Sharpen Your Drill Bits

Sharp drill bits are fun to use. They work so well. Dull bits are dangerous. They can break. One broke for me once and went through my thumbnail and out the other side of my thumb.

Step 1: A dull bit and a sharp bit

The bit on the left is a little dull. Notice the glint of light on the cutting edge between the two flutes. Compare that with the crisp edge on the freshly sharpened bit on the right.

Comments

[bakichmg]

I recently purchased this sharpener. I am totally confused by the instructions that came with it. I am glad I found your instructable. But I still cannot figure out the proper position of the bit. Which way is the bit supposed to be twisted in the holder?? I have tried it may different ways and the grinding angle comes out wrong. Can you please help me?? Do you possibly have a close up of the bit installed with the proper orientation??

[Phil B]

Do the photos and the descriptions in steps 4 and 5 make sense to you? If not, what puzzles you about them?

[bob Cosenza]

Machinist by trade, machine grinding is ok, but even with this drills are touched up by hand, back clearance and the web is thinned out ( aircraft colbolt drills) by hand.

[anode505]

I disagree with the ability to sharpen by hand. Yes it will be sharp, but right? Doubtful. Unless both sides are even, it will not cut the correct sized hole.
People that claim they can do it are just lucky once in a while. I say test a hole with a pin gauge; you'll find its cutting large.

[Bowtie41]

As a machinist for 25 years I have to disagree.One of the 1st skills taught was how to sharpen by hand with a simple drill point gage.I remember a job over 20 years ago that we had to use a 1/32"(.031) drill to peck drill about 3/4"(.750) deep in stainless.They would not fit our drill sharpeners,and since I was one of the better sharpeners there,I got the task of setting at a grinder with a large magnifying glass,and a sharp edge orange wheel,and doing it "old school".As I sharpened several hundred bits for the screw machines,I had approx. 1-100 I would get an oversize hole or the bit would wander off-center and come out the side of the part,and I would have to resharpen again.I am not saying that to brag,just that there are literally thousands,maybe tens of thousands of us out here who do them by hand.I can't even remember how many I've done over the years,including split points,and making special diameter stepdrills,but it amounts several,several thousand.It is not a hard skill to master,just decent eye-hand coordination,but does take patience,and attention to detail at first.

[ArtisanEclectic]

I have sharpened many bits by hand on a bench grinder. It only takes a little practice and attention. I've used them to drill wood, plastic, aluminum, and stainless. Although I usually buy new Carbide bits for stainless. It's not rocket science. And I don't believe in luck.

[Bowtie41]

I would like to add unless the carbide drill is about 1/4" or larger,to try not do it by hand,as carbide is very brittle,and any side-force just breaks them.Normally,any carbide drill should be in a press or mill with a rigid spindle.

[stoobers]

The hole down the center of a gun barrel is cut with a drill bit with a SINGLE flute - not even a double flute! And the hole is straight and true for several FEET.

You don't need two sides to the bit to make the bit cut. If you have a bit with two flutes, the bit will cut twice as fast as a singe flute bit.

Upon close examination, a two-flute bit will cut a triangular shaped hole! (trochoidial shaped). If you want the hole round, drill it 1/64" under and ream it out. If you need to thread the hole, you can skip the ream.

[HoldOnTight]

I used to have one of these tools and I could never get a sharp bit with it. I'm happy that this tool works for you but it seems as though I couldn't get mine "dialed in." Replacing a bit every time one became dull was getting expensive. This tool probably doesn't handle the specialty bits with cuts to reduce friction, but a Drill Doctor does that. The diamond wheel on a Drill Dr. removes material very quicly, before the metal can heat up and destroy the hardness.

[shazni]

how do i shapen a spiral scroll bit which is supposed to cut sideways too?
it's 1/8"...i use it for my rotary tool and i only can get new once from abroad

[Phil B]

I would get a fine, hard stone like a hard Arkansas stone and dress the bits by hand. It is not perfect, but it might help you.

[shazni]

how do i shapen a spiral scroll bit which is supposed to cut sideways too?
it's 1/8"...i use it for my rotary tool and i only can get new once from abroad

[flywelder]

Phil or any body,
I have inherited three drill bits made by the Union Twist Drill Co. a No. 8,
No. 6; and No. 9 They need sharpened, and I have yet to find any one who can sharpen these or tell me how to . the interesting thing about these bits is they each have three cutting edges. yes three. there is a pencil point surrounded by three flutes. Help.
3-01-2012

[Phil B]

Wow! I have heard of numbered sizes. When you want to drill for tapping threads the recommended bit is usually a numbered size. But, I have never heard of a bit with three flutes. I would ask questions at a local machine shop to see if they can help.

[ronbuffington]

I thought these were called drills, not bits. Drills may be used with drill motors, but bits are used with a brace, i.e. a brace and bit.

[quahogwi]

I'm a little late getting into this, but the compulsion do do so is overwhelming. The distinction is simple. A drill is the machine or tool or action used to make a hole in some material or other, usually a hard material. A drill bit is the cutting piece or edge of the tool that makes the hole. There may be minor nuances as to where the ":drill" ends and the "bit" begins, but at it's core the drill is the tool, whether motorized or not, while the bit is that part that bites into and removes the material and actually makes the hole. So, you sharpen the bit and not the drill itself.

[quahogwi]

I failed to mention that I thought this -able very good and worthy of downloading the pdfl.

[Phil B]

You are probably correct. What I wrote reflects what I have heard all of my life. I expect others have heard it as I did, too, whether right or wrong.

[ronbuffington]

Phil,
I should not complain, father being a carpenter, drilled, into me what a drill was.
you and i are same age , different backgrounds. Good Work.

Ron

[Phil B]

Ron,

That reminds me of something my mother drilled into us. She was a registered nurse. My brothers and I were the only kids in our one-room elementary school who could tie a tourniquet. Further, if at age 5 or so, multiple people needed one, we were to write TQ on their foreheads in lipstick so we would know to come back and release the tourniquet periodically so that the tissue beyond the tie point would not die. I do not know where we were to find tourniquets or lipstick, and I do not know that anyone would ask a 5 year old to handle such things, but we were trained and ready.

