I have a shitload of waste-oil and can get a next to unlimited supply for free, I am sick of being a lumberjack to heat my shop so I think I'm going to build one of these bad boy's. Anyone built/used one before just looking for any feedback on these things.

http://journeytoforever.org/biofuel_.../me4.html#mwoh

 

we have them at work and they work great, except for if it gets really really cold they won't work