Best way to finish the dome

[goanzio]

Hi to everyone on this great forum my name is christian and i live in perth western australia, i have been reading this forum for loooong time, and i really hope someone can help me, im building a 120 cm modular kit WFO on a custom build trailer, now the problem than im stuck is: i build the dome and put two layers insulation with the chicken wire on top, and here is where im finding a lot of questions to answer, first of all should i use vermiculite or not? Second i wsa thinking to finishthe dome with a strong sand finish render mixed of 4.1.1.1 sand,cement,lime,and blue metal dust.
Now can anyone tell me if its worth it or not and what kind of mix i should do for the vermiculite and how to work (i forgot to tell you im a hardwall plasterer by trade) do i need to mix sand,vermiculite,cement or i dont need the sand, and if so what should i do to make the oven as tough and sturdy as i can.

I know its a lot of questions but this problem is starting to effect my sleep and i want to do this project right in the first place without having major drama later on the road.
Thanks very much
Christian

[chubbybones]

Re: Best way to finish the dome

Hi goanzio,
Im no expert and im sure others will chime in but usually the ceramic blanket gets a layer of a vermiculite mix and then if you can finish it off with render.
If you have 2 layers of the blanketwhich is probably 50mm, it would not hurt to put another 75mm of a vermiculite mix on top of that.Thats what im about to do with my oven.
The vermimix should be just vermiculite and ordinary cement(portland).The ratio you use is personal preference.If you want something stronger you would use a 6:1 mix ,ie: 6 parts vermiculite: 1 part cement. If you are going for better insulation you could take the mix all the way up to 10:1.
Wait for some other responses though.
Good luck!

[goanzio]

Re: Best way to finish the dome

Thanks very much chubbybones and what do you think is better for a wfo on a trailer?and about the last cote of rendering what should i mix? Thanks very much
Christian

[chubbybones]

Re: Best way to finish the dome

Hey Christian,
Im really no expert.This is my first time building a pizza oven which is why i recommend you wait for some other guys to give their opinions before you proceed.Being on a trailer may require even more support/reinforcement if you're going to be driving it around.

I guess another option would be to use 4 layers of the ceramic blanket, put some chicken wire over that and then use your render mix.100mm of ceramic fibre blanket is more than enough insulation.
Your render mix seems pretty good to me and a lot cheaper than buying premixed render from bunnings.

Regards John.

[Liteceeper]

Re: Best way to finish the dome

Hi Goanzio
I'm no expert either, but here's what I did 50mm (2 x 25mm) ceramic blanket and then 50mm perlite render.
Exfoliators Litefill Premium Perlite and Brightonlite HE cement @ 5:1
Used 50mm corrugated conduit as a gauge for applying render.
Will finish with Drypak RenderCoat approx 5 - 8mm thick.
See my build