Knives

Knives that produce bloody wounds can be constructed in the same fashion as the dagger explained on page 130. Similarly knives that appear to have been thrown can be constructed on the principle explained for spring-up arrows on page 126.

Compressed air knife thrower

A knife with a cylindrical handle can be fired from a ‘gun barrel’ tube by propelling it with compressed air. It can be fired with considerable force and accuracy and may be safely used to stick a knife into woodwork within inches of an actor. Needless to say, all sensible precautions should be taken. The gun must be rigidly fixed and should be provided with an efficient sight. Correct air pressure must be determined by practice shots and maintained thereafter.

Two important factors are the length of the barrel (about 5ft is nominal) and the air release valve which should be of a type that permits full air-pressure to be applied with a minimum of delay.

Knife-throwing act

This is a board in front of which stands a beautiful circus girl while her partner throws large knives or hatchets around the perimeter of her body. In the event of there not being a skilled knife throwing artist available, the effect can be achieved by using spring-loaded knives which flip up from out of the board itself. The board, covered by a thin sheet of foam-plastic, has slits to permit free movement of the knives, the handles of which should be as thin as possible. A garish design on the board camouflages the slits.

The knives can be released by solenoid catches operated remotely.

Care must be taken that the performer does not move out of position because the knife handles can deliver a powerful blow.

Safe knives

Knives cast in latex from plaster moulds may be used for fight scenes where safety of artistes is important.

KNIVES

1. Compressed air knive thrower
a, Foresight, b, Backsight, c, Knife, d, Compressed air. e, Operating valve.

2. Knife for compressed air thrower
a, Piston washer, b, Cup washer. The scale is indicated above (1). The ‘barrel’ of the thrower is generally about 5ft long.

3. Spring-up knife
An alternative method is to conceal a flat dummy knife in a thin slot suitably camouflaged. A spring mechanism flips the knife upward when required.