[GadgetBuilder1]

Drills with grind lines parallel to the lip tend to fail prematurely due to flex at one of these grind lines. See the picture here for an example of this failure:
http://www.gadgetbuilder.com/DrillSharp.html#Inexpensive

Raising the contact point well above the grinder shaft avoids this problem.

[montanasoftware]

Excellent writeup ... you are a wealth of knowledge. I also enjoyed your DIY radiator pressure tester, and have already assembled a brass T-Fitting for heater-hose access.

Thanks!

[Phil B]

Thank you. I am almost older than dirt, so I have had time to learn a couple of things. Thank you for starting on the radiator pressure tester. I would be interested in seeing a photo of your T-adapter sometime.

[msw100]

Is all this not automatic with a bit sharpener,I do mine by hand on a grinding wheel and they are as sharp as any done on a machine

[marksteamnz]

Hi Great instructable
Just wondered why in step 12 the tip appears to be dragged across the grinder face before starting the wheel and then swung back. Would it be better to swing to the left, start the wheel and then swing to the right?

[Phil B]

The answer to your question is that the post on which the jig swings is not exactly vertical, contrary to expectations, but it has a forward caster that causes the bit not to make contact with the wheel where in its swing arc you would expect it to make contact. You can get a hint of that forward caster by looking at the profile photo of the jig in step 2. Compare the plane of the jig's base on the bottom with the slight forward angle where the base connects to the upper part of the jig. If you are familiar with the three angles involved in aligning the front wheels on an automobile (caster, camber, and toe-in), this will make more sense to you. Step 13 gives a better impression of where the tip of the bit is when it makes contact with the wheel. Also, I like to swing the tip far enough to the right before starting the motor so that there is plenty of clearance and no possibility the bit and the wheel are in contact with each other when the motor starts. Thank you for your interest and for looking.

[inad]

This is a great series. Wonder if you could do a parallel instructable showing free hand held technique for sharpening drill bits. some oblique photos would be a great help.

[Phil B]

Thank you. I am glad you like it. I hope it helps you when you sharpen drill bits. If I had mastered sharpening bits by hand, I would gladly do an Instructable on the process. I did find a couple of pages that briefly describe how to do it, and alluded to the basics early in this Instructable. Perhaps one of the previous commentators who has learned how to do it would consider producing such an Instructable. I do not believe myself to be qualified to do it.

[jack8559]

I don't have access to a camera or recorder, but there is a book that may help if you can find a machinist or engineer that will let you look through their copy. It's called MACHINERY'S HANDBOOK. The book is expensive, at least by my standards - around a hunderd bucks US money. There is a wealth of information in there on a lot of things mechanical. You may be able to find an old used one on ebay or someplace for 30 or 40 dollars - well worth the money!

[jack8559]

As a machinist, I have sharpened thousands of bits - all by hand. If they are really small (under 1/8") I usually just get a new one since we never had a sharpener that I had any degree of faith in. A note for everyone that attempts to hand sharpen a bit... always look to be sure that from the cutting edge that there is relief behind it. I have seen so many people that claim to be able to sharpen a bit and they come back with the trailing edge of the bit higher than the cutting edge and they wonder why it won't cut.
If a bit is going to be drilling hard material, you will want the end to be more flat so it won't dig in and dull fast, and you will ALWAYS want to center punch your mark to prevent a drill from 'walking'. The 59° angle used on most sharpeners is a standard angle for mild steel - for softer materials make the point more like a pencil but be careful of how much more pointed you make it, it could try to screw itself into the wood, plastic or whatever you're drilling. I guess my point is to go in small steps until you know what works for you!
Try starting with a large bit if you aren't familiar with the procedure and remember that if the steel gets hot enough to turn black at the cutting edge, you have just removed the carbon from the edge and it will dull VERY soon. You must grind the metal slowly and dip in water or some other coolant frequently so as to prevent that. Get a new bit to look at after you have tried your hand on a big one and see what the difference is, there should be very little. When thinning the web, remember that the thinner the web, yes, the easier it will penetrate the work, but also the easier it can grab and split the drill down the center making the drill bit trash immediately. If the sides (lands) are worn on the drill bit, it WILL grab and break off many times when you need it most - inspect drills before using them to keep from ruining your project... After grinding, hold the bit up with a bright background behind it and with the cutting edges going left and right from your body - you need to make sure that both the tips are the same height and that the point is in the center before you attempt to thin the web if it is needed. If there is a pilot hole with a greater diameter than the thickness of the web, no thinning will be required.
Whne grinding by hand, always hold the cutting lip level against the wheel at the center height of the wheel and rotate the drill upwards to make the relief. Grind slowly and don't try it with a wheel that is out of round, you will get hurt badly. Dress the wheel to be true before starting any grinding process. Always use safety glasses or goggles when grinding and if there are any questions, stop what you are doing and research it- SAFETY FIRST!!

[Bowtie41]

I know it's an old post,but Bravo!

[nedward]

do you use a slow grinder 1800 revs i am a qualified electrician from sout africa rsa southafrica i use a norton white stone on 2400 rev grinder small bench grinder i find the grey stones hard on the drill only use white wheel i come from a farm where we sometimes use an angle grinder for a quik sharp your article is exellent with safety and all is the relief part the thickside from the cutting edge downwards 118 degrees on the slope on both sides must be even it is an art to grind freehand but i cant sit in the field with jigs the work must go on blunt drills scream i also use lubricant when drilling electrical cuttinpaste nice talking to you nedward

[jack8559]

At work, I used a regular bench grinder, which means that you need to lightly touch the bit to the spinning stone, rotate the bit, cool it in coolant preferably, but just plain water will do fine, repeat until you have finally got it really close enough to suit you, then gently and lightly grind the finishing touches all the way from the cutting lip to the trailing side to get the relief right and cool it again. It takes a while to get it right. A great thing to do is get a new bit and never sharpen it, just use it to look at while grinding the old bit so that you know what you're looking for in the hand sharpened bit - use it as a comparison for the point.
The 59 degerees is the angle on one side of the bit to the centerline of the bit, so the 118 degrees that you mention is the same as what I'm doing. The finer the grit you use means that you will have to dip it in water or coolant more frequent but it will give you a better grind as well. I have used a 60 grit wheel and gotten good results, it's just a matter of taking your time and knowing what to do. Practice makes perfect, and then when you think that you've got it, then practice a lot more..... you'll see that there are ways to do the job and make it a lot faster and still not burn the bit! If you never have made the metal black or blue at some point during sharpening the first hundred bits, you have not really tried like you should. Know when it will turn blue and stop short of that. Small bits will turn blue a lot faster than larger ones due to the mass that will have to be heated from friction to cause it to turn color and burn the carbon out...

