Could someone please recommend a link or procedure or method to help me sharpen some drill bits?
Do I need one of those jigs that you see on eBay or a Drill Doctor (or whatever it is called) or just eyeball it on the bench grinder?
Any and all help would be appreciated.
Thanks a lot.
You can do it by eyeball on a bench grinder. It will take some practice. You have to make sure your cutting edge stands a shade higher than the rest of the flute. If it doesn't it won't cut.
Why don't you google "sharpening drill bits" and see what you find.
When it comes to sharpening drill bits you either have or you don't.
It's worse than "welders".....even a lousy welder can get something to stick.......but a drill bit that's been all screwed up isn't going anywhere.
I never needed or used one but I have heard the Drill Doctor IS something that actually works.
I do it on the bench grinder like Ted. But for the little ones a small Dremel-type grinder is handy.
It is a crap shot most of the time,but a few years ago ,I bought a Drill Dr. I like it as it usually does a good job.
I bought a drill doctor a few years ago. I have been very happy with it. One tip, if you get one, do not over tighten the chuck when setting the drill bits.
Youtube is a great resource for "how to" videos. It's the first place I go to when I want to learn something new, especially maintenance and repair.
Here are some videos on sharpening drill bits on a bench grinder:
Here is a general search for drill bit sharpening:
http://www.youtube.com/results?search_query=sharpening+drill+bits&oq=sharpening+ drill+bits&gs_l=youtube.3..0l2.1425.5062.0.58184.108.40.206.220.127.116.114.871.5j2j0j1.8. 0...0.0...1ac.1.rP9U23lC78o
Grinding it by hand can be tricky and takes some practice.
My best advice is get a fairly large drill, over 1/2" is best, and be sure it hasn't been sharpened before. In other words, it should have a proper "factory" grind on it yet. Ink up the tip with a magic marker and begin grinding it very lightly, trying to duplicate the original grind in shape and angle. The inking should help guide you in knowing where you've ground, and where you're lacking contact. Basically, you begin at the cutting edge and, as you rotate the drill, also swing the shank end of the drill downwards to make the grinding wheel sort of roll off the drill tip, from the cutting edge on down. Your large practice drill should teach you the basic motions. Be careful to grind equal amounts off each side and to maintain the tip angle.
I agree with Craig about drill bit sharpening.
Its true that some guys have a real knack in sharpening bits just as in welding. I think its takes practice and some can get the knack quicker than others BUT you can learn if you practice to get the angles right.
As others may chime in on this you can get a new drill bit and take some others to use for practice in getting the correct angle that the new one has.
I remember in the machine shop class I took years ago we were given a box of old discarded bit to sharpen.
We were told the correct angle and given a good bit to use to look at and to use as a guide.
I got pretty good and as the instructer said its takes practice.
Same thing with welding and any other skill.
It takes practice and practice and more for others and less for others but you can do it IF YOU PRACTICE.
I used one of the drill bit sharpening guides and soon found that I could do it as good as the guide.
Jerry's pretty much described the procedure better than I could. I do sharpen bits on a mild or fine grinding wheel and was shown how years ago by an Old Timer at work. I am now older than the old timer as he stopped getting older a few years ago. That roll off he describes is important.
Joseph the highest point of the grind HAS to be the cutting edge. Everything behind it has to have "clearance" the angle is not critical. It's not really critical that both sides be the same angle or be exactly ground the same length. A good eyeballing will work. However ur drills will cut oversize be aware of that.
Get a cheap steel protractor or drill gauge. I like a protractor
So you can vary ur angles. Think clearance more than anything. Keep in mind they will likely drill oversize so drill ream when critical. There is an easy way to do it were you basically just grind two flats and don't have to roll the drill. It's ugly and don't hold up but will cut
I bought a top of the line Drill Doctor last year. It has been an excellent investment. I spent a few days sharpening a box full of old dull bits. It works great and doesn't take guess work to get the angles right. Save yourself a lot of aggravation. Spend a little money on a quality, made in USA tool that will keep your bits sharp for many years to come. Get a Drill Doctor.
