We have been building a smoker out of 55gal drum. We are using a turkey fryer propane burner for heat. We have been able to consistently run what ever temp we want so far. Our snag at the moment is after about 20 mins the wood chunks catch on fire. We are basically going with a gas, cabinet style system. The wood tray is 4" from the burner. I know this mat be a little vague, but any ?'s of suggestions would be vary welcomed. Pics below.