[Phil B]

The motor on my grinder runs at 3000 rpm. I use what I have available. I do not have a white stone. Thank you for looking and for commenting.

[MTJimL]

I thought I was good using a drill guide and sharpening by hand. Being able to accurately eyeball the slope, clearance and centricity without a guide seems truly remarkable.

[jack8559]

MTJimL:
This is not something that you can pick up in a few days, maybe not in a year. I have sharpened bits for over 25 years (daily) to do as well as I do. The first thing that someone needs to do when attempting to sharpen by hand is to really study drill point geometry closely. Understand all the parts of the drill and what their specific function is and why it is needed to be the way that it is. Once you understand all this, you must try a few thousand bits before you get it close enough to perform well for your application consistently.

One point to remember is that the angle of the point must be reasonably close to what is recommended for the application that you are going to use it for. the more pointed it is, the more it will tend to pull itself into the material being drilled, so that material must be soft enough not to split the drill down the web. The harder materials will be better served drilling with a much less point on the drill - almost a square end. The relief behind the cuting edge has a bearing also - hard materials need to have a relatively low relief (.001 to .003") and softer materials like wood should have a more pronounced relief(.010 to .020"). If a material is not drilling fast enough, it is probably due to the web being too thick and must be thinned OR the relief is way too shallow. Be careful to closely inspect the lands for drilling materials like bronze, this material tends to wear out the lands and the drill will grab and split the drill down the web and break off in the hole - not a pleasant task to remove. It takes some homework to fully understand drill bits even though they are as common as they are.

[tomas.savage]

good advice. i'm a jeweler and i sharpen my tiny drill (1.5mm or smaller) bits by hand all the time. i use an ultra-thin cutting disc and hold the drill in a pin vice. it was a matter of trail and error until i learned how to hold the bits and tools at the proper cutting angles. the cutting disc can even sharpen/deburr worn lands by running it through while rotating the pin vice.

[note: with this method, it is even possible to restore some life to other rotary tool bits, though i would use them for roughing work]

[Twicewidowed]

As an old time machinist (now 84 yo) I agree. Hand sharpening drills is an art learned over years of experience. Production drills should always be machine-sharpened however. Two equal sized spirals of blue hot steel emerging from a bath of cutting fluid is the mark of a well sharpened drill but having the ability to touch up a slightly dulled drill by hand is a real time saver and an indication of craftsmanship.

[baudeagle]

Great response, your comments above are in essence the same as what a mold maker taught me a long time ago.

One tip on drilling large hole, if using a pilot drill, use a small diameter drill compared to the diameter of the finished hole. The the pilot drill should not be smaller than the thickness of the larger drill's web.

Thanks for your comments.

[Phil B]

Thank you for a very helpful comment. Regular practice has to be a key component in the proper sharpening of bits by hand. Even if I was careful to keep the heel lower than the cutting edge, I had trouble getting the slope angle equal on both sides and with keeping the web centered between the opposing sides of the bit. I stand in awe of anyone who can sharpen bits by hand and do it right.

[grigsby]

Almost 70 YO. Journeyman Mold maker. Have sharpened a lot of cutters. Even spiral taps. Oh, I ground taper by machine and then cleared each one by hand. Then checked each one by tapping a hole in Aluminum. I have been told the best/worst joke is to substituts a left hand drill in machine when a new guy takes a break. I haven't tried it but have thots of some bad communications. NO I haven't done that. The best idea I have heard is to sharpen end of a drill blank left handed so broken bolt will screw out when trying to remove a broken bolt. I love it. Drill blank will look like a broken center drill, only with left hand cut. Yes, 1/16 drill can be sharpend by hand even tho I can't see end of drill.

[MTJimL]

When I was in the business I had to sharpen bits by hand; the owner was too cheap to buy a drill sharpening jig. I used a commercial, sheet metal angle guide/scale and a very light touch to finish the grind. I could usually grind them to cut within .005" of their nominal size. The hilarious thing is the owner could have bought a quality sharpening jig many times over for what he paid me to do it by hand.

What amazed me was how many production "machinists" had no concept of a properly ground tool. I don't know how many times I tried explaining cutting tool rake and clearance angles.

[Narlo11]

Hey grigsby I also make molds (fiberglass and concrete). Where did you get journeyman certificates? As far as I know there is no such thing. Im in Canada and have looked into it. All I know of is CCT. So I can say I am a journeyman but have no papers.

[grigsby]

I am in IN. I build molds for injection plastic parts. My journeyman papers were issued by US labor board. I also have certs for my shop to train moldmakers/ machinist. I own mold building and molding shop.

[dwhite0]

Sorry, but I do not see this device on Amazon. Would you be so kind as to give us more complee details on the sharpener: such as Manufacturer, model number and any othe identifying notations. Your phot reveals the word craftsman?

[Phil B]

Amazon has it under two listings. One is more than twice the price for the same item!

$7.99

$16.95

There is one company making and labeling them for whomever wants to sell them.  Just click on the hot linked price you wish to pay. 

[andrewuk]

Bought this tool on Amazon UK for those of us that are on the otherside of the pond.

Search for "Draper Drill Grinding Attachment" brilliant only £17.02

[weldor]

How about info on sharpening for hardened materials? For wood I was taught to sharpen the bit to a radical 90 deg so that the bit does not cause the wood to splinter when the bit exits the work piece. This actually works great!

[Phil B]

Perhaps some of the folks with more experience than I have can respond to this.

