wall thickness

[peter61]

What is the minimal distance between walls(outer+inner) on a 32"x32"x72" oven for a safe and functionable oven,the oven is made with 20 gauge steel+steel studs,thanks in advance.

[CarWiz]

It depends on the insulation used, if any. With some of the ceramics, wall thickness can be 1/4" with a 1000 degree oven and you can still stick your bubble gum to the outside wall. Price = Performance when it comes to insulation.

Most new home heaters and water heaters are rated "Zero Clearance". This means that the outside wall will not cause ignition of building materials. That doesn't mean you can put your hand on it though. (Although some meet that test.)

[FigureLLC]

i used 25ga 2x4 studs, with the wall thickness being the 4" dimension. the insulation i used was R15 fiberglass insulation from home depot, with the kraft backing removed. it does a good job. when the oven is up to temp for extended periods the walls get hot at the studs. if that's a problem for you, search the forums on here for how people have insulated the studs from the inner and outer walls.

[PhredAre]

On my Oven, I built a box within a box. I used 3/4" sq. tubing with a total wall thickness of 4". The inside box only contacts the outside box at the door flange and the back corners (top& bottom for support).There is miminal heat effect on the outside. This is not unlike a large utility boiler is skinned. I used 4" rock wool insulation which seems to work quite well. I welded nails to the interior side of the the tubing to hold the insulation in place. I skinned the oven with gal. sheet metal using self threading screws. There is a picture of this Oven on a previous post. Good luck, Fred

[asallwey]

Fred,

Might you have a picture of the walls showing how you connected them?

Alex

[PhredAre]

Sorry, no pictures. The War Dept (wife) said I should take a few when I was in the process of building this oven, but the construction was labor intensive and I was in no mood to take pictures. The results in the end were worth it in my opinion. If you were here in western WA you could just come and take a look. If you were interested in pursusing this method on construction I will try to help you get started, I can take a skin off the outside an take a couple of pics and supply you with the particulars of construction. This design is more costly than metal stud costruction, like everything, there are trade offs. Fred

[peter61]

Does anyone know where to get regular conventional oven insulation?It seems like thats what I'm going to need,the distance between my 20 gage steel is only 2",thank for all your help.

[FigureLLC]

Originally Posted by peter61

Does anyone know where to get regular conventional oven insulation?

the old kitchen oven i used for donor parts had yellow fiberglass insulation, to my surprise...

[pcer]

ok, i was at home depot last night, they had NO R15.............i ended up getting R-19 that is 6in thick and NO backing on it.........it was $28 bucks, with plenty to do my oven build.


They had some High temp insulation, in thickness up to 2", it was in these 4x8 sizes, and it looked kinda like styrafoam. they tried to talk me into it, but i knew nothing about it and i had heard R15 worked so for sure R19 would.

But someone DEFINITLY needs to check into that other stuff, come to think of it, 2" walls would be nice.

[asallwey]

PhredAre,
If you have the time to take a wall off I would appreciate a pic of the construction. Or just a description (but a pictures is worth ... )
Alex