Building a wood burning "camp" stove for my shed

Question

I am building a small wood stove to heat a 200 sq ft area. I am just wanting to confirm that I have all of the basic components, I will be welding it myself out of 1/8" mild steel sheet.

It will be a simple box, but I will add a small rack on the bottom to keep the hot coals/embers off the bottom, and there will be a false metal "roof" (proper word is baffle as per an answer), not as long as the inside, but to keep heat and sparks from going directly up the outlet stack. It will have a door, with a seal, and I will cutout underneath the door, some holes for air. I will have something that can be slid back/forth to cover/uncover the holes which allow air in.

The outlet hole for the flue gas to escape will be 3.5", and I will put a collar around it of 4" or maybe 6", to attach a stack to.

So in summary, it is a box:

• the metal is 1/8" thick
• has internal cover (Baffle) blocking direct exit of sparks/heat into the stack
• has rack on bottom to keep heat from being directly on bottom metal
• has inlet holes for fresh air
• has seal on door so smoke can't seep out front.

I won't be trying to get this certified, it is just for my own use. I just want to make sure I have covered all of the basic necessities. It would be a shame to make it without the baffle for instance. This question is to catch anything else I may have missed. Is 1/8 thick enough, or should I go 3/16"? In particular, is 1/8" thick enough for the top of the stove, or will it warp?

Answer 1

• You want enough space on the bottom to allow for a layer of ash (and/or firebrick) to insulate the bottom, per standard woodstove construction.
• Your air inlet should probably have a screen as sparks can fly out an unscreened opening there.
• A baffle is not the same thing as a spark arrester.
• Warpage depends a great deal on whether you overfire it or not. Plenty of "barrel stoves" have been built from far thinner material, but they do wear out, especially if overfired frequently.

These are cast iron, but the Shakers did use very small stoves so might be worth looking at.

Modern design insight suggests an area of insulating refractory (where the wood won't hit it - the highly insulating stuff is fragile, while the hard stuff is not highly insulating) to get more of the "smoke" to burn, rather than sending more heat and creosote up the stack.