Sharpening Twist Drills

[Rob Sack]

I did a search here and it redirected me to a few sites. Any suggestions on a sharpener for twist drills? I have a great sharpening service that does a terrific job on blades, brad points, and router bits. But they claim having them sharpen my smaller twist drills is not cost effective because I could replace them for the cost of sharpening. That seems like such a waste to just toss them when they need sharpe0ning. Other than Bob Vila's recommendation for the Drill Doctor, any other recommendations? I've tried doing them by hand on a grinder, but they usually don't come out much better.

[Frederick Skelly]

You can certainly grind them by hand.
I have the Drill Doctor and like it.
Fred

[Edward Weber]

I have one of the early models of the drill doctor and for standard twit bits it does a great job.

[Bruce Page]

How small are you talking about? Hand sharpening is my preferred method but the drill doctor my wife bought me does work well.

[Doug Colombo]

+2 for drill doctor. Works well for me.

[Mitch schiffer]

I have always done it free hand on a bench grinder. It only take maybe 30 seconds to do once you get the feel for it.

[Dan Friedrichs]

I thought the drill doctor was a cheap-feeling toy. Basically a dremel wheel on a little motor with a jig for setting angles correctly. Not at all what I expected for the price.

Something like the drill doctor is also going to wear out/fail at some point and get thrown away. So it's not like you're avoiding waste, unless you somehow would have gone through thousands of drill bits in its lifetime.

I just buy new bits. For a few bucks a piece, it's hard to even justify the time that it would take to sharpen.

[Bill Dufour]

Black diamond, darex
Bill D

[David Buchhauser]

I thought the drill doctor was a cheap-feeling toy. Basically a dremel wheel on a little motor with a jig for setting angles correctly. Not at all what I expected for the price.

Something like the drill doctor is also going to wear out/fail at some point and get thrown away. So it's not like you're avoiding waste, unless you somehow would have gone through thousands of drill bits in its lifetime.

I just buy new bits. For a few bucks a piece, it's hard to even justify the time that it would take to sharpen.

Depending on the size and quality of the drill bits you are using, it may well be worth while to resharpen. I use Precision Twist Drill Cobalt Jobber Length and replacement bits (1/2" diameter) are around $28 each plus tax/shipping. So for me hand sharpening is a no brainer. I own two of the Drill Doctors and find they do OK on the smaller sizes, but not so well on anything larger than around 3/8". I find it much more efficient to hand sharpen using a bench grinder with appropriate wheels.

By the way, I am using these bits for drilling steel, aluminum, etc. and very seldom are they used for wood.

David

[Maurice Mcmurry]

A little brass drill gauge is helpful. I have lost mine. I try to keep the OptiVisor within reach of the grinder. In 9th grade FFA Ag Shop we had to learn to grind a twist drill before we were allowed to use the drill press. My shop teacher has long since retired. He is still very active in the community. He gets lots of hand shakes and attempted hugs from his former students.

478070

[Alan Lightstone]

Black diamond, darex
Bill D

$4000 !!!!!! :eek:

Can certainly buy a few new drill bits for that amount.

[Tom M King]

A Darex came with a bunch of machinist tools that I was left by a dear friend. Even with that, I don't bother with bits less than a 1/4", even though I think all the collets are there. It does leave any that I do sharpen with it as good as they came to start with.

[Warren Lake]

free hand on the grinder wheel used for Chisels. Dull tools are useless and even if hand done its 80 percent as good as new its better than a dull bit. If its critical exact tolerance then a fresh bit is better as it will be more symmetrical than free hand.

[Andrew Seemann]

I do it freehand on my old Craftsman 6" grinder (handy skill from my machinist days), but my dad had a Drill Doctor that he used and it seemed to work well enough. Read the directions well though, he did a batch that somehow ended up with left handed angles on standard right hand twist bits.

Note that if you do get the hang of doing it freehand, you likely won't go back to a jig. I inherited the Drill Doctor 5 years ago and still haven't taken it out of the case. I keep thinking I will do a sharping of all my random loose bits, but I keep not getting around to doing it.

