Sharpening Drill Bits

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How do all of you sharpen drill bits?  I have used a drill doctor in a shop I worked at, but I was never that impressed.  Is there anything else out there?Thanks!
Reply:A bench grinder?-Heath
Reply:I use a bench grinder to sharpen all standard bits.  I haven't figured out how to sharpen split point bits yet.
Reply:Go buy yourself a Drill Doctor.  It will be the best money you have ever spent.Millermatic 175Miller Sychrowave 180sd
Reply:I have a book that provides some guidance.  This is actually pretty easy, once youve done it a couple of times.  If you are doing it by hand, the main things to keep in mind is the angle and the taper away from the cutting edge.  The cutting edge should touch the work surface before the trailing edge does, so you want to take more metal off the trailing surface than you do the cutting edge (that part is hard to explain, I'll try to draw a picture to explain better).  You will not be perfect without a jig or guide, but you  can get pretty close.  There is one more page with a bit more info that I goofed up and didnt get.  I will post the rest tomorrow.Just as a note, this was my highschool metals/welding text, published in the 50s and used up to the 80s.  Good info never goes out of date. Attached Imagesp1.pdf (75.0 KB, 319 views)p2.pdf (145.2 KB, 194 views)Last edited by smithboy; 03-02-2006 at 08:12 PM.Smithboy...if it ain't broke, you ain't tryin'.
Reply:I got to agree with the drill doctor suggestion. I am a tool maker by trade and it took me some time to properly resharpen a drill. The drill doctor takes all the guesswork out of it and does it really fast. It is money well spent. Just my $.02.
Reply:Oh, come on now!  He might'a been asking how to do it the hard way...Smithboy...if it ain't broke, you ain't tryin'.
Reply:i use a belt sanderdont matterfrom 1/16 to 5"cut like there going thru butter  ...zap!
Reply:I use a bench grinder to sharpen the edge, set the angle/taper, and relieve the area behind the edge, then I "thin the web" with the corner of the wheel. I think this is one of those things that you have to watch being performed in order to fully understand it.
Reply:You mentioned that you didn't like the Drill Doctor, I have to wonder why as I find it to be a low cost machine that actually works well.    We have one at work and it has saved my but several times doing maintenance work on stainless steel.    That in an environment where we often throw out bits when they get dull.    I find that at times the Drill doctor ends up putting a better edge on the bit than the factory.It does take a bit of getting use to of course.   Do spark out the bit, that is keep grinding with the bit in the chuck until there are no more sparks being produced.    A Drill Docotor is a good machine when used within its limits.   For things outside its limits you might want to consider professional sharpening, especially in the larger sizes.   Yeah that may seem like an expense but done well can bring a bit back to new condition with all the features in the proper position.As to manual sharpening I've done so on both a belt sander and a bench grinder.    Can't say that  I was ever good at it and probably am a lot worst now that the eyesite isn't 100%.    The motions are a bit difficult to describe but if you look at a new bit you will know where you want to go.    The biggest problem as far as I can see with manual grinding is that you never really end up with all the features in the right place.   There are gages to help with that though.Dave
Reply:I have a Drill Doctor 750 that I've had for a year.  Because I sharpen larger size bits than 1/2" I purchased the course wheel that goes inside.  I have sharpened 5/8" bits until they're half the size of a normal bit and they cut better than a new bit.  I actually cut one in half with a band saw to see how well the Drill Doctor worked when I first got it.  It put a better than new point on the bit.  To re-sharpen a 5/8" bit takes me about 2.5 minutes from dull.  I had problems when I first started using the Drill Doctor and nothing would sharpen for me.  I found that it was the position of me in relation to the Drill Doctor.  I lowered the Drill Doctor down from the height that I had it sitting at and everything started sharpening great.  At 20.00 a pop for 5/8" bits at Home Depot I wouldn't be without it.Neil
Reply:I suck at sharpening drills manually, but that still doesn't stop me from doing it.  A guide really does help.  Generally, I don't sharpen anything smaller than 1/4" as those can be purchased from a tooling supply in copious quantities for cheap.  To sharpen a drill on a bench grinder, a good square tool rest is required as well as a decent dressing tool.  I've had to school all of my friends and cohorts in this regard as their grinding wheels are usually all rounded and sad looking.-Heath
Reply:I've got a couple of dozen blunt drill bits at home. Not small ones - I toss them out when I bugger them up.What on earth is a drill doctor? Anybody got a picture?Scott
Reply:Go to:    drilldoctor.com i e=received one as a gift, I don't know if I would have bought one for myself, but after owning one, I want another one to put in my service truck. Well worth the money, does a great job!Just my  opinion, not from a book, just from the road.Howes Welding Inc.www.howesweldinginc.com
Reply:Looks like they're not available in 240 volts. I guess there will be something similar out here - probably a Chinese copy.
