On Sep 12, 9:11*am, " wrote:
I am wanting to make some very long hex shank drill bits for a wood
working project that I am working on. *I am having to drill into very
tight areas that I can't get my drill into. *I have some long aircraft
drills that I want to add a hex shank to. *I figured to save some time
I could drill out a hex coupling nut but the problem is that the
smallest one that I could find is 5/16 across flats. *Is there anyone
out that sells smaller coupler nuts?

I also thought about annealing a hex key and drilling that out.

Does anyone have any other ideas?

Any help would be greatly appreciated. *Thanks

How do you plan to attach the bit firmly enough into the hex coupler?
Some of the makers of hex shank drill bits haven't quite figured that
out yet. I made a narrow extension holder out of a hex-head bolt which
has enough metal in the head to hold a setscrew.

A small drill chuck on a hex stem that might work. You can make your
own drill bits out of 3' long drill rod by grinding a cone for the
point and then grinding a flat on one side that reaches the center.
Looking from the end the drill bit is D shaped. You have to remove it
frequently to clear chips.