Brief Description: Fabricated drill guides of drilling rear spars.
Van's manual recommeded fabricating drill guides out of 1" thick aluminum or steel bar to drill the rear spar sandwiched between the connecting fuselage fork when mated. There are no straight lines to eyeball the drilling of these holes and they must be drilled perpendicular and with a good 5/8" edge distance on all sides of the 1.5" x 1.5" rectangle created by the fork. This is a critical joint and must be done right. You don't get a second chance!
I ordered three 1 1/2" x 1 1/2" x 1" thick pieces of aluminum bar from a local metal shop. I used the drill press to drill the first guide with a 1/8" hole to be used as a pilot hole. I then drilled the second guide with a 9/32" hole to be just shy of the 5/16" final size. The final guide was reamed using a 0.3120 reamer to create a snug fit for the 5/16" bolt.
I'll use a c-clamp to hold the guide and the spar sandwiched between the fuselage fork. My Makita cordless 3/8" drill will be very close to the fuselage and the chuck almost touching the fuselage while drilling the holes. It will be very tedious.
