Rocket heat question

Hi,

I am looking to build a portable Rocket heater that can be moved from garage to shop.
If I use fire brick for burn tunnel base are there any educated recommendations of perlite thickness below bricks so it cam operate on a plywood subfloor?
I want to add wheels to make it like a dolly.

Scott

The main point would be to keep the base above the floor, with at least a couple of inches of free airspace. A couple of inches of perlite between bricks and a metal base to the dolly should give adequate insulation, combined with the airspace.

Glen,

Thanks for the feedback.
To better explain myself I created a sketch illustrating my design. What I was looking for was a thickness of perlite that would protect the plywood base.

Don't use plywood in the base.

It will be easy to protect the floor from overheating with a couple inches of perlite and an airspace, but without an airspace, the heat will eventually build up and char the top of the plywood in your base proposal.

Insulation does not stop the flow of heat, it slows it down, and as plywood has some insulative value, the top of it would get hot unless you used an insane amount of perlite like maybe 6" (just a wild guess). Even then, a burn lasting for many hours might let enough heat build up to be dangerous.

Using wood framing around the edges of the base may be okay, as it will be far enough from the heat source for heat to dissipate in two directions. I would still be cautious, and check it regularly after long burns to see if it is getting hot.