Technical Design Solutions for Theatre

Toggle-Clamp Locks

Richard Gold

 

Handle-action toggle clamps provide a sure and inexpensive means of securing trapdoors in platforms and stage floors. Such clamps are basically locking levers, which require very little effort to open or close and yet offer substantial holding force when they have locked into their closed position.

By attachment to a low-pressure double-acting pneumatic cylinder with a 5″ to 8″ piston throw, an inexpensive, manually operative toggle clamp can be converted into a remote-controlled trapdoor lock. The toggle clamp is easily modified by drilling a hole through the handle and pinning the piston to the handle using a female rod-clevis assembly available from pneumatics suppliers. In-shop modification for pneumatic ...