[TowerTalk] HAM IV rotor / mast slipping / Slipp-Nott

[dotravel at aol.com]

One simple (and easy/cheap) thing to try: 

Drill and tap the clamp plate for 4 additional   3/8"  pinch bolts/screws and use the hardened  type with the concave tips. Space the bolts in two rows located 1/3 of the way in from the from each side edge and about 1/3 of the way down from the top edge and 1/3 of the way above the bottom edge. If the clamp plate is too thin for enough threads add a surface welded nut to the outsied of the plate. 

Unless you mast is super hard material, having 5 pinch screws should go a long way to keeping the mast from rotating.  

John NA6L