Calculate complex vector forces easily

Redirect pulley friction

RigRite is all about vector forces and it turns out vector force analysis is the best way to see the effects of friction on redirects/directionals.


As the rope is hauled up through the pulley in this diagram the pulley will rise up because of friction with the rope. The more friction, the more it will rise so a carabiner will rise even more. A perfect pulley would not rise at all, the rope would just run through it.

As the carabiner/pulley rises the redirect angle changes and we can measure this effect with RigRite.

Redirect with RigRite

In the RigRite Directional diagram the grey line represents the resultant vector, if the device was a perfect pulley it would sit on this line. By moving the blue directional line to where the device really sits you can see the effect that friction has on your output force. In this example we are having to haul 106% of the load weight because of redirect friction.

Send Feedback

Related Posts