Sharpening a Large Drill Bit

Discussion in 'Shop Talk' started by Ken Scharabok, Dec 24, 2006.

  1. Ken Scharabok

    Ken Scharabok In Remembrance

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    Last summer I loaned my 1 1/4" drill bit to a friend. When they brought it back he said they had dulled it and he resharpened it. Well, it don't cut for swat since. Not something I want to do myself.

    Anyone here work in a plant with a tool room which routinely reshapens large drill bits? Someone on the order of the sharpening guy doing one for you on a favor basis?

    I'll pay two-way shipping.
     
  2. ace admirer

    ace admirer Well-Known Member Supporter

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    i usually just sharpen them on a belt grinder or large pedistal grinder freehand. its not hard once someone shows you how. (short people generally grind drills better than tall people, who can tell me why?)
     

  3. Beeman

    Beeman Well-Known Member

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    Would tall people grind bits better if the grinder were higher?
     
  4. ace admirer

    ace admirer Well-Known Member Supporter

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    why yes, yes they would, and short people would grind drills that broke very easy if they grind on a tall grinder. its all in the clearance angle, tall people tend to grind negative clearance angles until taught to look out for it. short people will grind a more close to proper positive clearance angles naturally.
     
  5. moopups

    moopups In Remembrance

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    In the clearance angle terms via a machine shop it is called 'relief angle', such can be explored via books from Lindsey Publications, (see this at links library), no association myself, just adequate info via purchases.