Technical Design Solutions for Theatre

A Swivel Caster Bolt-Hole Jig

Bonnie McDonald

FIGURE 1: PICTORIAL

FIGURE 2: CASTER SWEEP CLEARANCE

Tired of spending too much time tracing bolt holes for stock casters? Try this simple jig, commonly used at the Santa Fe Opera, and your tracing days are over.

CONSTRUCTION

Place the caster upside down on the steel plate. Rotate the caster on its base, and mark both the wheel’s sweep and the caster plate’s bolt holes on the steel. Next, around the sweep circle, draw a square whose sides are ⅛″ larger than the sweep circle. See Figure 2. This larger ...