Initial build ideas - thoughts?

[di11on]

Re: Initial build ideas - thoughts?

The wider the door the easier the oven is to work, but you lose more heat. This can be compensated for by keeping a fire on the side. A well insulated and sealed door is important for any oven, but more so with one that has a wide door. The height of the door should be approx 63% of the height of the roof internally, give or take an inch or two either way.

Thanks David,

Cobblerdave mentioned here that the Forno ovens have a door opening of a little less than 50% of the internal diameter... I might just go with the design with the smaller opening in that case... as long as I can get a 12" Pizza in easily enough, it should be ok as far as I'm concerned.

[david s]

Re: Initial build ideas - thoughts?

The wider the door the easier the oven is to work, but you lose more heat. This can be compensated for by keeping a fire on the side. A well insulated and sealed door is important for any oven, but more so with one that has a wide door. The height of the door should be approx 63% of the height of the roof internally, give or take an inch or two either way.

[di11on]

Re: Initial build ideas - thoughts?

Hi folks,

I've attached the two alternative designs with dimensions in Inches this time.

The main difference is that design A has a wider and higher opening and a correspondingly higher dome - also, the bottom 4" is vertical and the elliptical curvature starts above this, so you get a slightly less curved dome. This is basically the Panyol 66 with a higher opening (the opening width is still the same as the Panyol 66 but is 65% of the oven diameter nonetheless.

Design B has a narrower and lower opening and the dome curvature starts from the very bottom.

Any thoughts feedback, particularly around the oven opening? I want to get the best balance between usability and heat retention. Are there any guidelines regarding the ratio of oven opening to dome diameter?

[di11on]

Re: Initial build ideas - thoughts?

Whoops.... Just realized your numbers are probably in metric. There's that peaty imperial system again....

The imperial system... the single worst thing the British ever did... and I'm Irish so that's saying something :-)

[di11on]

Re: Initial build ideas - thoughts?

Your oven opening is massive and could create a problem with oven and heat management. It should be half that width...at least.

I would not consider that done shape to be elliptical at all.

They are pretty much the dimensions of the Panyol 66... perhaps they can get away with a larger opening because of the higher quality materials used?

The dome is elliptical and the general form is that which I see in ovens here in France (which seem to be more focussed on bread baking). Although it's not what you consider elliptical, is there any reason it wouldn't work well?

Is the attached more like what you're thinking of?

[stonecutter]

Re: Initial build ideas - thoughts?

Whoops.... Just realized your numbers are probably in metric. There's that peaty imperial system again....

[stonecutter]

Re: Initial build ideas - thoughts?

Your oven opening is massive and could create a problem with oven and heat management. It should be half that width...at least.

I would not consider that done shape to be elliptical at all.

[di11on]

Re: Initial build ideas - thoughts?

Hi folks,

I've decided to go for a slightly larger sized dome. I've based the general size and shape on the Panyol but have increased the opening height a little.

The attached image shows the interior dome dimensions... how do they look?

The dome is elliptical - I know FB domes are parabolic whereas the "Roman" inspired designs here in France tend to be elliptical. I've done a little research here on the forum regarding the shape and I don't see any clear conclusions as to which is better, so in the end, I've gone with what is most pleasing to the eye.

Any thoughts on the general shape, dimensions?

[stonecutter]

Re: Initial build ideas - thoughts?

Even with mortaring, it wouldn't be that difficult to take it apart and move it.

[Tscarborough]

Re: Initial build ideas - thoughts?

If the sections have a lap, you do not need to mortar them, if not, you should, as well as build up on the outside of the joint to prevent burn-through.

[di11on]

Re: Initial build ideas - thoughts?

I found the assembly instructions for assembling that oven. They say to seal the joints with refractory cement. Do you think it would be useable without sealing them, or is there some easily breakable joint I could use?

Ideally, I'd like to be able to seal it weakly, add insulation and then an outer layer that I could chip off easily enough when the time comes... does this sound doable? I.e. it would be nice to disassemble the whole thing so it can be moved easily.

The instructions say you ideally want to add more thermal mass in the form of chamotte (crushed brick) - which I would do if installing it permanently. So the other option is to install it on a pallet which can be moved later, I just chip off the outer layer, take off insulation and then work back up from there.

I'm thinking though, once the sections are joined, there'll be no moving it off the pallet... not easily anyway?

To be honest, at that price, it's worth a shot and even if it comes to a bad end, I won't have lost that much.

Although, I was looking forward to the project side of things, starting from scratch.

We'll see!

[stonecutter]

Re: Initial build ideas - thoughts?

That looks like something like the brick I used for my oven. Uv doesn't damage masonry like that, so it's probably just the way it was cast. It's your call.

[di11on]

Re: Initial build ideas - thoughts?

Thanks sc, yes you did answer my query in relation to a segmented dome casting.

It looks like the oven has been exposed to direct sunlight for quite some time. It looks like there is some superficial flaking on the surface. Would this be an issue? I guess since it's designed to withstand over 1000 degrees F, it should be ok?

[stonecutter]

Re: Initial build ideas - thoughts?

I think that I answered that on another thread...maybe not. Anyway, you can parge the joints with mortar, but it will still crack. Parge the joints, wrap the dome with insulation, apply perlcrete or vermicrete, then stucco.

[di11on]

Re: Initial build ideas - thoughts?

Hmmm.... it could, couldn't it...

I might just take a trip back and see what it does and doesn't include

Edit: on a permanent install, would you seal those expansion joints with refractory cement, or would you leave them open... I think I've seen pictures where the whole things gets covered in a layer of something or other?!?