So I have been using a bench grinder to sharpen my bits, which I think I have been doing real good with. But there is a 3/8 bit that I used for some metal and have a interesting profile but I reshaped the head to be like a normal twist bit. It cuts chips very well, but there is a wide point on the bit. On a normal' bit there is a nice point. The one I sharpened has a wide point, almost 1/16 or 1/8. Someplace in that range. I do not know what I did wrong. I kept the angle the same, at 120 or whatever. But what about The angle for the flute directly? I think I had it at 10' maybe more. Can't say because I do free hand. So what would be some details for sharpening a bit correctly so it has a good point, to keep from running on the wood.

  • I will be adding a picture later, just so people know. – Ljk2000 Mar 22 '17 at 14:07
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    "On a normal' bit there is a nice point." On a normal bit there actually isn't a point, at least not from the factory. The way twist bits are ground at the factory it can look like there is a point in profile (especially at smaller sizes) but in reality there's a small 'ridgeline' along the tip, see diagram here and photo here. – Graphus Mar 22 '17 at 16:42
  • @graphus So I may not be doing anything wrong? – Ljk2000 Mar 22 '17 at 16:48
  • You'll want to make sure that the sharp edge at the tip can still bite into the wood. If you aren't careful it's easy to make the back rise higher than the front. – ratchet freak Mar 22 '17 at 17:09
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    "have a interesting profile but I reshaped the head to be like a normal twist bit" - if this was something like a "bullet-point" bit that you have ground back to approximate a normal twist point the web may be excessively thick. This condition also arises when a normal twist bit has been ground down a lot, and grinding to thin the web at the point is needed. – Ecnerwal Mar 23 '17 at 13:31

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