I have been told that the nails can fly out use a safety shield and make certain the nails are not pointed at anyone. A lazy susan is fitted with a tall tube of screen door screen. A cotton ball soaked with lighter fluid is placed in an evaporating dish duct-taped to the center of the lazy susan. The ball is ignited. This was supposedly used for one of the special effects in Raiders of the Lost Ark when the Ark was opened by the Nazis.
Lighter fluid makes a good fuel because it burns with a strong yellow flame.
I have heard that non-dairy creamer works well here. You might need to microwave it to make certain it is very dry. We used to simply flick this through a flame with a spatula to get a large flame. We have also used a glass tube attached to a bulb to throw the powder through a flame. We have a tank of oxygen we use to fill the jar.