[howie57]

I just found your wonderful Instructable on sharpening drill bits. I have all ways thought about buying a sharpener but never knew it they really worked. Now that I have read your Instructable I am going to buy one and try it out. I have a lot of old drill bits of my own and a bunch from my brother who brought them home form his work. He is a welder and they throw away all the dull drill bites. What a waste. If I can get it to work they will have a new life. It's nice to be green.

[Phil B]

Howie,

Thank you. As you can see from the various comments, some people really like the Drill Doctor system. Others very much like sharpening by hand. I have always been pleased with the sharpening jig I demonstrated in the Instructable. I am just a guy with a home workshop and it does well for me. If you have many dull bits in all sizes you can have fun making gifts of sharp drill bit sets to friends.

[pfred2]

I have one of these and I noticed the grind marks are not perpendicular to the lip edge of the drill. So I made a holder for the sharpener that makes the grinds come out better. Sort of hard to explain so here is a picture:

[Phil B]

Clever. Thanks for showing this.

[pfred2]

If you try to grind different angles by adjusting the sharpener itself then everything goes out of whack again I think. At least I sort of remember some issue about that. Probably why they did not address the design deficiency with the unit. It'd have called for a complicated adjustable base or something to do it right. So they just made it bad all around and called it a day.

Someday I will have to revisit this hack and make a pivoting table for it. I'm seeing a little piece of angle iron that pivots around a hole in it and a locking bolt through it going to another plate.

But with the grinds perpendicular to the cutting lip then the edge is less prone to chip. Bits seems to come out sharper to me too. I don't know, all I know is I like it better this way. Fool around with it some and see what you think.

[jack8559]

...for most applications, a 118 degree point is acceptable, which means that you will have to offset the angle from the grinding stone's face 31 degrees to either side. For soft materials, use a sharper angle, like 60 degrees from the grinding face, or closer to a flat point for harder materials. This works well, but you may need to adjust your angle for tha material being drilled depeding on hardness (or softness). The softer the material being drilled, the more like a pencil point is desirable, such as softwoods.

[Kevanf1]

I love this ible, well done. I have one of the drill sharpeners but still have to remove it from the box....... When I get time.

The only thing I would add to your excellent tutorial is that different metals actually need different angles to be ground onto the cutting edges of the drill bits. A bit that will cut steel is not so good for brass or copper, for example. I don't know if the sharpener takes this into account?

Take care.

Kevan

[Phil B]

Thank you for your appreciation. One reason I do most of my Instructables is to document ideas and projects for future reference and for sharing. But, another is to inspire people like yourself who have a drill sharpening jig like this, but have not taken it out of the box yet. Just about all of my drilling is either in wood or mild steel. So, 59 degrees works for my needs. But, if you look closely at the photo in step 3 you can see the bumps for setting the jig to other angles commonly used for different bit needs. I highlighted the 59 degree bump with a permanent marker for the purposes of that photo.

[Kevanf1]

He, he, can't you just tell that I haven't taken my sharpener out of the box..... I would have noticed those other degree stops otherwise.

Actually, the only reason it is still in the box is because my drill bench is not very god surface wise. I need to reface it to make sure the grinder is sitting perfectly level all round. My bench drill is the only truly flat spot on the whole bench. I just got too carried away in making my other main workbench. Actually, it's a shame I didn't document that as it would have made a fantastic 'ible'. The bench is strong and would easily take the weight of about 3 or possibly even 4 big V8 engines. Yet, it is still light in weight (relatively) and made easily of wood. Anyway, this is going way off the subject of your excellent ible so I apologise.

Take care.

Kevan

[kill-a-watt]

Thanks for publishing this. My Dad has one and I never was able to get it to work. He didn't have the instructions. My (wood) shop teacher taught me how to do it freehand, but it's a perishable skill. Two decades later and I've lost my touch.

Shop Teacher, Machinist, and rising YouTube star Tubalcain has a few good videos. I'll warn you, he doesn't much care for your kind of sharpener.

I do my 1/2" and larger freehand again thanks to that video.

About a year ago, I had some long shank drill bits (~$15 each) that I needed to sharpen, and I broke down and bought the DrillDoctor. I'll Nth the fact that it works well, keeps them sharp, and lets me quickly resharpen if needed.

If you think you'll buy at least 33 twist drills in the next 10 years, I say the Drill Doctor is worth it, Doubly so as I don't have a grinding wheel around to use with your style of fixture yet

[Phil B]

Thank you for your comment. I will look at the video for hand sharpening. Thanks for the information that this is a perishable skill. I wondered about that. A Drill Doctor would be nice, but I use my fixture only rarely. It has been great when I needed it, though. I have attended the funerals of several people younger than I am, so I think twice before buying a lot of long term items, unless I plan to pass them on to someone in my family.

[somebullcrap]

out of all the ways out there to sharpen drill bits .it is by far worth the price to just buy a drill doctor .they are as easy to use as the commercials show .again they are pricey ,but like i said well worth it in saving time and headaches

[Phil B]

Perhaps buying a Drill Doctor is a good strategy for someone with no tools for sharpening bits. When I bought this tool it was just about the best device available. It still suits my needs and I am not about to replace it with a Drill Doctor at this point in my life. I barely use what I have enough to justify owning it.

[somebullcrap]

i'm sorry if i implied your instructable wasn't of use .because it is great to know how to properly do this using more involed methods .i was just trying to say for myself ,having tried all the other methods of drill bit sharpening the drill doctor is the easiest i've used ,but if you only sharpen a few bits a year there is no justification of buying one anyway great instructable

[Phil B]

Thanks. I took no offense. I am also 63 years old and I think twice before buying something I will not use a lot.

[static]

Sound like my dad Phil. Thinking the money he didn't spend on himself then he could somehow take it with him. That or your expecting a frail old age

[Phil B]

When I was growing up I frequently heard stories about what it had been like to live through the Great Depression. Those stories plus living with very little extra money for discretionary spending in the early 1950's infused me with a "waste not, want not" mentality. It really has nothing to do with thinking I will take it with me.

[jack8559]

I agree totally Phil, that money can be used for something else that you want or need. A savings is just that, savings. If a friend has a tool that they don't mind loaning you once a year, do it and return the favor for them also, it saves you both money.