[Ron Selzer]

bought into the hype and bought a drill Doctor 750? years back complete with setup for left handed bits
ruined every bit that has been tried in it, needs thrown in the trash. spent too much money to do that
it sits on the shelf to remind me not to make that mistake again

[Dave Sabo]

This guy tested a lot of them and concluded the drill doctor was best despite the high price , but also thought an inexpensive jig you used on your bench grinder was pretty good even with the steep learning curve.

My big takeaway was that NONE of them were able to sharpen bit to as good a level as his best factory bits ��

https://youtu.be/pmr34sUFpK4

[Tom Bussey]

The sharpener is correct about sharpening cost verses buying new. I know for a fact that it cost more to re-sharpen a 1/2 inch high speed end mill that it costs to buy a new one. I talked to a guy at work Friday and he showed me a part it took him 23 seconds to make so as long as there was a bar to make parts from they took 23 seconds or every 23 seconds a part came out. I work in the tool room and and I estimate that it would take me about 15 minutes to make the part manually. Manual is not cost effective.

So cost for new drill bit verses cost to re-sharpen manually is the deciding factor. What he is saying is that if his cost to re-sharpen is 3 dollars and if the drill bit costs 1 dollar new then it is a no brainer.

I was also an instructor in the tool and die program at the local community college and I saw a student take a brand new 9/16 drill bit and he ground it down so it was of no farther use. Part of the program was to learn how to sharpen a drill bit by hand. He never passed that portion. so not all hands are equal. In other not everyone can sharpen a twist drill by hand.

At 76 I can sharpen anything 3/8th or over by hand and either at work or in my shop I have a bench grinder no more than 10 feet away. I have to pay close attention down to a 1/4 inch, smaller than that I can no longer see the wheel or feel the drill bit hit the grinding wheel.

In my shop at home I use a drill doctor to re-sharpen drills under 1 /2 inch. The drill doctor was a gift and to me well worth every penny. Big drills sharpened by machine need sharpening less often that than hand sharpening and when it comes to small drills , dull drills also brake more readily than sharp drill bits. Now at home, I have no sharpening cost involved, only time verses out of pocket cost for a new drill bit, not to mention travel costs to the hardware store to get a new one. So if on a fixed income, re-sharpening is the less expensive option.

The big problem is people do not actually read instructions and they over tighten the collet and if that is done then the drill bit will not cut period and then it is a waist of time to use it.

[Frederick Skelly]

bought into the hype and bought a drill Doctor 750? years back complete with setup for left handed bits
ruined every bit that has been tried in it, needs thrown in the trash. spent too much money to do that
it sits on the shelf to remind me not to make that mistake again

Well that's really a bummer, isn't it? I'm sorry to hear it. There must be some difference between the 500X I have and the 750 model. As long as I follow the directions, the 500 works very well for me.

[Rob Sack]

As a follow up to my initial post, Amazon just delivered the Drill Doctor 750. It works perfectly. Although it wasn't cheap and it would have taken the purchase of a lot of new bits to break even, the fact is it's fast, does a good job, and for me, the idea of just throwing away a dull bit and buying new seems too wasteful when that bit is perfectly serviceable.

[John Lanciani]

bought into the hype and bought a drill Doctor 750? years back complete with setup for left handed bits
ruined every bit that has been tried in it, needs thrown in the trash. spent too much money to do that
it sits on the shelf to remind me not to make that mistake again

I've been using a DD 750 since not long after they came out; every single time it has produced unsatisfactory results has been traced back to operator error...

[Derek Cohen]

I've been using a Drill Doctor 500X for about 10 years. Replaced a (worn) diamond wheel once. It does need to be used correctly. I've had sterling service from it all this years. I'd purchase another if needed.

Regards from Perth

Derek

[George Yetka]

I have a drill doctor its probably 20 years old or more and has never been opened. I gotta do some more drilling I guess

[Gary Thinglum]

I purchased the DD 250 when they first came out years ago. I'm sure have paid for it several times. I must have sharpened a couple of hundred bits without replacing the stone. It is slow but, does the job. The stone needs replacing but, instead of putting on a new stone, I would like to upgrade. Does anyone have any experience with the DD750X, or another one? Reviews I seen look good. Any comments?