I agree with Steve. My Drill Doctor cost a hundred dollars and does a great job. As often as I break the ends off bits, it doesn't take long to add up to a hundred bucks. I know that it's possible to grind them by hand and by eye, but I haven't had much luck with that. If you want to spend the time it takes to get good at that, power to you. But for us who would rather spend our time doing other things, the machine is money well-spent.
I agree with those who advocate for Drill Doctor. Seems to me most who read these posts already have their minds made up and we who respond mostly do it for ourselves. For every one person who wants help there are a bazillion of us experts who advocate for a particular point of view. As my Dad used to say "too few Indians, too many chiefs."
I could not figure it out, wasted allot of time trying. Also my eye's are not what they once were. Got the drill Doctor and have been pleased with it, works for me.
I have an old B&D I've never used. Is it worthwhile?
Black & Decker....???
Using a new drill for a pattern or a guide is a good idea, IF, the new drill is sharpened correctly. A guy I used to work for got a great deal on some Chinese Silver and Deming style gold colored bits several years ago. Every one of them were ground with the angle backward, in other words, the cutting edge was higher(as chucked up in a drill press)then the surface behind it. I had to resharpen the whole set. Dave
Yes, Harold, Black & Decker sharpener. Sorry.
Buy yourself a previously owned Drill Doctor on eBay. It woks beautifully, using a fine diamond drum.
If all you drill is holes for wood projects, then you can learn how to sharpen drills on a grinder, but nobody can sharpen a drill by hand for precision machine work. The reason is the hole it drills will always be slightly larger than expected. One cutter on the drill-face will be longer than the other, no matter how carefully or skillfully you grind it.
The master machinist from whom I learned the art taught me how to make a hole 0.002 larger than the drill. Go to the grinder and take 0.001 off one cutter, shifting the pilot over to the side.
One of these will make life much easy
It sounds like the drill doctor is the way to go. I've always sharpened freehand. There is actually a little gauge (normally spelled "gage")that can be used as a guide for sharpening. I used one for a couple years when I was going to school for tool and die and used it for another couple years afterwards. We built the dies to punch them in school on the punch press. I lost mine several years ago but I'm able to sharpen bits now without one. The gauge had marks on it. You were able to check the leading edge angle and the back grind for clearance. It also helped keep the grinds on center to the drill. Good luck.
Or just go buy a Drill Doctor. But when you're drilling something at someone else's shop and you're trying to get by with a dull drill freehand grinding is a good thing to know.
I think the primary emphasis is getting a worn drill to cut. If its a precision application you should use a ream or at least "drill ream" the hole.
Joseph do you not kno any machinist's in your area? They could show you.
By all means a drill doctor is worth having.
I don't think Joseph is worried about a precision application. It sounds like his goal is to sharpen dull drills. I don't think he's building jigs, fixtures or dies. I still think the drill doctor is a great idea. :-)
I use my Drill Doctor when I have several bits to sharpen. I also use my 8" bench grinder with a diamond wheel to sharpen a bit if I need it in a hurry. The diamond wheel (Wood River brand) is expensive and used daily to sharpen my lathe tools. Does a great job.
I recently found the 3/4 inch jig on a discount table for almost nothing.
Here's what I use. Not at all cheap but I bought one used off eBay sometime back for a fraction of the cost, (but still pricey).
Nice machine Jerry!
To add an extra note to everyone's great suggestions:
If you are sharpening drills that have been done a few times already, you may find it necessary to also "thin the web" on your drill as well.The web of a drill is the solid centre of the drill's core material and it gets progressively thicker towards the shank or rear of the drill.
The procedure for doing this is to carefully grind out each flute with some slight contact to the cutting edge centre,equal on each side.This will relieve the little straight "edge" created as the web gets thicker.The more point you have and less edge,the easier your drill will cut.
A little bit of edge is ok,too much and your drill will perform poorly.
I think more often than not,I explain things poorly,so if you google "thinning drill bit webs",I'm sure you will find a better explanation than mine,as this is an important aspect of drill sharpening,especially with drills over 3/8" diameter.