Reply:Hi Scott,"Drill Doctor's" are available in Australia.Not sure if you have a branch of "Total Tools" up there in Sydney, but they started selling them a few months ago.I watched a quick demo and was impressed. Takes all the quess work out of sharpening.We really get shafted on the price though. There are only two models available here so far, and the basic one starts at over AUD360. The next one up (which can do split points) was over AUD550! I was going to get one from USA through Ebay for around USD100, but the voltage difference stuffed that up.Might still be cheaper to get a US model and a 115 / 240V transformer........
Reply:You got me thinking about the Drill Doctor again, Scott.Now I really want one again.Did a quick Google on "drill doctor" for Australia, and there are a few other companies selling them here.I will let you know if I find a good deal, but so far they're still around the $400mark.
Reply:If the price disparity is that large, get or make a step down transformer.  You will probably want other tools which may only available for 110 or 120 volts. To wind your own see post 31 here http://www.weldingweb.com/vbb/showthread.php?t=752&page=3. For an easy wind get two microwave transformers and seperate the primaries from the core.   Take one of the primaries and unwind half of the turns.  Assemble both windings one a single core and you should be in business with 110/120 volts on the reduced winding.  For higher effiency a larger gague should be used in the new secondary so as to fill most of the available core space.
Reply:an old timer an (old) shop teacher showed us if you take two  nuts and place them flat side to gether u will have the angle of the drill bit . its a good guide then it just practice as to get the taper off hope that helps--but a ele.sharpener is faster
Reply:Last I knew the chinese haven't made a viable copy of this machine yet.   Might have something to do with pattens that are still in effect.In any event do  consider a step down transformer for 110 volt tools.    While I find it hard to believe that the voltage of the tool has any impact on its price, people in Europe and down under do seem to pay a high price for their tools.   While I'm most familiar with England and Ireland, it does seem to be a general truth.In any event like I mentioned previously the machine seems to do much better than it has a right to.    It is incredibly small and light weight yet in may cases has put an edge on drills that are better than new.    I do maintenance work for a medical device maker and thus end up drilling stainless often.    Used properly you will get a good cutting edge on the tool (drill bit).ThanksDave Originally Posted by scott brunsdonLooks like they're not available in 240 volts. I guess there will be something similar out here - probably a Chinese copy.
Reply:I went to night school in machine shop at LA trade tech in downtown LA, and the instructor would not let you touch a single machine tool- and they had 3 shops full, well over 100 in all- before you could sharpen a drill bit, freehand on a grinder, 3 different ways. So I learned.Some of the guys were still trying in December- we started in September- but I wanted to get my hands on those lathes and mills, so within a few nights, I had it down.And its like riding a bike-once you learn the trick, you can do it for the rest of your life. My bits dont always look like new factory bits, sometimes I need to go back and tune em, but I can sharpen anything from about 1/8" to 2" by hand, and it will drill, and give off 2 corkscrews of swarf. One of the skills I am most happy to have learned.I use a 12" disc sander with a blue alumina zirconia 50 grit disc on it- sharpens drill bits in seconds. I have both a General Tool, and a Starrett drill bit gage for checking the angle and symettry- I actually prefer the cheaper General, as it is easier to read.From what I understand, the Darex drill bit sharpeners are supposed to beat the pants off the Drill Doctor.
Reply:FWIW, I have a magnifying class that I use to check the angles on the drill bits I sharpen using the pedestal grinder.  You can readily tell if you are grinding one side more than the other....- "If ya can't be handsome, ya may as well be handy!"   HTP Invertig 201Lincoln Power Mig 255CLincoln SP125+Thermal Dynamics Cutmaster 38
Reply:For the guys who have a drill dr., I have one and have problems sharpening small fluted bits. The flutes seem to keep the bit indexer from properly positioning the bit and I wind with not enough backcut?,I think that's the right term, and the bit won't cut at all.  Just curious if anyone else has this problem or if I'm not doing something right.The small fluted bits are the only ones I have trouble with.             Thanks,                       MikeOl' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:I've had that problem as well.  I thought it was only me...  I have access to a local shop that has the Darex sharpener system and that unit does my fluted bits just fine.....but the unit is not cheap.  I'm "campaigning" with the wife for a Darex system for Xmas....
