as increased complexity in fabricating a door and the spreading of the arch over time

The advantage for me was the straightforward transition construction. I feel it was much easier than making and tying in the complicated frontal dome brick cuts required to fit a rectangular 'arch' or the traditional straight-sided shallow inner arch as called for in the FB plans.

Neil I am not sure why you say arched openings will "spread"

This is because true arches inherently exert side thrust. Practically speaking, I can't see an oven's inner arch spreading (ever) as long as it is properly tied into the mass of the dome. To me, the hemispherical arch has centuries of proven strength, clean symmetry, and was fun to build. Much more work than dropping in a piece of angle iron, but well worth it.

[dottavio]

I'd like to thank Cheesecake for starting this thread. You saved me a ton of grief and work. I had not thought about the placement of the arch inside the dome. I only measured the opening and height.

Since reading this post I have re-designed my opening. During the redesign I noticed that the distance of the arch from the center of the oven is dependent on the curve selected. The closer the arch is to the center the wider the horizontal opening which must be compensated by the arch side walls.

I am building a corner oven so my landing will be longer due to the diagonal of my stand so I needed a longer oven landing. In the attached you'll see the two versions of the 44" oven (round and oval). The oval will be more like the Neapolitan style even though the dimensions make it more of a hybrid. Using the oval I have a opening to height ration of .63. The 44" Premio2G has a ratio of .65 so I should be OK. I think I'll cut out some cardboard templates as a double check.

I laid out the floor last weekend and I will start the dome this weekend.

Hopefully all my readings in this forum will help me avoid more major mishaps.

[mrchipster]

Originally Posted by Sharkey

I load tested my arch with a bit over 100kg (220 pounds). No problems.

Other than a hemispherical arch being inherently strong I think the arch being tied into the dome well prevents spreading too.

Wow you have a great location for your oven. Do you have any wider angle views of where it is? And how are you planning to finish the exterior?
Chip

[Sharkey]

Originally Posted by mrchipster

Wow you have a great location for your oven. Do you have any wider angle views of where it is? And how are you planning to finish the exterior?
Chip

Thanks Chip. Here is my build thread. (Building Between a Rock and a Hard Place)

I keep changing my mind on how I'm going to finish it so I haven't done any work on it for a couple of months but it is cooking great pizza and bread.