Hi David
Hows Oz, traitor

I use straight diesel oil, for good smoke it's not so much the fluid but how it's introduced. You need large volumes of oil my model uses 2 liters in 4 to 5 minutes! I pump the oil into a 4mm brass tube with a turbine pump. the end of the tube is flattened to give a fan spray. The system is so responsive you can draw dots in the sky.

Mick