Brief Description: Final up drill of wing attach blocks and angles.
I talked with Kerry from Sonex and I am going to follow the plans and use the McMaster-Carr 2Step drill bit. My concern is that the AN6 bolt measures .371 and the drill bit is .375. I will think about machining an AN7 down to .375 if it becomes neccessary. for now I bought some 3/8 rod from Fastenal. The rod is .375 inches.I also dulled the1/4 inch pilot on the 2 step bit by dtrilling several holes in a cinder block.
After checking that everything is still level, l I started up drilling the left wing first. I cut on the slower speed and reversed the bit often to remove and clean. In probably 4-5 minutes I was through. The hole looks perfect and the 3/8 rod had to be tapped in with a mallet. I Then installed the aft spar tunnel and aft attach angles. I will back drill through the aft attach angles tomorrow and that should be a breeze. I inserted the step drill and it lands right in the middle of my pilot hole in the aft spars.
This is how you ruin a $60 bit. Dulled the first 1/4 inch so that it will work as a drill gui. .
Forward attach angle and pin.
Aft attach angle with pin visable. I'll back drill these tomorrow.