[godfish]

Sir I want to think you for putting this info out here for us, this kind of info is so hard to come by these days, Ya the info is on the web but to have someone show you the steps and with such detail like a grandfather would show a grandson. Just a great thing. I own a Drill Doctor and its a good thing, it does the job very quickly. I just had to drill a lot of stainless steel and that stuff really dulls the bits. A Drill Doctor is a good way to save some money and get the job done, your way is the way of the craftsman, a lost art these days. Hats off to you.

[Phil B]

You are very kind. Thank you.

[HarryMann]

Yes, that edge is commonly called the chisel edge of a drill. It is indeed a good guide as to whether the sharpening has been succesful. The cutting edge ideally wants to be straight rather than curved, though its often hard to determine why it won't come right with some drills...

[aufer2ooo]

Starrett makes a great little tool to help when sharpening drill bits...
It is a gauge fixed at 59 degrees with 32nd increments to aid you in finding center.  If you want to take a look google "Starrett 22c".  It does have two down sides.... the first I already mentioned it is fixed at 59 degrees the second con would be that its bare steel and will oxidize just from your finger prints unless you keep it lubricated...
I personally say sharpen your bits free hand.  I only say that because I need to sharpen bits at different degrees and change the lip relief depending on the scenario.  I have yet to find one tool or gauge that allows me to do it all...
Just make sure your abrasive is smooth. No less then an 80 grit equivalent.  After all the factory uses a diamond wheel.
I have more to say but I'm already rambling

[Zaphod Beeblebrox]

ouch

[TickTock]

Thank you for taking the time to provide guidance notes on the use of the drill sharpening jig. Like many others I have difficulty in making sense of the minimal information provided with the unit. Although things are clearer now, there are still a few aspects I can not figure out. When sharpening a drill bit by hand using the wheel face (as taught during my apprenticeship) the cutting lip is positioned horizontally. With the grinding attachment, the cutting lip of the drill is nominally vertical - so I am confused. This is mainly because logic tells me that sharpening a vertical cutting lip would result in the lip being concave due to the curvature of the grinding wheel. For example, a grinding wheel diameter of 125mm sharpening a 20mm diameter drill bit the cutting lip concavity would be in excess of 0.2mm (assuming my trigonometry is correct). Concavity would still be present for a drill 3mm diameter, but smaller. Obviously with a larger diameter grinding wheel any concavity would be less than indicated above. To be able to keep the tip of both small and large diameter drills aligned with the shaft centre of the grinder implies some form of height adjustment of the jig. Presumably failure to change the height would alter the point angle. One final point, there is no mention about sharpening quick or slow helix drills and their possible impact on the parameters to be used – in particular the amount of overhang required.

[Phil B]

I am hardly an expert, but I think the mystery over the difference in bit attitude when sharpening by hand (cutting edge horizontal) versus sharpening with the sharpening jig I showed in the pictures (cutting edge vertical) is in the position of the axis pin about which the bit is rotated. When sharpening by hand, it is as if there is an invisible horizontal axis. When sharpening with the jig shown here, the axis pin is vertical, even though there is a forward caster. The photo of this jig where it is sold on Amazon.com shows grinding from the flat side face of the grinding wheel. The wheel I used is fairly large in diameter, so the actual area of the wheel that does the cutting is reasonably flat, even though a little concave. I have most often done the grinding on the flat side face of the wheel. Yet, for safety reasons grinding on the flat side face of a grinding wheel is generally discouraged. I chose to show photos where the bit is being ground on the edge of the wheel, lest I open myself to criticism from some very eager member of Instructables who knows you really are not supposed to grind on the side of a wheel. I do not have any bits as large in diameter as 20 mm. My largest twist drill bit is only 1/2 inch (12.7 mm) and the bits I sharpen do not suffer from a concave profile. I am fortunate in that as I noted I use a radial arm saw for my bit sharpening. It has a crank that allows me to raise or lower the grinding wheel as I wish. If I had only a bench grinder, I would probably simply grind on the flat side of the wheel, despite the safety warnings. As you may have noticed, the meager instructions with the sharpening jig include overhang recommendations for bits of different profiles. I am not sure what angular profile slow helix drills use. If a bit has an 88 degree profile, the overhang recommendation is zero. I also learned years ago that if you cannot sufficiently reduce the overhang, you can compensate by turning the bit a very few degrees clockwise (as viewed from the sharpened end of the bit) before locking it down in the jig's trough. As I also noted, the overhang recommendations are probably best used when regarded as a starting point. Examine the bit after sharpening and check the lay of the cutting edge between the low part of the flutes. I hope some of this helps.

[TickTock]

Thank you for your frank answer it gave me the confidence to try using the jig. Although I experimented for well over an hour I am not yet convinced that I have the technique mastered. The cutting lip angle worked out fine and the chisel angle between the cutting lips is of the right order. The aspect that I need to sort out is the amount of overhang to get a sensible lip relief angle. I understand that the greater the drill overhang the smaller the lip relief angle and vice versa. The problem being that the lip stop does not permit much variation in the overhang. The best I could come up with was a fixed half helical increase in overhang. Having examined both options I considered that the short overhang gave a very large lip relief angle. Unfortunately the larger overhang resulted in an almost zero lip relief angle. I get the impression that something in between would be best. Any suggestions on how to proceed would be gratefully received.

[Phil B]

I hope I understand the terms for the parts of a bit as you know them. I found a diagram for parts of the bit at: http://www.drilldoctor.com/ftproot/Drill_Bit_Anatomy.pdf but it does not include some of the terms you use. It might be useful for helping us to understand one another.

I generally have not had difficulty using the jig, once I got the overhang right. But, I recently lent it to a friend and began to demonstrate it for him. I was having problems with some sizes, but not with others. I tweaked the overhang and the distance from the grinding wheel. His set up was not ideal, but eventually we got reasonable results.

After posting my Instructable I happened to see some notes I made years ago about using the jig. I believe the notes applied mostly to smaller sizes (between 1/4 and 1/8 inch). I was finding I could not reduce the overhang enough to get the results I wanted. What I did to compensate was to rotate the bit clockwise a little so that there was a small gap between the cutting edge and the adjustable lip stop on the jig against which the cutting edge would normally rest. I think I eyeballed the gap back when I made the notes. Now I think I would use a feeler gauge for consistency when flipping the bit half of a turn to do the other side.

