Awesome job on the coils and your jig!
BTW, didn't mean to steal your thunder by posting the calc link. As I price the larger air coil inductors in the $20-35 and higher range and consider the prospect of buying numerous inductors for several upcoming speaker builds, this starts to make sense for the adventurous soul.
I wonder if adding a crank handle to the wheel of your coil winding lathe could make the process a bit easier and serve as an index to help keep track of the turn count. And if you were going to do more than just a couple inductors, I bet a turn counter could be added to the rig. After that, just slap a
DRF Electronics Inc label on and start selling those puppies online!
Once again, great job!