January 20, 2021
A fairly common problem that builders run into is the clearance for the bolt head on the control horn for the elevators. If you set the distance from the forward spar of the elevator to the center of the rod end bearing to 13/16" like the plans show the hole that you drill into the control horns may come too close to the weld and you lose the clearance for the bolt head.
Well I didn't figure this out until after I had already drilled a small pilot hole. After much thought and consultation with others I finally decided that I would move the hole. The problem is that the hole won't move far enough to be another hole. When drilled in the right place it will intersect the existing hole.
The way that I finally solved this was by first readjusting the rod ends to move the elevator further away fromt the HS. I think I wound up with about 7/8" Then I got a piece of thick walled 1/4" tubing and drilled the inside out to 1/8". Then I put my little Dremmel tool high speed cutter bit into the tubing and put the tubing through the center hinge on the HS. Since I was using a cutter instead of a drill bit I was able to mill another 1/8" hole in the control horn that intersected the existing hole. This made a figure 8 looking hole in the control horn. Now how do I enlarge this to 1/4" without destroying it or the drill bit.
I drilled a 1/8" hole in a piece of steel angle and using a 1/8" drill bit as a guide clamped the angle to the control horn. Once I had it clamped down tight I drilled the hole out to 3/16" then to 1/4". The steel angle kept the larger drill bits centered on the hole that I wanted and kept them from trying to follow the other hole or breaking the flutes of the bit. Once the hole was enlarged to 1/4" the original hole was swallowed up and it looks like I did it right the first time.
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