I have never tried it, but it would be interesting to change the angle of the jig to the grinding wheel so that it no longer sits at the recommended 90 degrees to the face of the grinding wheel. Rather, the base that attaches to the table would be ten or so degrees less than 90 degrees to the grinding face. I have not tried it, but am thinking it might help.

[TickTock]

I found it interesting that the drill terminology I used was not familiar to you. I thought I was being clever by using the terms found on the minimal notes that accompanied the jig. Therefore I used some terms I was not familiar with because I normally use the anatomy terms in the Dormer (Sheffield, UK) drill handbook. Not surprisingly the Drill Doctor anatomy terms closely match those in the Machinery’s Handbook which refers to the ANSI standard. Anyway I am pleased to accept your suggestion of using the Drill Doctor anatomy terminology. To be honest I am not impressed with the design of the lip stop finger on my jig because of its fiddly method of adjustment and clamping. I feel that this aspect significantly contributes to my problems with trying to get a sensible relief angle. With the variety of drill sizes I tried to sharpen some results were more successful than others. Even with the same drill the results were variable. I have considered making a new lip stop – one that is more positive and easily fixed in position. I also wonder if some form of overhang adjustment could be built in at the same time – possibly a series of lip stops that provide incremental amounts of overhang. I suppose this is a variation on your gap / feel gauge comment. I had not thought of altering the base angle to the grinding wheel. I need to find the time to look at some of the built in angles with the jig. I can then decide which option to try first.

[Phil B]

Do not be too disappointed in me that I did not remember the drill bit terminology from the jig's instruction sheet. I read that 30 years ago, learned the process of sharpening my bits, and have not read it since. A person does not remember every technical term after 30 years, especially when that person does not work with drill bit terminology every day. (I would also want to check my instruction sheet to make sure the edition I have contains the same terminology you found in yours. My jig was sold by Sears and they may have printed their own instructions. I have seen that before. But, I cannot check it now because I lent my jig and all that goes with it to a friend.) You are disappointed in the way parts of the jig are constructed. I do not know what you expected, but I think my jig is made like yours and I have always found the various parts to be quite adequate to their individual function. Also, please remember I have sharpened every bit in sizes between 1/8 and 3/8 inch, and a few up to 1/2 inch in size. I have gotten very good results with the tool, even if I did have to tweak the setup on certain sizes to do it.

[samsaint1]

This is not the right way to sharpen a bit.You have to thin the web.This bit will not even drill a hole.You have to split the line between the teo flutes. This is what takes a real drill sharpener do it right.Also each flute must match. They have to be the same angle, and the same length.Also not all drill bits are 118 degrees.There is a lot more to know then this is showing you. you are better off using a sander, and try to get the angle correct.always take the same amount off of each side

[Phil B]

I assume you are writing about the finished bit I showed in step 15. Surely you overstate your case when you write, "This bit will not even drill a hole." I have been using this sharpener since about 1978. I have used it continuously to sharpen bits I regularly use for drilling wood, plastic, and mild steel. The bits I sharpened have always performed as well as a new bit. I acknowledged not all bits are a 59 degree profile (that is, half of 118 degrees), and that settings are different for other profiles. I also mentioned the instructions with the sharpening jig state very clearly that it is not intended for industrial applications.

[Sandisk1duo]

seems a little complicated! i'd rather buy a new set of drill bits

[sensoryhouse]

If you throw away dull drill bits you may as well throw away your Lithium-ion drill when the battery dies. They make the same amount of sense.

[Sandisk1duo]

see, i don't have an angle grinder using your analogy, throwing away a drill with a dead battery; if the replacement battery costs WAYY more then the drill, why not buy a new drill?

[berserk]

If you think of them as disposable, you probably buy them cheap to start with (so do I...). However, a lot of the cheap ones are not that sharp or properly angled to start with. If you have a pile of half inch holes to drill in steel or aluminum, you will be amazed how much faster and smoother it goes if the bit is sharp. And, see Phil's comment about safety.

[JerryMopar]

thats silly, unless you have HF cheapos. even then, a little practice freehand on a grinder, and you could stretch that money you spent longer

[chalky]

nahhh remember "A DRILL BIT IS FOR LIFE NOT JUST FOR CHRISTMAS" LOL:)

[Phil B]

Read what I wrote in the Introduction about the dull bit that broke and went through my thumb. If your strategy is to buy new bits rather than sharpen your old bits, you will use the bits longer than you should after they are dull. That means you will push down too hard on them, and that means one will break one day. If your hand is holding something down near to the target hole get ready for a drill bit injury.

[sensoryhouse]

Here's a link to the sharpener for $10.

http://woodworker.com/cgi-bin/FULLPRES.exe?PARTNUM=801-779

[sensoryhouse]

looks like a lot of people have followed the link. Woodworker.com nows says "LIMITED TO QUANTITIES ON HAND" regarding there previously $10 priced drill bit sharpener.

[sensoryhouse]

here's a pic.

[Phil B]

The cost of living index has gone up by a factor of about 3.5x since I bought mine. It is amazing to find something that is the same price or lower after all these years. Thanks for finding this. If someone takes a little time to learn how to use one of these, it does a very nice job for the home user, as good a the Drill Doctors would do, but for a lot less money.

[sensoryhouse]

Maybe you could add the link to your 'ible, since most people will probably need to buy one. Just a thought.

[Phil B]

Oops! You were the one who gave the link and the photo!

[Phil B]

Early in the Instructable I mentioned it is available at Amazon. A fairly general search on their site turned it up for me. One comment asked for more information and I mentioned it is listed at Amazon as the Grizzly Drill Sharpener. Another comment gave a link to another source and included a photo. I am always cautious about links to products, lest it appear I have a commercial interest and am advertising a product.

[dogshan]

A great tip, small bits are difficult to sharpen. Thanks

[Bardouv]

"One broke for me once and went through my thumbnail and out the other side of my thumb. " Any pics???

