Sunday, June 2, 2013

Drill Doctor

If you have ever wondered why a drill bit was taking forever to cut through steel or aluminum -- it is usually because the drill bit has been dulled by turning it at too high a speed or without sufficient lubrication.

I bought the Drill Doctor to solve this problem yesterday -- the more expensive model, because that is all Home Depot carries -- and I am glad that I did.  If you are wondering what a Drill Doctor is -- no, it isn't a guy with a German accent asking a drill bit on the couch, "Zo, how long have you felt like you are going around in circles?"  It is a gadget for sharpening drill bits. 

It isn't quite as simple as I had hoped or expected, but it is simple enough.  You put the dull drill bit into a chuck, press a button, put the chuck into an alignment guide, then put the assembly into another part where a diamond wheel sharpens it as you turn the chuck.  It is a very clever design, although it isn't foolproof.  If you don't do it exactly right, you don't get a sharp bit.  Most of the bits that I had that needed sharpening improved dramatically, sometimes on the second try.  It seems to work better on the larger bits -- but those are the ones that for me typically get dull, because I am usually drilling large holes in metal with them.

This should save me a bit of time on ScopeRoller manufacturing, as well as meaning that I won't have to run out and buy a new drill bit as often.


  1. I have had a DD Model 750 for at least 10 years now, and consider it an essential piece of shop equipment. You're right that a bit of care is required to get good results, but it isn't really difficult.

    A good machinist can sharpen a bit by hand/eye and it will do a perfectly satisfactory job. Unfortunately, us [mostly] self-taught machinists don't always fare so well. I can make a bit cut, but I'll guarantee the hole won't be on-size.

  2. Yeah, I have one of the smaller models that I bought back when I was doing BattleBots (2001-2) and sometimes I would sharpen a new drill bit because it came out of the machine better that it started. It's absolutely essential.

    One thing to look at is where the line at the tip of the bit is relative to the white markings on the bit holder.

    Now if I could figure out how to sharpen this 1" drill I've got....

  3. Mauser,
    Get one of these:

    Then, either find a book or YouTube video that shows how to sharpen a bit by hand. When he was a T&D apprentice, my cousin was taught how to sharpen drills and he gave me a real quick lesson. The most important takeaway was the motion required; you don't rotate the bit, you "roll" it up the face of the wheel.

    You'll want your grinder to have a flat face on the wheel, which will probably require dressing it.

  4. The Drill Doctor does sort of a rocking motion as you rotate it. I think they must make a version for larger drill bits.