Originally Posted by
illwafer
have you done this before? it looks like there isn't much material in the dropout for drilling right there.
Sure have dude. I studied production engineering (machining, welding, basic engineering principles etc) back in the day.
That's a 118 degree radiused set screw so it's actually only an M6 thread behind it, just radiused so it's a flush fit. The thread is tapped well within the margins of the drop out which is about 4mm-5mm thick steel. The screw really only locates the claw on the drop out, the axle is what actually clamps it into position.