Loft Block Idlers
Idlers may be added to underhung loft blocks to carry the weight of the cables and prevent rubbing against adjacent block side plates. They are not intended to carry line loads or to act as deflector or mule blocks.
Idler assemblies consist of one or two 3-1/2 inch (88.9 mm) diameter, 3 line nylon sheaves mounted on the side of the loft block in a steel housing.
Idler sheaves have 1/4 inch (6 mm) cable grooves with a 3/8-inch (9.5 mm) shaft in a 12-gauge steel housing with two 1/4 inch (6 mm) bolts and pipe spacers to mount the housing and captivate the cables in the grooves.
When using idler pulleys, the loft block closest to the head block should be a full size multi-line block with grooves for all of the lift lines. This ensures that fleet angle and other alignment stresses are not transferred to the idler pulleys.
Add Idlers to 8″ (203.2 mm) Underhung Blocks - change last letter to “I3″,”I6”, or “I9” to indicate 3, 6 or 9 idlers.