eh...waste oil burners...
I use 2 55 gallon drums converted to wood stoves,one is an "upright" version that top loads,and has 3 -2" pipes that go down from the top of the barrel to let in air for combustion (a copy of the "Tempwood" stove )--its much safer and you can cook on the flat top of the stove,something thats difficult to do on the other one,thats made into a stove using the commonly available kits at hardware stores..or by using a cast iron chimmney clean out door and a hinged flap for air intake..the toploader sucks to empty the ashes and nails..have to lift them out the top!--but you only need to do it once a year,its not that much of a pain..takes up less space too!.
Sparks can jump out of the air inlets on the horizontal stoves,also any gas vapors will tend to stay near the floor,and could be more easily ignited if any fuel is spilled in the shop..while the vertical "upright" ones pipes could be ducted to outside air if desired to prevent such a scenario..I've never had any troubles with my stoves while working on a vehicle,though while rebuilding a few carbs some gas and vapors were worrysome..but no explosions or fires..(yet
)..
I like the "Mother Earth News" waste oil burner..but its basically just a wood stove with a copper tubing wrapped around the stove pipe with oil dripping on a hot iron surface..I have burned waste oil in my stove for many years by simply letting oil drip the same way on some old tire chains mounted inside the stove near the stovepipe outlet--they get red hot from the wood,and the oil flow is adjusted b a needle valve,makes a "POOF" every time a drop hits the chains..
I've also just poured a cupfull at a time in the stove,as long as you have a good draft,it burns cleanly with little or no smoke..takes all day to burn a few quarts though,in a waste oil "drip" setup....too slow if your trying to dispose of a lot of oil quickly,like at a "real" shop..
Two or three things I dont like about the waste oil heater--not many "good" water heaters are in the dump!..every one I've seen was junked for a reason--IT LEAKED!!...so good luck finding one--whereas one used for a woodstove is easy to weld a patch on..also,21,000 BTU's isn't squat!..(5,000 btu's is what those electric "ceramic" heaters put out..makes a good handwarmer,thats about it!)...
It would do little or nothing to help "heat" my garage--both the stoves I have put out over 150,000 btu's,and at 25 degrees I'm lucky to get it 50 degrees or warmer with BOTH stoves going!(uninsulated steel quonset garage,20x40 ft,13' ceiling)..also I dont see any way to control the oil flow,or shut it off??..and some new synthetic oils won't burn good period..one gallon of it mixed with 54 others of plain petrolium oil will gum up the works..
I think I'll be looking for some water heaters to replace my barrels when they rot out,since they say they are thicker..I get free pallets from factories and places that sell gravestones,and dead trees from the woods out back..
I have yet to ever pay for heat,despite the fact I do have an old forced hot air furnace I had to weld up the cracked firebox in --came from a friends house--its 110,000 btu,sworks great--but I can torch 20 bucks of fuel in it in one day..more than I'd make farting around in the shop--so I stay in the house a lot when its cold!..
--or spend as much time feeding the stoves as I do working..