Reply:Originally Posted by scott brunsdonLooks like they're not available in 240 volts. I guess there will be something similar out here - probably a Chinese copy.I get mixed results on the smaller bits, usually under 3/32", with the Drill Doctor.  Sometimes they work great, some time they skate real bad. Ebverything larger works great
Reply:Good to know those Drill Doctor things are available here. Not so good to know the price. Hard to justify for the amount of times I'd use it. And by the time I got my head around a step down transformer and got a Drill Doctor from the US sent over it would end up costing me around what they cost here.If some of my friends had the slightest interest in anything mechanical I would go halves with them in a Drill Doctor. (I would also go halves with them in a trailer, a cement mixer, a panel saw and a dozen other things I would only use occasionally.)I might have to teach myself to sharpen drill bits on a grinder.Scott
Reply:bench grinder here too
Reply:I know a lot of people are convinced that they can sharpen drill bits manually as well as any machine but until you start working with machined sharpened drill bits  you won't see the light.   Belive me I was brought up by my father sharpening drill bits on a grinding stone mounted on an old motor as he wasn't willing to spend the money on an actual grinders.   so I know what the other side of the fence is like.   The drill doctor is from the other side of the fence, it isn't even a general purpose grinder rather a task specific machine.   The thing that makes it so attractive is that it does so well and is rather cheap.   It is very cheap once you start to realize how much good quality drill bits cost you.   Frankl I find the machine faster than attempting hand grinding.   Furhter as I age a bit the old eyesite isn't what it use to be so the drill doctor wins there to.As to going in halves, that is something my father was into also.   Sometimes it worked out real good other times not so good.    A better approach with the drill doctor would be to charge your neighbors and others for the bit sharpenings.    Might as well derive a bit of income off the machine.    If it is expensive make it pay for its self, sort of like finding an ideal wife.As Darex; if my info is correct they are the instigator of the drill doctor.   The drill doctor is basically a light duty version of their industrial models.   The "company" marketing the drill doctor is or was part of Darex, and is a way to keep the proefessional and semi professional stuff seperated.    I say semi professional because the mahcine has yet to catch on with the home market the way it has for some trades.Dave
Reply:Originally Posted by scott brunsdonGood to know those Drill Doctor things are available here. Not so good to know the price. Hard to justify for the amount of times I'd use it. And by the time I got my head around a step down transformer and got a Drill Doctor from the US sent over it would end up costing me around what they cost here.If some of my friends had the slightest interest in anything mechanical I would go halves with them in a Drill Doctor. (I would also go halves with them in a trailer, a cement mixer, a panel saw and a dozen other things I would only use occasionally.)I might have to teach myself to sharpen drill bits on a grinder.Scott
Reply:Never thought of using a stone, that is a great idea.  I don't have a bench grinder yet, but have a some good experience on the stone.  If you put a chip on the edge trying to drill sheet metal, you're still out of luck, though.
Reply:Originally Posted by 76GMC1500Never thought of using a stone, that is a great idea.  I don't have a bench grinder yet, but have a some good experience on the stone.  If you put a chip on the edge trying to drill sheet metal, you're still out of luck, though.
Reply:Scott, you fellas down under say you have 240 v as opposed to our 110v. Is this 240 v on one hot leg and a neutral? From what's been stated in other posts,I'm assuming so, but assuming has got me in a lot of trouble over the years.              Just curious,                              MikeOl' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:Originally Posted by mla2ofusScott, you fellas down under say you have 240 v as opposed to our 110v. Is this 240 v on one hot leg and a neutral? From what's been stated in other posts,I'm assuming so, but assuming has got me in a lot of trouble over the years.              Just curious,                              Mike
Reply:Brett,Just wanted to welcome you on behalf of Welding Web.  Hope you enjoy your visit and if you are interested we have an introduction section where you can share a little about yourself.  So take of your shoes and make yourself at homeIF it Catches...Let it Burn
