kiln conversion?

[indyoven]

I just got a old Blue Diamond ceramic kiln and I am wondering if anyone has done a kiln to pizza oven conversion ? I was thinking of a barrel vault design anyway and then came across this. It is 29" inside dia. Im thinking I can use the half barrel shape placed on a base. Does it make sense to do additional layer of fire brick for more heat holding power ? The fire brick the kiln is made with is very light weight compared to the fire brick I removed from a old backyard BBQ. Will the heavier brick hold temps better ?

[Tscarborough]

Re: kiln conversion?

Kilns and ovens do not serve the same function. The insulating firebrick do not have enough mass to serve as an oven, although you may be able to reuse a few as a thermal break to build an oven.

[scott123]

Re: kiln conversion?

Tom, that's not entirely true.

Dumbo NYC, Brooklyn ? Archive ? Wild Rise Pizza Opens in Dumbo (DumboNYC.com)

Indyoven, it's probably pretty feasible to convert a regular into an upside down raku kiln. If you've got the kiln, this is probably the route I'd take.

[Tscarborough]

Re: kiln conversion?

That is a pretty limited and specialized use. I have a 1400 degree heat gun I could cook pizza with if I wanted to, but that doesn't make it a pizza oven.

[scott123]

Re: kiln conversion?

Tom, they happen to be using it for Neapolitan pizza, but you could just as easily use it for NY as well. Between those two applications, I hardly see it as 'specialized.' The output might be a bit of a question mark, but, since they're using it in restaurant setting, it can't be that horrible.

And, as advanced as your pizzamaking skills are, I'm sorry, but you can't make those pizzas with a heat gun.

[Tscarborough]

Re: kiln conversion?

Sure I can, I have.

[Tscarborough]

Re: kiln conversion?

Here is the thing with using a kiln to cook pizzas. It will certainly do it, it gets hot enough. What it can not do is do so efficiently, anymore than my flamethrower can.

[scott123]

Re: kiln conversion?

Sure I can, I have.

You can make a Neapolitan pizza with only a heat gun?

Pictures, or it didn't happen

[scott123]

Re: kiln conversion?

Here is the thing with using a kiln to cook pizzas. It will certainly do it, it gets hot enough. What it can not do is do so efficiently, anymore than my flamethrower can.

A kiln is a fully insulated enclosed box with a heating element inside. If anything, the extra insulation on a kiln would make it more efficient than a home oven, not less.

And, compared to a WFO? You've got no heat going up a chimney here, so that, in itself, makes for much better efficiency.

[Tscarborough]

Re: kiln conversion?

No, the difference between a kiln and an oven is that the insulation is the refractory in the kiln and hence has no mass to hold and conduct the heat. To use a kiln as an oven you have to continue to input heat.

[scott123]

Re: kiln conversion?

Tom, both LBEs and home ovens have very little thermal mass and require continuous heat, and yet both have been successfully used to bake Neapolitan pizza. Are you really saying that the only suitable tool for making Neapolitan pizza is a WFO?

If the kiln is shallow (close to the pizza), you should be able to put just enough energy into the system to pre-heat the hearth and bake the top of the pizza. That, to me, seems to be incredibly efficient.

[david s]

Re: kiln conversion?

Can I chime in here, I've had a fair bit of experience with both kilns and WFO's.
The refractory used in kilns varies from dense firebrick,to insulating firebrick, to hot face ceramic fibre. The kiln you were describing Scott, uses insulating firebrick. They are very light with low thermal mass which means they won't store heat. This is ok so long as you have a continual active fire while cooking pizzas. If you want to close the oven to cook roasts or bread, then your oven will not have enough thermal mass for extended cooking time.

A well insulated WFO has about the same amount of insulation as a kiln. If it is too well insulated you are waiting too many days for it to cool.

The thermal mass in a kiln is obtained from whatever you have inside it. A partly loaded or empty kiln does not fire particularly well because there is less dense material to hold the heat. You can argue about this ,but that's what happens

The other disadvantage with using insulating firebricks is that they are not as strong as dense firebricks and will be subject to damage easily when loading wood into the oven.

I am currently doing an opposite project by making a kiln using some of my oven moulds.Can't get back into it as the rain won't stop. Thinking of building a giant wooden boat instead.

[david s]

Re: kiln conversion?

Scott,
If you plan on using the existing elec. elements instead of wood, be careful to ensure that you still have the door switch operational. A stainless steel peel touching the elements could give you a hefty jolt.

[scott123]

Re: kiln conversion?

The refractory used in kilns varies from dense firebrick,to insulating firebrick, to hot face ceramic fibre. The kiln you were describing Scott, uses insulating firebrick. They are very light with low thermal mass which means they won't store heat. This is ok so long as you have a continual active fire while cooking pizzas. If you want to close the oven to cook roasts or bread, then your oven will not have enough thermal mass for extended cooking time.

David, I agree, a kiln lacks the thermal mass for residual heat cooking, but the OP specifically asked if a kiln could be converted to a pizza oven, not a residual heat roast/bread oven- at least that's my understanding of his/her request. If he/she said pizza oven as another way of saying brick oven, then no, you can't convert a kiln into a brick oven. But you can definitely convert a kiln into an oven that makes pizza, depending on the size shape and how handy you are.

[david s]

Re: kiln conversion?

Ye s, I agree and my apologies, I thought you were the OP. if the floor were dense firebrick, then that would store a fair amount of heat to cook the base and as long as an active fire were maintained then the top will cook ok too. It is also possible to add some thermal mass outside the arch to provide the extra thermal mass, but the heat has to fight its way through the insulating firebricks to get there. I still think dense bricks are a better solution.