Idlers Vs. Multi-Groove Loft Blocks

Multi-groove loft blocks

Idlers vs. Multi-Grove Loft Blocks

Multi-groove loft blocks

Thern Stage loft blocks are convenient to install and ensure a smooth, quiet operation for any performance. These loft blocks have multiple options for customization, including idlers and multi-groove arrangements.


Idlers and Multi-Groove Options: An Explanation

Loft Block Idler


  • Idlers are added to underhung loft blocks to support lift lines as they travel across the stage from block to block.
  • Idlers do not have a load rating because they support only the weight of the wire rope.
  • Idlers may be used when the wire rope path is less than 10 degrees off of horizontal from block to block.
  • If the rope path exceeds 10 degrees, idlers are not the best solution. In this case, a multi-groove loft block provides proper wire rope capacity and guiding.

Multi-Groove Loft Block

Multi-Groove Loft Blocks:

  • Unlike idlers, all grooves on a multi-groove block are load rated for the application.
  • They provide greater flexibility in rigging design, especially in unique and challenging facilities.
  • Idlers are usually 2” to 3” in diameter, spinning many times faster than standard 8” or 12” loft block sheaves. This speed introduces more friction and noise into a rigging system.  Multi-groove loft blocks provide near silent operation with lower friction.
  • The cost difference between these loft blocks verses those with idlers continues to decline.  Idler blocks require additional bearings and parts, and extra time to assemble.
  • Multi-groove loft blocks provide the highest quality solution by offering more flexibility, less friction, less noise, and superior performance.


Thern Stage can provide either loft block style to meet your rigging needs.  Contact a sales representative for more information.