Drill Sharpening machines

[Rough Edge racing]

  You guys can be sharp.............. ......I have what seems like  literally 1000 drill bits...they are all dull, some are duller that others...I do fabrication on bikes  all the time so sharp drill bits are nice. I do sharpen drills by hand on the grinder but it's not the best....I see home owner drill sharpening machines for less than $100. Do they actually do a decent job and have a long life...?  The drills are ground on center and eat through the metal?  The machine grinding wheel wear out quickly? Or is it better to buy a jig that clamps to the rest on a bench grinder? Thanks....

[Perazzimx14]

Years ago a co-workers wife bought him a Drill Doctor. He brought it to work to put it through its paces. Since the bit is not cooled when the stone is against it, it seemed to loose some temper from over heating. This was 1/16th thru 3/8" bits. While it did work it turned into drill a hole in 1/4" mild steel re-sharpen the bit repeat.


It is better than me trying to sharpen a bit by hand where its attempt to sharpen, eff up the angle throw out the bit and get a new one.

[twowings]

I have had a Drill Doctor for a few years now...as has been said, the bits never seem to work as well as before sharpening...I just bite the bullet and wait for sales and pick up a new set and keep the old ones that have some life left...it may be that I don't know what I'm doing...my wife will verify that....

[Lumpy Idle]

i have a drill doctor 750 and i got it because i thought it would be easier than trying to touch up the drills on the grinding wheel. i never became competent at freehand sharpening of the bits on a grinding wheel. i could use a lesson or two from a competent machinist, especially for those bits under 1/4"

so, i was enthusiastic about the drill dr.  welllllll... long story short... (in general - and of courseYMMV) it is better on larger bits than on smaller ones. the replacement diamond wheels are expensive and i don't think they last long enough to justify the frequency of their replacement.

in the intervening years since i purchased the drill dr. i have gotten a bit lazier and that is perhaps a consequence of finding out that the drill dr. wasn't the solution to my problem. i have taken to buying large cheap chinese drill bit sets when they appear (rarely these days) at costco. i use these bits for wood working and for aluminum. for steel i still use the decent black oxide bits and i have a small set of cobalt bits. when the bits used for steel get dull i try to give them a hand sharpen and when that fails they go into a plastic tub ....and i think about buying the next set of decent bits.

this is clearly not a good system but i have to say that the drill doctor is not a step toward the answer - at least for me.

[Chuck in Indiana]

Ok. I learned to sharpen drills by hand when I was an apprentice. I used to use a Darex drill sharpener when I worked for GM. ($$) That sucker was *nice.*
When I saw the drill doctor, I bought one. I can do better by hand..  except for carbide. The diamond wheel will sharpen them. It's Mickey Mouse, though.

[Huzo]

Or just learn to do it properly.
I do notice these days though, that 3/16 th’s or smaller, and I have trouble seeing well enough..

[delrod]

I have had the same luck with the drill doctor class of sharpener. However I have recently acquired a 3000 dollar class purpose built drill sharpener. When and if I can afford to pay for the missing bits and pieces I will let everyone know. Will certainly be interested in sharpening drill bits for motorcycle gas money

[blackcat]

About 15-20 years ago I bought a Black and Decker drill sharpener and it did a decent job....sometimes.  Now I just toss the old ones/lose them and buy new.

[twowings]

It's one of those handy suggestion items when family asks "What do you want for Christmas/Birthday/Father's Day, Dad?"    :cool:e

[Chuck in Indiana]

Or just learn to do it properly.
I do notice these days though, that 3/16 th’s or smaller, and I have trouble seeing well enough..

Huzo.. I have over 50 years as a journeyman tool and die maker. I've ran my own shop for 33. I can run *any* tool room machine. Don't tell me that I don't have the expertise to run a Drill Doctor.  Like I said, it's Mickey mouse.

