The Torsional Stiffness Apparatus incorporates a torsion head and wire that translate a twisting motion to a 1/2" wide x 4 1/2" long specimen. Mounted to a rigid base and support post, the torsion head includes a dial protractor graduated from 0 to 360°. Made of 0.010 inch diameter tempered stainless steel wire, the torsion wire passes through the center of the torsion head in a loosely fitting sleeve gripped by a friction bearing. A fixed index pointer indicates the degrees of twist introduced to the torsion wire.
Specimens are secured to the Torsional Stiffness Apparatus by two clamps. The upper specimen clamp is fastened to the lower end of the torsion wire and is able to rotate as the torsion wire is twisted. The lower specimen clamp holds the specimen in place which allows the twisting action to occur. To accommodate the twisting action, the lower specimen clamp can slide up or down guide posts mounted to the base.