Darren I thought you did a good job of explaining it. Thinning the web is very important. I know people probably think it's foolish for me to say but I consider my drills as perishable tooling. Mostly because everybody that uses their tools will have to purchase new ones. One of my not so impressive facts is that I also consider my screwdrivers as perishable too. I'm not proud of it but I use them for more then just screws.
Ya Mike, I find myself grinding screw drivers all the time for specific screws, straight slot ofcourse. I'm sure many others do it too.
Darren, definitely glad u mentioned web thining.
One of my first drill bit grinding devices was a sold by (not made by) Snap-On DG30.
The unit is designed to be clamped to the grinders cast iron wheel guard in place of the
tool rest, and should be used with a plate back style (cup) grinding wheel.
The drill bit is indexed in the clamp, and it’s micrometer feed is calibrated in thousands,
enabling accurate grinding of both cutting edges. The bit must be rotated in the clamp
and the feed backed off to grind the second edge, making it slower to use than the Drill
Doctor. It’s adjustable to any angle and the relief is automatically ground by it’s cam action.
The lower left hand lever swings the tool away from the wheel, but can also be used
to true the wheel face when a diamond wheel dresser is clamped at an appropriate angle
in the drill bit holder.
Works well but slow, so mostly used for bits used in the lathe when precision hole is desired.
Here is a photo of mine, that I purchased from a military surplus (marked ‘RCAF’) and a scan
of the 1961 Snap-On catalog page, when it was about Can $50.00.
It was discontinued shortly after.
The DG-825 on the right is still available under numerous brand names (some import)
but would not be my choice. It does work, but is very shaky or flexible.
I have a number of different types of drill sharpeners, but although not perfect (but ok once one learns to use it)
my earlier ¾” Drill Doctor with the split point feature gets the most use.
Well its my turn to yak. Sharpening a drill is easy once you get the hang of it. All drills will drill a little over size. Thats because the cutting edges have to be the exact length to make a proper hole. But if you drill a SMALL pilot hole first the larger drill will make the proper size because point is no longer guiding the drill. Scott
I’m having a little trouble with your theory Robert.
Will the ‘V’ point on the end of the drill bit not center
in the pilot hole, leaving the bit’s longer cutting edge to
dictate the finished hole size? (sort of like a fly cutter)
Okay, my advice. (Just couldn't keep my trap shut any longer.)
IF you are over 25 years old, OR you are not mechanically self driven, AND you have not already learned how to sharpen drill bits on a bench grinder yourself. Then you should probably buy a drill bit sharpening tool/jig.
I have always been mechanically self driven, and was taught how to sharpen bits when I was about ten. My eyesight is not as good as it used to be. Bits under 5/32 I still do, totally by feel. Everything else I do just as I always have.
If a person is used to doing something like this, it is so easy that it is difficult to understand why anyone could have trouble with it. I have talked to and worked with so many people that use something like a Drill Doctor. They seem to love it, and cannot understand how I just walk over to the grinder and do it myself. Those tools/jigs seem to work well, although I have never used one (I have one, somewhere, never used it).
Others, previously, have given good explanations of how a bit needs to be sharpened. If you haven't already learned to do it, but think you can, TRY IT! What have you got to lose by trying several bits? You might save the cost of buying the thing. Otherwise, a bit sharpening tool will just have to pay for itself eventually, which it probably will.
The one I have looks something like what Art Bell showed.
Drive carefully, and enjoy the holidays! W2
Sears used to make a sharpening jig to use on a grinder. A place I worked had a bench grinder and I mounted it to the bench at the grinder. I needed sharp bits as I had to quite a bit of drilling in the repairs. Had to furnish my own bits also so I tried to keep them sharp. The jig was not expensive and did a good job. They may still stock them.
Oil stones work for me.
