I'm building a 4x4x8 foot oven, and plan to use metal studs for several reasons.

This will allow a cavity for insulation. I'm using 4" thick rockwool safing bats, cut to 48"x24" sheets. They compress to 3.5" nicely.

I'll be constructing it on 24" centers-with a few pieces of angle iron placed in for a roll shelf and hanger support-

My concern is this-
the outer shell will be screwed to the studs-
this leaves a small area aboout 1/8" thick where there is no insulation-rather a solid conductor from top to bottom in the center of each "wall"
I think I'll end up with a very hot spot there-

The rockwool will but up on each side of it, however it is this "solid" metal area which bothers me.
All of the people with this design oven say "It works great!"

I still question this though--



In your opinion will it be hot to the touch? If it is, this means a safety concern, not to mention a waste of electricity.

Any other ideas to build a secure frame with a surrounding cavity?

It would be twice as much, and probably overkill, but you could do it the same way our house is constructed.

We have a staggered 2x4 wall. This is just a 2x6 wall with 2x4's staggered inside of it. This way there is no direct conductor of heat to the outside.

Here is a picture that gives a good visual of what I mean:

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While I don't know anything about what you're doing, I am thinking since it works so well for house construction, it should work well for this, as long as it isn't cost prohibitive.

I dont know how big your voids are, but, why not use a fire proof putty. Fireproof putty is typically used on a 2 to 4-hour fire walls to seal voids. I dont know the exact specs or brand.

I'm building a 4x4x8 foot oven,
What are ya cookin'??? :bounce:

Could you use longer screws and some sort of thick insulating material between the studs and exterior? The screws would still be hot, but the exterior wouldn't be in direct contact with the studs.

Time to go browse through the insulation section at the home improvement store of your preference.

What are ya cookin'??? :bounce:

Need a big wedding cake?

Like this:

http://www.adlinsulflex.com/heat-resistant-tapes/silicaflex-tape-ab/

What are you covering the inside and out side of the structure with?

If I am picturing this right you are concerned with the metal studs allowing the heat to transfer to the out side of the frame along the studs.

What about this idea. I assume you are using a steel track at the top and the bottom. Instead of screwing the studs to both sides of the track like in a normal wall. Turn them 90 degrees. Screw one to the inside of the track then go 12" and screw one to the outside channel. then just keep stagering the studs every 12" For the corners get a stud with a short web side to allow an air gap. With the studs so thin just put a slit in the insulation to allow it to fit around the studs. This way yow will not have one piece of metal touching both the inside and the outside walls.

Not sure how to draw it so I hope that makes sense. If a 3 5/8 stud is to wide this way you can get them thinner or wider.

What are you covering the inside and out side of the structure with?

If I am picturing this right you are concerned with the metal studs allowing the heat to transfer to the out side of the frame along the studs.

What about this idea. I assume you are using a steel track at the top and the bottom. Instead of screwing the studs to both sides of the track like in a normal wall. Turn them 90 degrees. Screw one to the inside of the track then go 12" and screw one to the outside channel. then just keep stagering the studs every 12" For the corners get a stud with a short web side to allow an air gap. With the studs so thin just put a slit in the insulation to allow it to fit around the studs. This way yow will not have one piece of metal touching both the inside and the outside walls.

Not sure how to draw it so I hope that makes sense. If a 3 5/8 stud is to wide this way you can get them thinner or wider.


I think I understand-
I would screw into the face of the stud instead of the edge when installing the liner panels.
(which will be made of aluminized metal sheeting.)
In answer to an earlier question-the seams will be sealed with stove cement.


I think that may work by golly
I'm going to look into this. Thanks

Thats the only way I can see not having metal to metal contact all the way through the outer walls and still keep them 3 5/8" thick. The only down side I see with this is you now have 3.5" instead of 1.5" of stud touching the inner walls. It will have more surface area to transfer heat into the wall.

What about doubling up the insulation and get some 7" or so wide track then just build the walls like posted above. Thicker walls but more insulation.

I think it will work fine--here's why
I already have a sheet of metal inside and out-
the 3 5/8 stud won't make a difference. The insulation can now be seam taped into one solid piece.
I can cut slices into it to fit tight against the studs, along the protruding edges.

Sounds cool Post pictures of the build up and final product.

I think 5/8" wonderboard cement boards would be a good idea to use.

I was going to say cement board as well for an exterior, may get costly though. Not sure the going rate on it anymore, but know it usually only comes in I think a 3'x5' sheet.

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For those who care this is also an excellent way to not let sound carry from one room to another because the drywall is not screwed to the same board on both sides.

The cement board for 5/8" is approximately $15 a sheet.

I agree hardibacker is a great product-My bathrooms are constructed with it, and I used it for my sub flooring as a tile base-

However-not on my oven. It will be all metal--

I'm following this as a guide-

http://www.f-5performance.com/powderoven.htm

and I want to incorporate a shelf-and trolley like this one-

http://www.powdercoatoven.4t.com/

Hardibacker is not cement board even though it says cement board on it. I'm looking at 6 pieces as I type this. It's some sort of fiber material. Did you consider using cinder blocks or bricks?