by Bryan Cotton » Tue Aug 02, 2016 11:12 pm
Here is my tooling. The thick piece guides the drill on entry. The hole is bored to 1/4" all the way through, then 5/16" down to within about 1/8" from the bottom of the hole. The little piece is for the drill exit.
Here the tool is clamped in place. I put a 1/4" rod to align the pilot hole in the fuselage with the tooling.
Here is the back side.
The 5/16" bit slides into the entry tooling for nearly an inch before any drilling takes place.
Of course I drilled the tooling holes on the drill press. Adam worked the aft spar mount while I did this - a bunch of updrilling and deburring.
Bryan Cotton
Poplar Grove, IL C77
Waiex 191 N191YX
Taildragger, Aerovee, acro ailerons
dual sticks with sport trainer controls
Prebuilt spars and machined angle kit
Year 2 flying and approaching 200 hours December 23