If you drilled into the mast this method would even work better.
Subject:Re: [TowerTalk] HAM IV rotor / mast slipping / Slipp-Nott
Date:Fri, 6 Apr 2012 23:27:51 -0400 (EDT)
One simple (and easy/cheap) thing to try:
Drill and tap the clamp plate for 4 additional 3/8" pinch bolts/screws
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
down from the top edge and 1/3 of the way above the bottom edge. If the
plate is too thin for enough threads add a surface welded nut to the outsied
Unless you mast is super hard material, having 5 pinch screws should go a
way to keeping the mast from rotating.
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