Ingredients

Most explosions start with black powder. Composed of a variety of materials including charcoal and potassium nitrate, black power comes in a variety of forms, from powder to small chunks. Typically all it will do is burn when lit, but if placed in more compact conditions it can create quite an explosion. How it is prepared depends on how it will react. It is typically placed in plastic or cardboard containers; the tighter it is compacted and the thicker it is wrapped with tape the more violent the explosion will become.

By itself black powder does not create much of an interesting show, so different types of metal can be added to cause differing colors, much the same way fireworks are created. To give the effect of debris flying in the air soft materials such as peat, cement powder or pieces of foam are added on top of the black powder. Upon detonation these are then thrown into the air; caution must be taken to prevent any stones or hard objects from being placed among the debris to prevent them from turn into a potential bullet if propelled through the air.

To create explosions with fireballs a variety of liquid fuel is used. Most commonly used is regular gasoline, which makes an orange flame. Diesel is used to create a redder flame with black smoke on the fringes. Both of these continue to burn after the initial explosion and may fall on surrounding areas and continue to burn. Slightly safer is naphthalene and isopropanol which burns and finish after one explosion. Naphthalene gives a look between regular gasoline and diesel. Isopropanol is pure alcohol and creates a cooler flame that can be used indoors and closer to actors.

All of these ingredients are placed in mortars, which are steel tubes or pans in a variety of shapes that help direct the blast. While a round tube will blast objects straight into the air, a wider pan will spread the explosion outward. The black powder is placed on the bottom with a detonator chord attached to it. Next a bag of fuel is placed in the mortar with any debris material placed on top of that. Last is a second detonator at the top of the mortar to ensure that the fuel catches on fire.