DIY Kamado, Has anyone done any experiments with vermiculite refractory concrete?

[db964]

 

 

 

 

 

 

 

 

 

I have a funny feeling when I fire this up itll crack apart, plus I think my vents are too small....ive put vermiculite, smashed up storage heater bricks and refractory cement in a 3:2:1 mix with an outer coating of fire putty to theoretically give a good surface for tandoori naan cooking perhaps, although this thin coating i cant find anything online to say if fire putty is stable enough to work this way.... plus also does the fire box of a Kamodo have to be insulated if the outer coating is insulated?

 

Cheers

 

Dave

 

 

 

 

 

 

 

 

 

 

 

[Jack.]

 Dave.  That's a great looking DIY project kamado.  Good luck with the results.  Although I'm not entirely sure what you mean by an "insulated" firebox, I've not seen a firebox with any applied insulation-only the material from which it was made, exposed inside and out. 

[db964]

Hi Jack,

as in why not use a stainless bowl as a firebox... the firebox that seems to come with them is ceramic insulated...I was just wondering why

cheers Dave

[TKOBBQ]

Maybe more thermal mass equals better stability of temperatures?  Nice looking DIY project. 

[ndg_2000]

Hi

 

I made this Keg Kamado but I used a perlite because i was worried about the vermiculite and its possible expansion under heat.

 

If you have any questions please ask i may not be able to answer all of them but have a read of my thread below it will give you a good idea of what i have done to keep my little kamado going 
 

 

[ndg_2000]

hi

 

I re-read your post again is the white item in the back of the photo going to be your fire box ??

 

I don't think the fire box HAS to be insulated but with the store bought kamados it does add thermal mass which helps to regulate the temps 

 

my little kamado didn't have a separate fire box simply because I didn't have enough room and it worked well.

 

Air inlet and outlet wise the only realistic way of knowing if the size is right is by firing it up and trying it out. Even the store bought ones come with a bit of learning of the vent settings and to be honest most of the time the vents are almost shut if you want smoking temps. 

 

I would spend a long time on your first fire up slowly raising the temp's on it even running an old filament light bulb inside the kamado for a few days just to help dry out the inside lining then start with a small hand full of charcoal and slowly increasing the amount burned till you get up to where you want to go. If you go too fast too soon the coating will blow because of residual water in your mix (the water boils then finds the weak spots to pop off the coating)

 

hope this helps good luck 

 

Nigel 

 

 

[db964]

Hi Nigel,

 

No the stainless bowl next to it has become the firebox. I also thought, if the kamodo firebox is ceramic it must be made for a reason that way... so I used that stainless bowl and surrounded that in vermiculite concrete as well. To reflect and hold in the heat.... hopefully...

 

Thanks for the reassuring comment on vent sizes, I have been worried as to change it, it would be destructive! 

 

The next few days/weekend il  leave the heater blowing up it the fear of popping the coating will keep me cautious. 

 

Next is the heat deflector... I read on this forum somewhere that a stainless disc filled with silica sand would be best... so will be giving that a go

 

Thanks for your comments 

 

Dave

[db964]

Hi ndg_2000,

 

I have reinforced the concrete with mesh so hopefully it should be OK... hopefully 

 

Cheers 

 

Dave

[ndg_2000]

Hi

 

I initially started with a circular oven dish filled with sand and it does work 

 

Another option for a heat deflector is pottery kiln shelves they can be bought in different sizes and also circular ones can be purchased and are generally are less expensive than pizza stones.

 

I also reinforced my concrete with chicken wire but still had blow outs but I think that's because the perlite is quite soft. 

 

I will be watching this thread and I do wish you luck. 

 

P.s. The food always tastes a little better when you have built the kamado yourself 

[db964]

Hi,

 

In the end I just used a frying pan filled with sand like you said and it works great  

 

I've had no 'blowouts' which I think was due to welding the mesh to the sides and I left it to dry out for a month in a warm room over Christmas...

 

The smoking was great really leagevthe vents almost not even open and it keeps a temp well, as long as you slowly increase the temp till optimum.

 

And the pizza oven used it last night and the pizzas are restaurant quality  

 

Thanks for your help

 

 

 

[keeperovdeflame]

Wow, you got some skills, brother. In case of  an apocalypse, I want to live next door to you. Amazing project, whether it holds together or not,  I could not do that, even with a whole lot of help.