First pizza oven

[Mal47]

In early planning stages. I plan to cast a 2" hot face from home brew, cement/ lime and brick layers mud mix use alkaline fibreglass fibres as reinforcing along with burn out fibres. For insulation I was going to do 4" pearlite cement layer then a waterproof render on outside. For the stand I was going to build a wodden frame with a 4" slab of pearlite cement and fire brick for hotface. Plan to go with 50cm dome using a sand form lined with paper. Am I on the right track?

[david s]

Build the stand in masonry, Be very careful about applying vermicrete directly onto the inner casting. If you have moisture there it will create sudden steam which can be damaging. It’s better to have at least one layer of blanket between inner casting and vermicrete layers. It also acts as an expansion layer.
50cm internal Dian is very small 60cm would be better.

[Mal47]

I dont want a permannt fixture just something that will last 5 or so years and is possible to move if I have to.
point taken and I will put thermal blanket between hot face and insulation. Is the reinforcing along with burn out needles in the hot face a good idea?

[Mal47]

Sorry I got it wrong 50cm high meter wide. As far as insulation layer blanket do I need anything between pearlite crete and fire bricks?

[david s]

You won’t be moving a 1.0m Diam oven easily, you’d need a crane. A timber stand won’t be strong enough for it either. Calculate the weight, (density of homebrew is around 1.8kg/litre) add on significantly more for gallery, insulation, floor, external render etc. Supporting slab and fibre choice ok.

[UtahBeehiver]

Plus one on David's comments, with the exception, a pcrete floor is not strong enough for support layer only an insulation layer. You need a concrete support layer with rebar to support the oven then topped with a 5 to 1 pcrete insulation layer.

[MarkJerling]

I dont want a permannt fixture just something that will last 5 or so years and is possible to move if I have to.

If you must do it on a timber frame (which as others have said is not recommended) it can be done. If the total weight of the dome and floor and chimney does not exceed 1.25 metric tonnes then you'd need 200x50mm floor joists at 300mm centres, so in imperial measures, 2.755lbs on 8x2" joists at 12" centres. (Assuming soft timber like pine) You could use 4x4" legs and, provided you cross brace the legs, you will be able to carry the load easily. Bear in mind, of course, that you'll have quite a high point load on each of the four legs. You could, of course, have a horizonal brace at floor level too, which will further help to spread the load, depending on the floor surface you plan to place the oven on. I would consider that 4x4" legs would look too small (even though they can carry the weight) so if it was up to me I'd make the legs 4x6" or 6x6".

Such an oven will not be an easy thing to move, so you may consider building the whole thing on heavy duty castors. Each castor (assuming there's four) would need to carry a quarter of the weight. As can be imagined, it would make far more sense to build your oven on a block wall structure but I have had two clients who either wanted or needed timber structures for their ovens so it certainly can be done. Of course, you must make sure that you don't transfer high heat to the timber supporting structure so good insulation is very important.

[Mal47]

Looks like i may have to rethink either size or just make it permanant and hope i dont have to move..in a rental..