Mother Earth: Waste Oil Heater
Babington Burner
Those two ought to give you some ideas. I once tried the wood stove thing with a 24 by 32 garage and its just too cold here in the anus of the planet to have the slow heat do its thing. You need more heat faster when you need it unless you are staying out there all day and not opening the garage door. I now use a simple infared radiant 35K propane heater (coleman) that mounts right on top of the barbecue bottle . I like it since it can be put right behind you and keep yer whatever warm even outdoors if needed with no electricity. Yea I know its shitty propane but sometimes the convenience and just plain raw heat production outweighs the price considerations.
Another thing with wood stoves is that they are illegal by nat code for use in a garage where cars are stored. Not that I don't do worse every day but its pretty hard to hide and deny a wood stove if the place burns down. Of course insurance companies are famous for denying claims for things when something else not related caused the fire if they can find SOME reason. A wood stove is sort of hard to make dissappear after the fact. I spray paint sometimes and of course you can't have a flame running or might wind up pushing daiseys there too so again I like the propane as you can shut it off then restart it again after for quick reheat.
One thing you might try that worked for me is plastic sheeting. Drape off a small section of your garage where you park with plastic sheeting. You can suspend it from a rafter or rail and drop it as needed something like a home made paint booth. That keeps the heat in pretty well and doesn't need much to maintain. Winter sure sux doesn't it. Worst of all thats when most of the car stuff goes to hell.
