The Basics of Setting up a Fireworks Mortar Box

filling fireworks mortar boxes

Mortar Boxes

What is a mortar box?
A mortar box is exactly what the name states. A box your going to fill with mortars.

Each box, consists of two long sides and two short sides, which form a frame with no top or bottom when assembled. These wooden frames are assembled using metal rods, washers, and cotter pins, then filled with sand.

These boxes are usually only used on the 4th when there are simply not enough racks to go around. Sand boxes take much longer to fill than it takes to cleat an equivalent number of racks.

Another reason mortar boxes would be required is if you are shooting out of steel tubes. By law, the steel tubes must be buried 2/3 of their length in the sand in case of a tube fragmentation.

How do you assemble a mortar box?
Very simply actually. Take the two small sides, or ends, and slide them in place between the two long sides.

There are six holes for the rods which hold the boxes together. Insert a rod through both sides, put washers on both sides of the rod on the outside of the box, and secure using the cotter pins. Watch our video explanation of mortar box assembly.

Training Video!

Mortar Box Assembly

completed fireworks setup