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  1. Secure the bolt in the chuck (preferably a collet chuck for a 1/4-20 screw) of a lathe (head end pointing outward).
  2. Using a center drill, create an indentation in the cap.
  3. Using a 8-32 tap drill size (INSERT DRILL SIZE HEREsize 29), slowly drill through the bolt. Use coolant or oil to prevent overheating of the drill bit or part.
    1. During the initial production round, we used a speed of 400 RPM and a feed of about 0.001" per 1-2 seconds.
    2. Drill approximately halfway through the bolt, bring the drill bit out, re-oil it, and continue drilling.
    3. Do not let the drill bit sit inside the screw without moving it.
  4. Tap the hole with an 8-32 tap. (ELABORATE) 
    1. Turn OFF the lathe.
    2. Replace the drill bit with a center. 
    3. Tap through the bolt with good form. 

      3      5.  After removing the bolt from the chuck, secure it in a pair of pliers.
      4      6. Use a grinder (or a drill press with appropriate mounting) to de-burr the end of the screws, which may have sharp pieces poking out of them.

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