My pleasure Mark, I tried to take the pics to be a dummy guide
I need a manicure 

I did dig up a hex head wrench but honestly haven't had to use it. I've been able to grip the hex head on the screw tight enough to turn it and punch cartos just using my fingers![]()
The normal set screw collars didn't work because the wall thickness (the part the set screw goes through) wasn't large enough. The hub, with about an 8-9 mm wide body, has enough room for the screw to get some bite, even with the point on the screw.Did you consider using those Drill-stoppers where you screw a nut into the drill-bit?
Looks like a great idea. I just ordered the coupler body.
If anyone has ordered the screws in bulk, I'd like to buy some from you. Please PM me.