Why smooth dome ? Why not multi sided stepped dome ?

[uk_exile]

Creating a smooth circular dome seems to create a lot of cutting work, angles, wedges etc. I understand circular dome works better than a barrel vault oven but would a simple multiple sided stepped dome work ok ???
i.e. use say 12 full bricks on first row then reduce to 11 next row, laying them flat, no wedges, perhaps 10 next row again flat then, say 8, 6 etc until the stepped dome is closed.
I know interior will be a bit 'chunky' so airflow wouldn't be as smooth but would that really matter ? Higher rows could be half bricks rather than full bricks however there would still be steps between each layer. Of course structurally it wouldn't be as strong as a proper angled dome but a bit mortar would hold it together I think.
Just a labour saving thought that's most likely been covered many times but there's so much on here I couldn't find it using search.

[brickie in oz]

Re: Why smooth dome ? Why not multi sided stepped dome ?

Any shape will work, what ever floats yer boat.
Its all about thermal mass and insulation.

[david s]

Re: Why smooth dome ? Why not multi sided stepped dome ?

Having a flat surface pointing toward the centre of the hemisphere, you would think that you'd get better heat reflection and radiation.But maybe it doesn't matter that much.

[Lburou]

Re: Why smooth dome ? Why not multi sided stepped dome ?

In the back of my mind, I'm thinking there is something lacking in the support for each chain that way....I don't think it would be as strong.

May be strong enough, but with the dome constructed per the plans, you know it will be sturdy enough. I recommend a safe way out and build according to the plans. It doesn't have to be purdy

Good luck!

[dmun]

Re: Why smooth dome ? Why not multi sided stepped dome ?

Of course structurally it wouldn't be as strong as a proper angled dome

This would be less true on the first chains that only overhang by an inch or less, but when you get to the top of your dome, you are going to have more brick hanging out than the part that supports it, and you run a serious risk of failure.

a bit mortar would hold it together I think.

I wouldn't count on any mortar having much tensile strength. Heating and cooling ovens are in constant motion, and at the first bit of cracking you're going to loose any "glue" effect.

Creating a smooth circular dome seems to create a lot of cutting work, angles, wedges etc.

Perfect fit domes are an exercise in craftsmanship only. The original pompeii plans called for bricks halved with a brick set, and an opening supported by angle iron. Major brick cutting will yield a dome that looks better, but not one that cooks better.

[brickie in oz]

Re: Why smooth dome ? Why not multi sided stepped dome ?

you are going to have more brick hanging out than the part that supports it

Not if you only corbel each course 40mm you wont..

You would have to support the oven when building it, but once built it should be self supporting.

[uk_exile]

Re: Why smooth dome ? Why not multi sided stepped dome ?

I might have a play in CAD to see what it would look like. Perhaps it gets would need to be a bit more cone like than squashed down cone / dome

[lwood]

Re: Why smooth dome ? Why not multi sided stepped dome ?

Don't think that configuration will result in that much less cutting, especially towards the top of the dome.

[uk_exile]

Re: Why smooth dome ? Why not multi sided stepped dome ?

Don't think that configuration will result in that much less cutting, especially towards the top of the dome.

But think about the ease of just stacking the bricks flat. Some support would be needed until the mortar sets on upper layers.

Perhaps structural strength and not any smoothness of airflow or smooth surface for reflected heat is the primary reason for the more labour intensive dome design used for centuries.

[uk_exile]

Re: Why smooth dome ? Why not multi sided stepped dome ?

Didn't work as well as I hoped. Too many gaps

[brickie in oz]

Re: Why smooth dome ? Why not multi sided stepped dome ?

Didn't work as well as I hoped. Too many gaps

Use half bricks on edge and turn them 90 degrees, there will always be big gaps using full bricks stretcher style..

[Lburou]

Re: Why smooth dome ? Why not multi sided stepped dome ?

Didn't work as well as I hoped. Too many gaps

The other down side as depicted would be a lack of mass with 2.5 inch thickness. If I'm understanding you correctly, that would be a show stopper because it would not hold the heat.

Glad you have moved on.

[lwood]

Re: Why smooth dome ? Why not multi sided stepped dome ?

as you get closer to the top of the dome the gaps get bigger...or you have to make cuts. Did you look at laying the bricks on the face rather than the edge of the brick? More surface area to stick to. That looks like a very difficult build. Plus you only have 2" of fire brick, you need 4".

[Tman1]

Re: Why smooth dome ? Why not multi sided stepped dome ?

You don't need to make it round... (check the link in my signature) but it sure looks better that way. I can confirm that it makes great pizza, and the next time I fire it I'm hoping for bread too.

[uk_exile]

Re: Why smooth dome ? Why not multi sided stepped dome ?

That's a wicked oven and so fast to build. Liking it ! ......however it won't meet with my CFO approval as she likes things to be 'tidy'. Bugger