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Old 11-29-2016, 09:54 AM
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Default choosing a bench grinder

Hello all, I need a little advice on how to choose a bench grinder. usually in the past whenever I had a dull drill bit, I would just toss it into my collection of dull drill bits and buy a new one. now that I've accumulated quite a collection, I've decided to see if I can sharpen them myself. should I purchase a slow bench grinder, or a variable speed? also, are the speeds different for sharpening different types of tools? Thanks
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Old 11-29-2016, 11:17 AM
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I would select a grinder with good quality bearings. I have noticed some spin on for minutes after shutdown and others come to a stop soon. 3600rpm and a fine grit aluminum oxide stone, and you should be good.
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Old 11-29-2016, 11:51 AM
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Quote:
Originally Posted by Ironman View Post
I would select a grinder with good quality bearings. I have noticed some spin on for minutes after shutdown and others come to a stop soon. 3600rpm and a fine grit aluminum oxide stone, and you should be good.
I disagree with the fine stone, I would use a medium grit because a fine stone will grind slower and tends to over heat and burn a drill bit. IMO
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Old 11-29-2016, 01:20 PM
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There are two schools of thought. First there are people who hand grind their drills. I was like you and had a bunch of dull drills. I watched videos bought jigs etc to solve the problem. I was able to get occasional good results hand grinding. That wasn't good enough so I spent a couple of hours grinding and re-grinding and I eventually got good results. The problem was when I went to grind some a year later, I had forgotten how to do them perfectly.

I bought a Drill Doctor and all my drills are BETTER than factory in terms of sharpness. I had my dull drill and my BIL gave me a bunch to be sharpened. I had my 2or 3(?) magnifying light out to really have a good look. Some of my BIL's drill in the set he gave me had never been used and I looked at them vs what the Drill Doctor was producing. DD was consistently better.

In addition, I split pointed the drills. You cannot do that hand grinding. Hand grinding is a great skill but unless you are doing it all the time you never get great doing it. IMHO there are other more useful skills to learn.
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Old 11-29-2016, 01:24 PM
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I would select a grinder that has the word "Baldor" written on it somewhere.

Sitting on the bench next to my Baldor grinder is a 30 + year old Harbor Freight grinder that is excellent and refuses to die. 3/4 HP is about as low power as I would go. A good bench grinder should last a lifetime.
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Old 11-29-2016, 03:14 PM
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Five year guareentee, low speed 1/2 hp grinder set up for sharpening. You may find it cheaper some where else.


http://www.woodcraft.com/product/158...d-grinder.aspx
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Old 11-29-2016, 05:06 PM
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If money is no object get a Baldor. If your budget does not allow, I have had excellent luck with an 8" Jet, so much so I will buy another as a dedicated deburring machine. Only thing with the Jet is to throw the stones away immediately and put on some decent ones.
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Old 11-29-2016, 06:14 PM
Lew Hartswick Lew Hartswick is offline
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Quote:
Originally Posted by rmack898 View Post
I would select a grinder that has the word "Baldor" written on it somewhere.

Sitting on the bench next to my Baldor grinder is a 30 + year old Harbor Freight grinder that is excellent and refuses to die. 3/4 HP is about as low power as I would go. A good bench grinder should last a lifetime.
I tend to agree with the sentiment. :-) We have two of them at school. In addition if possible a 60 grit on one end and 100 on the other, the pink AlO2, is what we use for lathe bits etc. IF the only thing you're talking about is drill bits then the Drill Doctor is going to do you a LOT more good and a LOT easier to do right. :-)
...lew...
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Old 11-29-2016, 10:34 PM
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In addition to a Baldor grinder another brand would be Rockwell, they were a smooth running machine.
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Old 11-29-2016, 10:47 PM
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If you are just looking to sharpening drills I'd recommend getting a Drill Doctor. No skills to earn and you get sharp bits about 1 minute.
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