Tail Construction 100% complete

Building the tail is the easiest part of the airplane so it's a good place to start for a confidence builder.  The tail structure's strength comes from the welded tubing frame with plywood ribs glued in place to make the tail surfaces aerodynamic.  The instructions with the kit are excellent, like a big model airplane.
The first step, shown here, is to epoxy in the airfoil shaped plywood ribs into the welded frame. 
The second step is to install the bearings which hold the elevator on.  The bearing is constructed of a bronze bushing glued into the elevator and a steel bearing which slides inside the bushing.  Shown here I am press fitting the bronze bushings into the elevator and attaching it with locktite 680, an industrial locking compound.
Ran into my first problem on step three.  The steel bearings for the elevator were not long enough so that when the nuts were properly torqued, the metal hinge tabs ground on the ends of the bronze bushings - too much friction. 
To solve the binding in the elevator hinges, I turned six new bearings of the proper size on my lathe.  From steel bar stock, I turned to the correct outside diameter then drilled the hold for the AN3 bolt to pass thru, then cut the bearing to length.  A lathe is really a necessity in aircraft construction in my opinion.
Rather than leave the ends of the elevator and horizontal stab unsightly tubing, a nicely rounded tip is formed using styrofoam, epoxy and micro-balloons.  Here it is shown after sanding. 
The horizontal stabilizer is held in position with two struts, the attach point needs an access box.  To make this box requires fabricating the sheet aluminum bracket shown, drilling it, and riveting/epoxying it into position.  The diagonal piece in the picture is the strut going down to the fuselage.
Here the horizontal stabilizer is test fit into position.  Next, the vertical stabilizer and rudder get their plywood ribs epoxied into place just as on the horizontal stabilizer.
The electric jackscrew used for the elevator trim is installed.  This was a big job and required some modifications to get it to work perfectly.
Because of concern from others who have built this plane, I reinforced the motor housing to insure that it would not break from fatigue.  Again, the lathe was indispensable in building the reinforcement bracket.
The up/down trim switch is installed in the control console along with the trim position indicator
Here, all the ribs are installed and I am setting the control deflections.  The maximum up deflection is 39 degrees and the maximum down deflection is 20 degrees, setting this precisely is important for the safe handling of the aircraft.

 

 

 

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