[dxhall]

The problem with cheapo bit sharpeners is that they don’t hold the grinding stone(s) on the same axis as the drill bit.  This causes the stones to create a point on the bit which is not on its true center, which causes the bit to drill an oversized hole.  If a Drill Doctor did a great job, there would be no need for sharpeners which cost ten times more money.  You need to see my Spiropoint in action ...

[cliffrod]

I like sharpening tools, which is good because I sharpen (mostly carbide) chisels endlessly in studio carving granite.  Same with my chefs knives, all variety of wood tools, chainsaws, etc, etc.  All is done freehand, no jigs or gimmicks.   The only challenge that I didn't overcome was sharpening small drill bits and keeping the point centered, especially now that my eyes are not as young as they used to be.... 

On <1/4" bits, they disappear fast chasing a centered point.  So I bought my drill Doctor about 20 years ago and use it all the time.  Still on the first diamond wheel.  I find better drilling results with the bits if I split the point after sharpening, which is also done on the drill Doctor.  I've bought & acquired a lot of "useless" dull bits for free since getting it, because I know most will sharpen without issues.  I would recommend a drill Doctor without reservations but they are not foolproof....

For people outside the trades, It's important to understand that industrial diamonds cannot tolerate heat extremes.  If you get them hot enough to spark and keep going (on metal or stone) they will fail and no longer cut anything.  at the same time, if you heat your bit until it holds color (blue, straw, whatever) you'll overheat  the tool steel bit and anneal it.  Double fail & 100% user error.  If it's tempered and you cannot hold it with bare hands, it's too hot.  So go slow and don't get either bit or diamonds hot and all is good.  Curiously, if you try to carve ice with diamond tools, that extreme cold also wrecks them. 

In some applications, water is used to help keep the diamonds cool so you can grind more aggressively.  A drill doctor isn't equipped for water cooling.   so if you thermal the diamond wheel during aggressive use and don't slow down the thin layer of diamonds on the wheel will be destroyed very quickly.   It's also not designed for heavy grinding, just for sharpening and minor stock removal.    For best results, shape a badly dulled or broken bit to approx shape in a regular grinder (freehand or otherwise). Appropriate effort when grinding against the drill Doctor wheel will help it last through hundreds if not thousands of sharpening.  I will check my depth and reset the holder during sharpening and that helps a lot to produce a great, sharp bit.  Then, just like any other sharpened tool, I keep it sharp instead of letting it get dangerously dull.  A few seconds in the drill Doctor and all is good.

Splitting points is also best done as a check & reset depth as needed.  Going slow and sneaking up on the split is better for the tool than one step with hard pressure.

As mentioned, ymmv.  Just like some here have stated, Some professional machinist friends have told me it's a Mickey Mouse gimmick.  Everyone has their own opinion.  Keeping a green or carborundum wheel perfectly dressed just to sharpen bits is one more obstacle and expense in the shop.   the diamond wheel in the drill Doctor is not stone. It is metal with surface bonded diamonds, which maintains its shape as long as the diamonds are intact.  Having a stone in there would mean constant dressing to maintain profiles.

Used properly, a drill Doctor works great for me- especially on the little bits.  I would not pass a professional drill bit sharpener if the opportunity arose for low$$.  Until then, I'm very happy with mine. 

[Rough Edge racing]

  Hmmm...I can buy an acceptable 6 inch variable speed grinder for around 100 bucks or so...A drill guide is about $50...I wonder if this better ??? I can get my wife to do it...She has great sewing/knitting skills, like 20 fingers on each hand..

[Lumpy Idle]

just for the danged heck of it i went over to the darex site to look at their machines. the top end offering is $33k (not a typo.) i love their sense of humor. they have a purchase cart with a spinner for the number of machines you want to buy. yeah. uh huh.

[Ncdan]

I have found over the years that if I tried to save money and buy cheap bits regardless of how you sharpen them you still have a
cheezy drill bit. Spend the money for good quality America made bits and you don't need to worry about sharpening them often if ever, if one uses them occasionally.