[Derek Cohen]

Gary, as far as I am aware, the only difference between the 500X and the 750X is that the latter goes up to a 3/4" bit, while the 500X goes up to a 1/2" bit. I never use a larger twist bit than 1/2" so the 500X was the one I purchased.

Regards from Perth

Derek

[Dave Sabo]

I purchased the DD 250 when they first came out years ago. I'm sure have paid for it several times. I must have sharpened a couple of hundred bits without replacing the stone. It is slow but, does the job. The stone needs replacing but, instead of putting on a new stone, I would like to upgrade. Does anyone have any experience with the DD750X, or another one? Reviews I seen look good. Any comments?


What would you like to know ?

I can't see the $110+ upgrade cost over a new diamond wheel being a good value. The main upgrade is the ability to do a wider range of point angles and split points on the 750. Guessing you haven't missed those features ?

[glenn bradley]

Grandpa taught me to sharpen them at the wheel grinder but for nearly 20 years I have been using a Drill Doctor with good success. Quick, pretty fool proof, and about $100 today.

[Bill Dufour]

The general hardware jig works okay for larger then 1/4" or so. I often see them at yard sales. $23 at amazon or Hoe depot
Bill D

https://www.amazon.com/General-Tools-825-Grinding-Attachment/dp/B0002YOQ8Q/ref=asc_df_B0002YOQ8Q/?tag=hyprod-20&linkCode=df0&hvadid=198070022856&hvpos=&hvnetw=g&hvrand=11772220686686001930&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9032276&hvtargid=pla-383238090210&psc=1

[Gary Thinglum]

I have many old cement bits 1/8" to 1/2" which need to be sharpened. Has anyone used the 250 to sharpen them? As far as split point, I have very few.
With the need to replace the grinding wheel on my 250, I think it is time to upgrade to a newer version of the Drill Doctor, or another sharpener.
I agree with Dave the $110 upgrade over a new diamond wheel is a good value.
Thanks guys, for your imput.

[Bill Dufour]

I wonder if a regular drill sharpener can sharpen a cement bit or not? They normally have a lot of negative rake. Something wood or metal cutting bits do not use.
Bill D

[Warren Lake]

I sharpen by hand, have a general for over 40 years and still not tried it. I dont want to rush into things.

Have done concrete bits past and they work great other than I make them too sharp. You just need a green wheel. Freshly sharpened they were night and day just like high speed steel ones.

for high speed steel if its super critical that is that you cant be a few thou over you wont want to hand sharpen.

I was at a customers and went out to the car and my passenger window was smashed out, console rifled and broken. Did 10 other cars same time nice sunny afternoon. Auto glass place found a window for a 92 which was good and while there door apart and very experienced guy was drilling my door he was getting no where. He had to take an important call in the office and I asked if I could sharpen the drill bit. He said yes, he was a while so I took any bit I found and did a gaggle of them. When he started working again it was pretty much me being offered a job there.

Dull tools are crap. sharpening a drill bit is simple if not perfect is needed. Having a gizmo is fine and good for a shop, on site you will be a victim. 80 percent or more freehand is way better than a dull bit.

[Dave Cav]

I have a Drill Doctor that I got probably 20 years ago and haven't used for at least ten. Generally I can touch up anything over about 1/4" on a bench grinder or belt sander, but it does take practice. I generally just buy new bits in quantity to keep on hand, up to 1/2".

[Steve Rozmiarek]

I have many old cement bits 1/8" to 1/2" which need to be sharpened. Has anyone used the 250 to sharpen them? As far as split point, I have very few.
With the need to replace the grinding wheel on my 250, I think it is time to upgrade to a newer version of the Drill Doctor, or another sharpener.
I agree with Dave the $110 upgrade over a new diamond wheel is a good value.
Thanks guys, for your imput.

Masonary bits aren't supposed to be sharp, they are in essence little jackhammers with an auger attached to clear dust. Once the hardened edge wears off, toss them.

[Warren Lake]

faced with a dull 1/2' that had slowly dulled I tried the green wheel. When you are working and need to get stuff done going to get another bit or ordering one is useless.The sharpened bit worked great, If I remember correctly it also drilled through some 2 x 6 that it would not have done even if a new one, then into the concrete from there. Likely using lag bolts or those expansion inserts at the time.