Reply:Drill Rig for $10I have attached a picture of the drill sharpening rig that I use in combination with either a bench grinder or a 4.5 inch angle grinder.  This unit costs less than $10 and is available in Canada from a number of suppliers like Princess Auto and Busy Bee Tools.  In my experience, this device works well with drill bits from about 3/16 through 1/2 inch.In use, you position the drill in a V-block, rotate the drill in the 'V' until you catch the edge of a flute against a pointer, lock the bit, grind that flute swinging the assembly to grind the relief from the cutting edge.  OK for one side, then you release the drill slightly, rotate the drill 180 degrees in the V-block until you catch the edge of the second flute against the pointer, then you grind that 2nd flute swinging the assembly to grind the relief from the cutting edge.The problem is small drill bits, most importantly 1/8 inch - that I use all the time!  The pointer gets hung up in the flute when you try to rotate the bit 180 degrees for grinding the second flute.  Usually, you have four problems - most all from having to rotate the bit for the 2nd grind:1 - the small drill get hung up in the pointer - changing the grind angle.2- You cannot reproduce a 180 degree rotation and the grinding is off.3 - The grind is affected by rotating the entire drill shaft in the V-block - any burr on the drill shank and the grinding is off.4 - Any unevenness of bottom of the drill shank and the grinding is off.I tried to fix this by modifying one of the units to hold a standard 3/8 inch capacity drill chuck in a set of precision bearings.  I place the drill in the accurately rotating chuck - thereby avoiding problems 1, 3, and 4; I can also get a pretty good 180 degree rotation (1) with a few degrees.  Surprisingly, while better; doing 1/8 inch bits is still difficult.The problem with small diameter drill bits is that the twist is so fast that a small error in angle or linear position (fraction of a millimeter) has larger consequences - that would hardly affect a larger diameter drill such as a 1/4 inch drill.The fast twist and small diameter make it difficult to set the drill flute against the pointer just right; if you are off - you get an improper cutting angle.  Hey, even if the angle of the grind is perfect but you take off a mite too much metal - because of the fast twist - you just significantly changed the angle of the cutting edge with respect to the drill face.  AHHHhhh!I had a look at our professional drill sharpening rig at work - in the machine shop.  This BIG PRO unit has a 1 hp motor, massive grinding wheel and uses a hollow 6 jaw chuck to hold the drill bit - up to ~2 inch diameter.  There is a precision stepped pointer to catch the flute angle for set up.  Then, you simply turn a handle that rotates the drill chuck via an eccentric cam.  The resulting precision wobbling motion grinds the drill's 1st cutting edge, grinds the relief then removes the drill from the grinding stone, rotates the drill 180 degrees and grinds the 2nd cutting edge and the relief.  Whoa - beautiful ... but beyond me to build.Anyway - my set up is cheap and overall it's not too bad at all.For 1/8 inch drills, if I want factory-like performance , I just have to buy em in bulk.Rick V Attached Images
Reply:I like the sound of that thing. There will be something like that out here. I have about 20 blunt drill bits from quarter inch to half inch sitting in a box in my shed.Scott
Reply:I have used bench grinders, belt sanders and files. For the buck and a half you spend on a Drill Doctor 750X you will never go back. It is some of the best money I ever spent. I dont have a bench grinder in the field, and it saves so much time going out to buy a new bit. Why do we buy drill bits when we only want the hole?Disclaimer; "I am just an a$$hole welder, don't take it personally ."
Reply:I haven't had much luck with the drill doctor.  It does ok, but I can sharpen them better on a belt sander in about the same time.  No one else at the shop likes it much either, they come get me to sharpen their bits.  If you get the basic angles down it's easy.DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. tools
Reply:I also use the drill rig Rick V talks about. I use mine on a grizzly 12" disc sander and it puts a razor edge on a bit on any angle you want, also makes perfect flat bottom drills i don't think you can do that on any other sharpener...BobBob WrightSalem, Ohio  Birthplace of the Silver & Deming Drillhttp://groups.yahoo.com/group/southbend10k/http://groups.yahoo.com/group/sawking/1999 Miller MM185 w/ Miller 185 Spoolmate spoolgun
Reply:IT-Welder  I just looked at the video on Drill Doctor's site and the guy came out and said it was made by Darex and uses the same technology as the Darex sharpener.  Check out the video.
Reply:I have several of these units. They are Vintage Craftsman Drill Sharpeners but they work perfectly. I mounted one of mine on a 1/4" steel plate with a 1/4 hp 1,750 rpm motor with a 6" fine disk. They work well on from 3/16" to 1" drills. They give the exact angle for proper drilling. I've been using mine for more than 30 years. It belonged to my Dad and I bought two more for backup. They are usually about $10 on eBay. Attached ImagesLast edited by gnm109; 10-18-2006 at 09:14 PM.
Reply:gnm109: I have several of these units.
Reply:Originally Posted by Rick VThanks for posting that high definition picture; it is a lot clearer than mine!Yep - that's the same rig.I didn't realize that it had been available for 30 years!While nothing is perfect, this unit is good value (cheap and it works... according to aametalmaster, it even makes perfect flat bottom drills) - and it is highly adaptable... use it with a 4.5 inch angle grinder, disk sander, belt sander, on the side of a bench grinder, etc.  All that for less than $10![Hey, this sound like a TV advertisement! ... and if you act now, we will throw in...]Rick V
Reply:Originally Posted by Rick VI didn't realize that it had been available for 30 years!Rick V