DIY Drill bit sharpening

JHZR2

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New Jersey
I assume that most folks just throw away drill bits when they get dull. I dont have a grinding wheel, and probably dont use bits enough to justify the investment. Is there another DIY way to do this? Is there someplace that I can send them to for a nominal fee? Thanks!
 

JHZR2

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Problem is that I dont have a bench grinder or access to one. And for the number of bits that I use/go through, its probably not worth it for me to buy one... I do have a dremel...
 
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Bad Axe, MI
Originally Posted By: JHZR2
Problem is that I dont have a bench grinder or access to one. And for the number of bits that I use/go through, its probably not worth it for me to buy one... I do have a dremel...
Yea that would make it tough,for you i guess just buy new when dull since you don't use them often. But bigger bits can get pricy too..
 
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california
I use my 10 dollar HF angle grinder and either a grinding wheel, or a cut off wheel. It is not always easy to get the tip centered, and the bit will walk a little on a new surface, but I can get them super sharp. I've gone head to head with a drill doctor, and My hand sharpened bits were making long steel pig tails where the drill doctored bits were making flakes at a slower rate.
 

Kestas

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For all the restoration you do, I would expect a bench grinder in your garage. Mine has a grinding stone on one side and a wire wheel on the other. The wire wheel comes in handy to remove corrosion and gunk on threaded fasteners and brake hardware. Make sure you get the fine wire wheel.
 
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ME
I have a drill doctor; got it for xmas. Don't really care for it. I mostly go through 1/8" bits so I just found a cheap source of them by ten-pack.
 
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Central Coast, Calif.
Bits under 1/4" are difficult to sharpen by hand. You should also own a drill guage so you sharpen them evenly at the correct angle. If they are sharpened with the center off to one side it'll make the hole oversized. I own a basic model drill doctor and like it quite a bit. It'll go down to 1/8" with no problems These videos are the best I've seen for sharpening and use of drill bits.
 

JHZR2

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FYI, drilling into metal, which is supposedly what the riffle cryogenic bits are for, got me this:
 
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Kansas
I prefer the cobalt drill bits. We have sets of them at work, and if I need one at home, I can borrow one. But, for home use, they're a little too expensive. I usually stick with the cheaper HSS bits for home use.
 
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JHZR2

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Originally Posted By: tom slick
Your pilot hole was too big, that's why the shoulders are chipped. I'd have used a 1/8" pilot then the 3/8" bit.
That's exactly what I did! I did put a 3/16 hammer bit in after the 1/8, but it fit right in...
 

JHZR2

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Originally Posted By: Bamboooo
I prefer the cobalt drill bits. We have sets of them at work, and if I need one at home, I can borrow one. But, for home use, they're a little too expensive. I usually stick with the cheaper HSS bits for home use.
I bought the cobalt ones as they seem to be us made. Some of the holes I made with titanium bits or black oxide, which I felt cut better for longer.
 
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Central Coast, Calif.
Cobalt is great on hard/abrasive materials but more brittle so it may be more likely to snap when abused. i.e. drilling with a hand drill in metal. TiN ("Titanium") or black oxide is irrelevant outside of a production machine shop. These coatings provide a degree of lubrication on the flutes to extend the life and better chip extraction. The life of a uncoated good bit is well beyond anything a home shop is ever going to see. Buying a high quality bit is more important than the coating.
 
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ks, wichita
man o man, fantastic info. when i was young an old guy showed me how to sharpen a bit by hand. i thought it could not be done but i did get it done. with out a gauge.
 
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