[Murray]

This is the only one I've ever used that actually worked https://www.machineryhouse.com.au/D111 nb prices are south pacific peso's, the couple of the the home style ones I've used a half arsed free hand guess on the grinder is more effective, years ago the old man had a rest for the grinder that allowed you set up the angles etc it wasn't quick but might be a happy medium.

[Muzz]

If your stone is an aluminium oxide (white) as distinct from a carbide one, your bits will not burn anywhere near as badly. Highly recommended.  Way better for grinding chisels and plane blades.  Take it gently and you don't need water.

I can do a reasonable job by hand, but below 6mm is a bit random.   An 8" grinder is far easier to use than a 6".

I have a basic wooden guide set up so that I get a reasonably accurate angle.  The included angles are usually something like 118deg for soft stuff such as wood, and I think about 135deg for steel.  I just use this angle now as most of my pottering these days is in steel.

Important that there is relief at the back.  I bought a set of cheap HSS bits once (mainly for the container ) and they had reverse relief!  I bet a fair few people were cursing when they found they didn't work!  Funnily enough, the drills themselves weren't too bad once the relief was corrected.

[Chuck in Indiana]

and they had reverse relief!

Yeah, I've seen that, too..

[Huzo]

If you machine reverse relief by hand, is that called “hand relief..”

[Ncdan]

If you machine reverse relief by hand, is that called “hand relief..”

Lol, buddy, have you been in that fermented  cactus juice again😂

[Huzo]

Lol, buddy, have you been in that fermented  cactus juice again😂

No mate..
Maybe that’s gonna’ be my excuse..

[73eldorado]

I have had a drill doctor for. 20 plus years, never changed the stone or had any problems. I have sharpened some of my bits so many times they are half the length of new ones, never turned a drill bit blue. There is no way I would let this tool out of my shop as it has saved me many dollars and the bits are as sharp as new when done. I recommend it to anyone interested in a quality unit. I work out of my shop at home for a living so it sees a lot of use, zero problems.

[Knuckle Dragger]

Huzo.. I have over 50 years as a journeyman tool and die maker. I've ran my own shop for 33. I can run *any* tool room machine. Don't tell me that I don't have the expertise to run a Drill Doctor.  Like I said, it's Mickey mouse.

I don't think he actually was....  not the way I read it anyway.

I personally can't sharpen bit for nuts.  I sometimes have a go.  On a horizontally running angle grinder.  I have good days & bad days, sometimes mixed, too, but mostly bad.  My father (god rest 'im) gave me an English Martek?? sharpener with a couple of stones but without motor.  Sort of an ultra-cheap bottom-'O-the-range DD, only worse.  Worse even than my own meagre, abortive freehand efforts.  I wouldnt've thunk it possible but it was, is & probably always will be.

I seem to use lots of the same sized drills.  Esp. 1/8, 1/4 & 3/8.  Still in the dark ages with non metric drill sizing in my household.  Probably 100 x 1/8" to any other intermediate sizes & 10:1 to the other frequent user sizes.  Even a 750X, despite its relative 'sophistication' to the POS English one, is useless on 1/8" sizes.  In fact, my limited efforts on a borrowed DD750X were pretty well useless too.  My efforts, mind.  I'm not saying the DD is crap:  I might've just been using it incorrectly. 

Luckily, OZ still thankfully has local world-class indigenous drill manufacture.  They're also remarkably cheap when bought in 10s, and cheaper yet in greater quantities.  I haven't bought a driil set in about 20 or even maybe 30 years, as most individual drills remain all but untouched.  Just the appropriate Imperial sized drills for Metric M2-M12 taps & pilot holes.  I also buy individual Cobalt drill sizes for stainless & cast as required. A set of quality Sutton Cobalt drills for me would be a mostly unused, wasteful extravagance!

