Chapter 10-12 - Canard, Elevators & Installation

The canard, elevators, and control system were all built and installed by Michael before I started work on the plane.  Of course, when I came along I decided to muck it all up.  First, the canard incidence template had changed over the years, so I needed to be absolutely certain that the canard met the newest template.  Wrong incidence had been blamed for very high takeoff speeds, poor stall characteristics, and in once case very neutral pitch stability despite being in the design CG range.  I knew I wanted this right.  

Using the latest template from the newsletters, I marked off the canard every 12" or so.  The fuselage was leveled with the longerons using a digital smart level, and then I checked the template, marking the canard as I went.  There was very little twist in the canard, and overall the canard was within 0.1 degrees of the template throughout.  That was good enough for me!

The elevator balance is critical to keep it from fluttering, and it was an easy task to use the elevator hinge pins to verify that it met balance.  It was not an easy task to actually have them balance, though.  On my first pass I filled and sanded them, followed by a WEST epoxy wipe, and primed them.  Of course, after all of that they balanced tail down.  What followed was sanding ALL of the primer and fill off, then sanding through the first layer of glass in some spots, per plans.  Then I was able to just barely fill them with micro, followed by WEST and primer.  This time, they balanced.

The only other trouble I had was when I had the plane inspected by Marc Zeitlin for an EAA Technical Advisor visit he noticed a very slight resistance in one elevator.  It was the balance weight just barely catching on the pocket in the canard.  Judicious sanding of the fill on the balance weight and the pocket generated the 1/16" (one mixing stick thickness) clearance.


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