Tips and Tricks

Post Control Horns That Look Good

GENERAL - In larger planes the control horns I like are the 10-32 bolts with the hanger 9 fittings on them.  The problem is that the head of the bold shows on the top of the aileron and that the bolt is best put in hard points to prevent crushing the balsa used for the leading edge of the aileron, rudder, or elevator.
Well I have a solution that is easy and looks real nice

As you can see above the upper side of the ailerons and of the elevator show no trace of the mounts while the underside of the elevator has the posts securely mounted.  This is a nice installation

FIRST -- lay out the location of the posts and drill ½” hole through the surface using a sharp drill bit or a spade bit that has been ground to the perfect size.  This drilling must at the correct angle so that the posts are vertical when the surface is centered. To do this, put the surface back in the foam shuck it came in and the alignment will be just fine.

SECOND -- Size and white glue in a hardwood dowel that is ½” in diameter and let it dry.

THIRD -- sand and finish the dowel flat with the surface.

FOURTH -- return the surface to the foam shuck and drill a hole that is just undersized for the 10-32 post, being sure everything is straight.  This is best done on a drill press to get everything lined up.

FIFTH -- now drill a larger hole in the upper surface of the dowel to allow the head of the bolt to fit just below the upper surface.

SIXTH -- Apply whatever covering you wish to the bottom of the surface and then cut a hole in the covering for the bolt. Screw it in from above. Put the nut on the bolt, apply thread lock and tighten it down securely.

SEVENTH -- Fill the hole in the dowel on the upper surface and finish it flat.

EIGHTH -- Cover the upper surface and you are all set.