[zippy1]

Originally Posted by Jeff in Pa

Buy an inexpensive wrench and belt sand / grind it the same thickness as the nut. Use it on the bottom ( against the plate ) and use a normal thickness wrench to tighten the other nut to jam it as designed by the factory.

Nylock will eventually work loose ( I tried them and they worked for a year ). You may have luck if you can find the mechanical lock nut that are "squeezed" on three sides.