[Phil B]

It was back in the early 1980's, so there are no digital pictures. I did not take any on film, either. I was one of the first patients a new doctor had. He admitted he had never seen anything like it, but it healed up well. I put facial tissue over the bloody, broken thumbnail, but was still noticing blood dripping on things. It was then that I looked on the bottom side of my thumb and discovered a hole there, too. My initial reaction was such a surprised one that I pulled the drill bit back out before I knew what had happened.

[thepelton]

Eeew!

[Phil B]

Yes, eew! It sounds worse than it was. The bit was only a 1/8 inch bit, so the hole was not real big and pretty much closed itself right away, except for a little blood dripping. As I remember, it throbbed a bit for a little while. There was a numb section along the top of my thumb for more than ten years, but the nerve tissue finally connected again and it has been normal for a long time. For a few weeks I painted the broken sections of fingernail with clear fingernail polish to keep from snagging rough edges on things. Finally the broken sections grew out to the end of the fingernail.

[thepelton]

Just remember, all you wannabe cabinetmakers, anything that can cut Oak can also cut flesh and bone!

[Phil B]

I think about that every time I see a butcher cutting meat (and bone) with a bandsaw that is not much different from the bandsaw I have in my workshop.

[chalky]

My granddad used to be 'mustard' at sharpening them by eye but i don't seem to have inherited the drill sharpening gene lol great 'ibble' by the way:) there's nothing better(and safer)then a sharp drill bit! Ive actually used drill bit's that have been re-cut that seem sharper than when they were brand new?lol

[thepelton]

Chalky is right. The sharper your drill bit is, the less chance of it "walking" off the material to be drilled, and the less chance of it jamming halfway through.

[Phil B]

Thanks. I have heard of people who buy a cutting tool and then sharpen it themselves before using it. I also once heard of a man who bought a piece of farm machinery, but before using it he cut through all of the welds and did again them himself.

[Mikey D]

Very good information PB! I was lucky enough to work in a machine shop while I was in high school (aproximately one billion years ago) and my foreman taught me how to do it by hand. By hand the key is to get both cutting edges the same size and height so they will both cut and the hole will be the proper size. I like the gauge in you 'ible as it would make it a bit easier to resharpen a broken drill. I am in total agreement with your reply to several commenters. It takes quite a bit of practice to be able to sharpen a drill by hand. Most anyone can make a drill sharp, but it is difficult to make it drill the right size hole and last a long time. Once again... . ...good work!

[billdan]

Anything is better than a Drill Doctor. They don't stay in adjustment and are slower than using the manual jig. The DD will eat your bits. It is not worth the money. It would be cheaper to throw out the dull bits and buy new bits, unless your a daily user.

[Phil B]

Yours is an interesting comment. I have not used a Drill Doctor and just assumed they are the ultimate in home bit sharpening. I like the jig shown in this Instructable. It does a good job when the set up is done properly. It is also relatively inexpensive.

[Phil B]

Thanks. I may get the nomenclature wrong, but I think the trailing edge of each half of a drill bit is the heel. I may get the leading edge sharp by hand, but the heel is often way too high and may even meet the steel I am drilling before the leading edge. Not good. In my mind I know how it should work, but my hands have not been so good about following instructions. So, I rely on this sharpening jig.

[kwkstar]

Ditto .......... I'm a toolmaker!

[Phil B]

Thanks. I searched Instructables before posting this 'ible and was surprised that no one had posted anything about sharpening drill bits. Congratulations on learning to sharpen bits well by hand. The literature that came with my sharpening jig says this process is suitable for home users, but not for industrial and machine shop applications. But, I have always been pleased with the performance of the bits I sharpened. The do not wander and give me a good round hole of the proper size. (I am a home user.)

[berserk]

Hey Phil, Great Instructible! I bought one of these holders some time ago but was having limited success. It only came with one page of picture instructions and didn't mention angles or directions of movement. Your explanation adds a LOT to that. I also like your trick for the smaller bits - I have tried to do them by hand with a dremel, but with limited success. Mind you, even if the angles are not perfect, it is often still a heck of a lot better than a blunt bit! Two questions, though, for clarification. In step 5 you say "just a tiny bit less than the radius of the bit ". On the picture you indicate what would be the length of one edge. This would be longer than the radius of a hole drilled by the drill. I am not so familiar with the lingo re. drills, but is the radius of a drill measured along the edge? Also, do you mean "just a little bit less than the length of one edge" or "...than half the diameter of the drill"? In step 11 I have a hard time figuring out what is going on. Could you add some pictures from different angles? Maybe I need to dig out my own tool to see what you mean... You say you are using a radial arm saw for your grinding. That is an interesting idea. I don't have a bench grinder. I was thinking about using my belt sander instead. Do you think that would work? What grain do you use on your sanding wheel, and do you think it makes a difference? Thanks for the good work! T

[Phil B]

For all who are interested, I added some extra photos related to the original step 11 and made a change in the photo for step 5.

[buckshot00]

http://www.drillgadget.com

http://www.youtube.com/watch?v=2jUvRnyQHzw

sharpen up to 1/2 inch bit and it costs 6.95!

[Phil B]

If you look closely, the Drill Gadget works on the same principle as the bevelled wooden block near the end of my Instructable.

[buckshot00]

http://www.drillgadget.com/

Works awesome cheap. There is also a video on youtube. I love mine!

[caitlinsdad]

Very good. Too bad all most of the drill bits I have are the splitpoint TIN coated ones that promise to stay sharper longer... They still go dull when used a lot to drill holes into drywall for fasteners. And I get a lot of use out of my stepped pocket-hole drill bit. More complex shapes that I usually have to resort to buying another one when needed. The full featured Drill Doctor is expensive though.

[Phil B]

I have one brad point bit in my entire collection of drill bits and have not used it much. I do not know what a person is supposed to do with specialized profile bits like you describe. Perhaps several friends with similar needs could go together to buy a very good Drill Doctor and then pass it around as needed. That has some problems, too, though.

[berserk]

A sharp brad point bit can do a much nicer job in soft woods than a plain drill bit. It slices the circumference first , so there are no crushed fibres.

[kwkstar]

This is the right way to sharpen a drill bit for an inexperienced person. But after a while you can do away with the guides if you sharpen enough drill bits. I am a toolmaker the people at the shop bring the drill bits to me when they mess up with the auto sharpeners. I have a drill doctor I don't use it because it is faster to sharpen it by hand and I can split the point by hand. And my drills drill true..

