Drill Doctor

This was discussed to death awhile back.

I have a Drill Dr 750 and also sharpen by hand.

My thoughts are that the drill Dr. (750) works just fine if you take the time to learn how to use it properly. Using it wrong can produce less than good results. Particularly if you don't keep "grinding" until the Drill Dr. stops cutting metal. If you stop before then you are likely to get uneven and improperly ground flutes.

As everyone is aware sharpening by hand can produce excellent results. But then again, you need to learn the proper technique and have the "feel". Getting the "feel" requires practice.

Neither one is foolproof nor can either one sharpen a drill for a damn without training, practice and attention to the procedures.
 
This was discussed to death awhile back.

I have a Drill Dr 750 and also sharpen by hand.

My thoughts are that the drill Dr. (750) works just fine if you take the time to learn how to use it properly. Using it wrong can produce less than good results. Particularly if you don't keep "grinding" until the Drill Dr. stops cutting metal. If you stop before then you are likely to get uneven and improperly ground flutes.

As everyone is aware sharpening by hand can produce excellent results. But then again, you need to learn the proper technique and have the "feel". Getting the "feel" requires practice.

Neither one is foolproof nor can either one sharpen a drill for a damn without training, practice and attention to the procedures.

Thats too bad,
I been using one for years with better than factory results. I also use the split point feature that works well as the final step.
My DD came with a instructional VHS video so that should give you guys an idea how old this thing is. I had to replace the diamond wheel twice over the years. These wheels can be flipped one before requiring replacement. I don't know anything about the current models but the old classic "tombstone" model works great. I learned to sharpen by hand back in HS machine shop and still sharpen the larger 3/4"+ manually.
The two most important tips I can provide is:
1) Setup the drill bit correctly from the start with the spring tangs even in the flutes then snug up the collet without rotating the bit.
2) always grind in even numbers with a consistent hand feed gliding through the lobes. Look,listen and feel.

Dont discard your DD guys, they really do work, it's NOT a gimmick.
Paco
 
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I sharpen by hand. Sometimes I use my Darex to do the 135° split point. I tried the DD once. Cheap construction and iffy results. My 3 cents…Dave.
 
What about the Chisel and Relief Angles I see you can adjust?
 
I done thousands of bits on mine, have actually wore out 2 units, now on my third 750X, they have paid for themselves many time over.
 
I don't own one but when it first came out some old timer tuned me off them saying it was a gimmick, now with all the praises I hear, I'm thinking maybe I should get one an find out for myself.
 
2) always grind in even numbers with a consistent hand feed gliding through the lobes. Look,listen and feel.

Dont discard your DD guys, they really do work, it's NOT a gimmick.
Paco
I agree, they work good (especially when your eve sight isn't so good). I almost never sharpen drills by hand anymore.

Grinding with consistent turns will not work so good if the drill bit has inconsistent flutes to begin with. That is why I set my depth of cut to be minimal (the bolt head where the tangs get alligned) and grind until the DD does not remove any more metal. That way I am assured that the complete flute is ground and that both flutes are ground evenly. I've had instances where I counted turns, quit before the DD ran out of metal and had a poor functioning drill bit.
 
The two most important tips I can provide is:
1) Setup the drill bit correctly from the start with the spring tangs even in the flutes then snug up the collet without rotating the bit.
2) always grind in even numbers with a consistent hand feed gliding through the lobes. Look,listen and feel.

Dont discard your DD guys, they really do work, it's NOT a gimmick.
Paco

Agree with the tips. The spring tangs do not always hold the bits as firm as desired, so need to tighten the collet carefully and watch for any rotation. If the tangs even slightly open a little more, need to reset.
 
The 750x works good on drill bits up to 3/4" as advertised. I find it easier and quicker than a bench grinder free hand. A quick touch up is painless and quick if you follow the directions. I read the directions twice and in 5 minutes I was sharpening bits and was pleasantly surprised at the even consistent points. The split point feature works okay on the smaller bits, its not ideally placed on the larger bits, its well behind the cutting edges on my 3/4".

The 750x has more adjustments than the older models and its worth the added cost over the 500 to me. I find the key to using it is to grind till it stops taking metal, keep count of the turns and repeat on the other side. Ease into the depth adjustment till it takes just enough metal off. Mine came set too aggressively, got it adjusted where it takes off about 1/16". Works good, quick touch ups are consistent. Adjust it up to fix rough bits, back off for touch ups. I paid $125 shipped off eBay, its saving me time and money since most of my bits are cobalt and pricey. I keep them in better shape now, its quicker than the bench grinder for me so, my bits are kept in tip top condition now. Still use the bench grinder for large bits of course.
 
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