Tips for Rigging with Eye Bolts

ubal, an entertainment rigger from Local One IATSE and recent safety webinar attendee, asked the following rigging question about eye bolts:

Is it necessary to use only one washer when securing eye bolts or can the washers be stacked if necessary?

Peter Cooke, Columbus McKinnon Training Manager and Safety Webinar Presenter, answers:

If more than one washer is necessary, the eyebolt may need to be turned to align with the rigging. Please see the example below.

A shim can be added to reposition the orientation of the eyebolt. Most importantly, you must maintain proper engagement or tightness. A shim can vary in thickness depending on how you need to align the eyebolt, as when a 3/8  eyebolt with 16 thread per inch is used.  With 16 threads per inch, one turn would relate to .062” of movement into the mounting plate. If we divide this by 4 to get .0156” for our shim, the result will be a change in rotational position of the eyebolt of 90 degrees, which can be used as a reference dimension for adjusting the spacer on the eyebolt to achieve the proper orientation with the load.

Want to learn more? View our recent safety webinar!