Why can't you manually re-sharpen a center drill?

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Top comments include:

• “I’d rather ask why we are using a center drill in a modern machine shop?”
• “Its a center drill, meaning it has a precision cut center point. If a drill is not perfectly sharpened right then your .500 hole is now .521 or it could be undersized by .0.025 for a hole size of.475 hope you see why. Enjoy and good luck.”
• “You can , but if the point gets too short, you may have to redrill the point depth or the live centre could touch the bottom of the hole , and the part would not run true”
• “Re sharpening center drills is fine for manual work but if you use a re sharpened drill in CNC and use the formula to calculate the center drill depth, you most likely won’t have the correct size chamfer around your center drilled hole. You’ll have to adjust your depth accordingly.”
• “I do it a lot. Just the tip. On bigger work you don’t have the RPMs so they dull and load up faster.”
• “Take one with a broke tip and grind a slot in the middle to use like finger cutters to get another broke tip out of a shaft”

• “You can sharpen anything if you have a crack haha we used to reduce the radiuses on particular inserts on disk face cutters to stop chatter..

  one thing I was told as an apprentice, learn to sharpen HSS and you’ll always have a job.. and it’s bloody true.”