Glossary of Terms

Fiddle Pulley

Fiddle

A fiddle pulley contains two sheaves, one above the other, with one usually smaller in diameter, so it's shaped like a fiddle. They are used to build simple 3:1 or 4:1 mechanical advantage systems. The large sheave/small sheave configuration prevents rope chafe for a low-friction block and tackle.

Hardkote-anodized

Hardcoat aluminum anodizing is an electrochemical process that produces a corrosion-resistant finish with hardness characteristics second only to diamonds. Harken’s hardcoating process, “Hardkote,” is twice as thick as black anodization to provide extra protection against scratches, dents, superficial deformation, and corrosion.

Helicoils®

Thread inserts that provide stronger threading for fastener holes, distribute fastener loads over a larger area, and isolate dissimilar metals.

High-beam track

High-beam vs. Low-beam Track

High-beam track has a taller profile than low-beam track. Use high-beam track in carriage systems that span unsupported areas with the track.

Holding power

The ability of a ratchet pulley to hold a static load. Expressed in a ratio of force on the loaded side of the rope to force on the side of the rope exiting the block, holding power is especially useful for relieving loads on hand-held ropes (when the block is not turning).