Homebrew PCBs

Just want to let you know the idea with the screw works well.

A M10 nut soldered to a short piece of tubing, and on the other end a  
washer.
The drill bit is inserted through the nut, with business end forward so it  
sticks out the washer.
Then a screw is turned into the nut to push the shaft forward.

I made a second screw with a 3mm stud on the tip, which is used to push  
the drill shaft out of the ring all the way.
For putting a ring on a previously empty drill it is helpful to make a  
screw with a hole in the tip, to hold the drill.
The screw is large enough so you can just turn it with your hand and  
overcome the friction of the ring.

Build time: 30 minutes.
Drawback: can not put rings on drills bigger than the standard shaft  
diameter, as the ring does of course not go over the sharp end. I will not  
want to exert pressure on the business end even of a big drill as it will  
surely break. not a problem as i drill them mounting holes with another  
drill anyway where the rings are not needed.

Possible modifications:
If you use a thread coupler (long nut) instead of the nut and tubing you  
have less work to do. i had none that size.
Soft solder is enough strength-wise. If you have a lathe you can make the  
nut/tubing/washer one piece.

ST