[berserk]

Any hints for us, kwkstar? Aside from becoming a professional tool maker, I mean? Often there is some technique to these things... you try it and can't make it work, until someone tells you the trick. Doing a http://en.wikipedia.org/wiki/Track_stand was like that for me...

[Phil B]

I admire your ability to sharpen bits well by hand. I sharpen bits very infrequently and would not get enough practice to do the job well by hand. Part of the reason why I do it so infrequently is that someone gave me a box of old bits many years ago. Most are in the sizes I often use. I sharpened them all at the time. When a bit goes dull, I often grab a sharp one from that box and use it. Thanks for your comment.

[mortso]

You can get these Drill Angle adjusters at Sears, and Harbor Freight has one too. They Rock! Thanks for sharing the post.

[roncar]

Lowe's and Home Depot are running specials on the Drill Doctor XPK . I just bought one for about $75.00/ Seems to work good with a small learning curve but the DVD explains and demonstrates the basics.

[jongscx]

I don't have an bench grinder though :-( I may just have to spring for the drill doctor, unless there's a dremel attachment...

[hirenpanchal47]

Complicated .......! but nice ....

[michaeldeb]

any idea about a device to sharpen spade bits? My twist bits seem to hold their edge for a long time but the spade bits go quickly.

[Phil B]

You can use a file or the flat side of a fine stone to sharpen the individual cutting edges. Some careful work with a Dremel would do the job, too.

[pfred2]

I have one of these sharpeners and made a base for it so the grinds would be perpendicular to the lip edge of the bit. You may see it on the left in this picture. Hope this picture thing works!

[nibbler125]

i just freehand it and im not half bad at it. at my school we have a box full of dull bits so i get in lots of practice

[Phil B]

You may also have some natural ability that helps you do a better than average job at sharpening bits by hand.

[bennydo]

It is a human thing to have an opinion! Everyone loves to comment especially on the web as it is so easy to do, irrespective of ones understanding on the topic. I have noticed some people carelessly playing down on the methods to repair simpler things we take for granted like $2 nail clippers or sharp drill bits straight out of the packet etc... And I can bet the comments either come from children who think they know everything or adults who still do! To the people that clearly know everything, were you naturally gifted or did u pick bits up along the way to get to where you are today? And to all the others... one little hand skill or concept leads to another and another... learn as much as you can. They all build on a bigger picture. I would not know a thing in this life if it was not for the kind people that took the time out to show me how. If you look at everything you do, it’s made up of all the people and lessons that you have learnt along the way. Even careless comments are an example of that. Phill, Thank you for taking the time for the benefit of all the rest of us!

[thebluebulk]

that right! i found this VERY helpful. its probably a lot better than holding the bits by hand to sharpen! hehehe :-)

[Phil B]

Thank you. Part of the fun of sharing something at Instructables is that I can download a PDF of it and have it for future reference or to show someone else later.

[mod-ern man]

You're so right about the Drill Doctor. I have one & the "chuck" used to position the drill bits for sharpening don't hold the bit properly without a lot of fiddling. I'm going back to the using the same holder you show. Takes a minute or two to set up, but then you get much better results on all size bits.

[Phil B]

That is interesting. Thanks for the information.

[rockndb]

Keep your eyes peeled at estate sales. I got an electric B&D one for a dollar.

[Phil B]

I remember seeing those in stores when they were new. How well do they work? If I remember, they have a grinding wheel in the bottom of the unit with a raised portion that includes a bevel upward. I always wondered if that stone would need replacing.

[rockndb]

Phil, I love it. It has a thumb wheel that lets you adjust relief for the perfect cut. I'm pretty sure(but not positive) that the stone that the grinding wheel is made out of is as hard as, harder than, or close to as hard as the metal the drill bits are made of. Therefore minimal wear on the stone occurs.This sharpener is well over 20 years old and the wheel is actually not very worn. -Dan

[Phil B]

I think I saw those in stores during the early 1970s. I think they retailed for around $30 then. Thanks for the information.

[rockndb]

Happy to pass some knowledge on to fellow grease monkeys.

[rimar2000]

Thanks, Phil, this it very useful. I sharp my drill bits by hand, but sometimes I ruin them.

[Phil B]

Rimar, I expect you can buy this tool in Argentina. Am I correct? It has been available in the USA during probably the last 40 years. I admire you for making an attempt at sharpening your bits by hand. I have thought a person might be able to make one of these tools. The pivot post on which the tool swivels has a forward caster angle of about 3 or so degrees. That gives a slope behind the leading edge of the bit. Thanks.

[Phil B]

Correction: The caster angle is more like 7 degrees.

[mynameisjonas]

what was the name of the sharpening tool again?

[Phil B]

Mine was sold by Sears under the name of Drill Bit Grinding Attachment. Amazon has it as a Grizzly Drill Sharpener.

[mynameisjonas]

thanks!

[tercero]

I bought a similar tool at Princess Auto (like Harbor Freight in the U.S.) here in Canada. Chinese made hunk of junk but it does the exact same job and I paid around $15 for it on sale.

[Phil B]

I do not know what you have. Back when I bought mine from Sears there were discount stores that had a cheaper version of lesser design. I never tried one of those, though. I have not seen those for a long while.

[uguy]

Excellent ible, you've saved many drill bits with it. Thanks for sharing.

[Phil B]

Thanks. I wish I had learned how to sharpen bits by hand and could give a reliable Instructable on how to do that. Still, I expect there are plenty of people with a small box full of dull bits and they simply buy new bits when one is too dull. If you can sharpen bits, you may also find a sudden new popularity among your friends with dull bits.

[SinAmos]

Very useful. Thanks, but I just bought a new titanium set, so I should be good for a while.:)

[Phil B]

Enjoy your new bits. Somehow I seem to use certain sizes more than others, and sooner or later a bit will need sharpening. Then the question becomes whether to ignore the dull bit, replace it with a new bit, or sharpen it. I suppose the ideal solution would be to find a friend who owns a Drill Doctor and who will sharpen your bits for you. Thanks for the comment.