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- Secure the bolt in the chuck (preferably a collet chuck for a 1/4-20 screw) of a lathe (head end pointing outward).
- Using a center drill, create an indentation in the cap.
- Using a #38 #29 drill size, slowly drill through the bolt. Use coolant or oil to prevent overheating of the drill bit or part.
- Used a speed of 400 RPM and a feed of about 0.001" per 1-2 seconds.
- Drill approximately halfway through the bolt, bring the drill bit out, re-oil it, and continue drilling.
- Do not let the drill bit sit inside the screw without moving it.
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