Life's way too precious for me to piss around sharpening tiny bits that I can't see the included angles of any more.  I can always use the excuse that I'm helping to keep Sutton/Patience & Nicholas/Evacut/Osbo(u)rne Industries afloat & employing fellow 'Strayanz & Enn Zudders.

I've found Chinese drills to be complete & utter crap.  Won't use them on principle.  Even the P&N imports are crap too.  The only imports that I've used & liked have been EU sourced Dormers & Fisch bits from Austria or Germany (unsure exactly where).

[s1120]

I've found Chinese drills to be complete & utter crap.  Won't use them on principle.  Even the P&N imports are crap too.  The only imports that I've used & liked have been EU sourced Dormers & Fisch bits from Austria or Germany (unsure exactly where).

OK, so ill start by saying this was a few years ago...  but going back 5-10 years ago, I had real good luck with the Chinese drill bit...  well kinda...  Strange to say the steel used was pretty good. better then some of the US made bit I was buying. problem was the angles were out to lunch. So with the common workhorse sizes I would just get the cheap bits, and sharpen them. Granted like a lot of you all here age has taken some vision, and I really cant see what im doing. I also have a dril Dr.. I havent used it in a few years, but I used to use it a lot to touch up edges. Ive really gotten into just getting new bits now though...  I just dont fab much any more like I used to.

[Huzo]

Huzo.. I have over 50 years as a journeyman tool and die maker. I've ran my own shop for 33. I can run *any* tool room machine. Don't tell me that I don't have the expertise to run a Drill Doctor.  Like I said, it's Mickey mouse.

Chuck...
It’s a little thing called self depricating humour, no need to sell your credentials to me.
But if you’re going to draw your sword, please make it nice and sharp for a clean cut, perhaps with a little reverse relief..?
PS
With a name like Chuck, I expect you’d sure as hell know your way around a lathe...

[Ncdan]

There was a video going around a couple years ago "how to sharpen a drill bit"
In the video it showed to weld two 1" nuts together, and using the angle where the two flat sides of the nuts are joined is suppose to be the perfect drill point angle. Can any of you  machinist verify this? If so it woukd be easy to sharpen any drill bit if one can verify the angle by using the nuts for a guide.

[Rick in WNY]

Dan, two hex nuts tacked together flat to flat would give a 120 degree angle.

The commonly ground end angle on commercial drill bits is 118 degrees, so 120 is generally "close enough"

That said, this guy made a great vid about drills and sharpening. It is the "long way around" but it's worth watching as he explains everything in terms the average Joe can comprehend.

https://www.youtube.com/watch?v=r8oORR6jyh8

[Chuck in Indiana]

Chuck...
It’s a little thing called self depricating humour, no need to sell your credentials to me.
But if you’re going to draw your sword, please make it nice and sharp for a clean cut, perhaps with a little reverse relief..?
PS
With a name like Chuck, I expect you’d sure as hell know your way around a lathe...

Not drawing my sword to you, Huzo.. pointing it at the Drill Doctor. The *most* important thing about sharpening drills is to get the flutes on center. The DD has a couple of MM  spring steel jaws that can and will put the center off. The cheesy collets that hold the drill.. oh, never mind.

[mtiberio]

Dad was a tool maker, and I remember the time he pulled me aside and said, "the books say you can't do this." That is when he showed me how to hand sharpen a drill bit with a bench grinder. Never thought about getting a jig to do it.

[tris]

Or just learn to do it properly.
I do notice these days though, that 3/16 th’s or smaller, and I have trouble seeing well enough..

I was taught how to hand sharpen drills and chisels/knives

I'm not too bad at doing drills but hopeless at chisels

I bought a used Tormek machine to solve the chisel problem

I have the T4 which is fine for most people but the bigger T8 is probably better overall and they also do a fixture for drills

https://www.tormek.com/uk/en/

Practice makes you better but a proper machine makes you perfect!