Art, The sides are now the guide as the point is cutting air. It can not move the drill around so the cutting flanks are the same length. Scott
Robert your theory works up to a point. If you can go slow enough to get a heavier bit to act as a flycutter and not flex then you'll be in good shape. But don't feed to slow or you'll burn the tip up on your drill. If you feed it any faster to keep it from burning there's a pretty good chance your drill is going to flex. Now before you say you have to use oil or some kind of coolant on the bit keep in mind this is the 21st century. Most people don't know what coolant means and they don't have time to do things at a slow pace. So what they're going to do is drill the hole with the smaller guide drill, dry of course, and then jam the larger drill through the hole to get it to size. There's one more thing to keep in mind. If you need the hole to be closer in tolerance than common "B" size tolerances then drill with a new drill and ream the hole to size.
I dug out a new (never used or sharpened) 1960’s vintage ½” drill bit made by Steyr
in Austria and sold by Snap-On, just so I would have a good quality bit for the test.
Using the Drill Doctor, I sharpened one lip on the bit once, and then the other lip twice.
As usual, I could not find my drill gauge so did not measure the offset but it was very obvious.
I have offset bits before but never to this extreme, but I wanted the results to be clearly visible, not just a few thousands.
Drilled the holes, took some photos, put the camera card into the computer card slot -
AND - Zap! or was that Zolt? - Anyway my computer made a crackling sound gave out some magic smoke and died!.
Diagnosed it today and found the power supply had two blown electrolytic capacitors.
Dug out a spare power supply, swapped it out and can now post the results of putting my theory to the test.
The major difference between pilot hole and no pilot hole was the drilling effort required.
I was tempted to split point the bit for the test, but did not want to influence the outcome.
The cutting angle and relief were the same on both lip profiles on the bit, only the lip length was different.
Both holes were drilled with the work piece held firmly in a vise clamped firmly to the drill press table.
Nothing moved, and I purposely stopped the ‘no pilot’ hole version before it broke thru, to show there was indeed no pilot hole.
You can see the I/D of the hole cut by each lip, with the depth of the ridge being the height difference of the drill bit lip at the o/d of the bit.
(As a side note or observation, it seems if the material was thinner than the height of the short lip, and you stopped drilling precisely when the short lip broke thru, the hole would have still been ½“ I/D.)
Mike G, Most people today don't understand that there is such a thing as drilling a precise hole in anything other than in nano technology (which they think the world revolves around). Me? From 1/16 through 1/2 inch, I have a complete numbered and lettered set as well as almost everything by inch incremental by 1/32s and many by 1/64s. The number and letter sets I only use when precision is needed. That way they don't get worn or broken and I not have them when I do need them. I also have a few special sizes for electronics. Within that range, I probably have less than half the sizes available.
Most people today have no clue about the world around them.
Drive carefully, and enjoy the holidays! W2
(This may need translating to English)
When I ponder the subject a little more, it becomes apparent
that your theory is correct if the thickness of the material is
less than the vertical height of the lip on the ‘short’ side of the bit.
Once the your bit drills thru the pilot hole it no longer centers the
bit. The over size of the hole will be the size it was enlarged to
when the material’s thickness lets the ‘longer’ lip break thru.
The hole will always be the full over size if the material is thicker
than the height of the longer lip.
Hi Wayne – While it’s nice to have a good selection of drill bits,
it’s also nice to know the pitfalls involved with sharpening them.
And understanding how to customize or tweak the size if and when
the need arises can be of help when that rare occasion occurs.
My chance to go nano tech was lost when my #80 run away with half of
my #72 never to be seen again. (I think they are hiding under my bench).
For Sale: #72 and #80 drill bit. $76.32 each. (The $0.32 is for tax) :-)
Ph: Wayne Sheldon, Grass Valley, CA.
That price is just as scary as looking under my bench <@^@>
He's not cheap, but he can be had.
Well, two things. In looking in YouTube,these are the two best videos I've found so far on how to hand sharpen drill bits:
sharpen drill bits 01
sharpen drill bits 02
And Santa stopped by early and left me a Drill Doctor 750X...I'm looking forward to trying that out over the holidays.
Thanks to all for the suggestions and ideas.
It's good to be a christian.
Hi Guys, Does anyone use a Tormek grinding system with the drill grinding attachment? I have a Torkmek T7 wet grinding setup to do my wood lathe chisels & knives for planers & joiners. Works very well. Just wondering how well the drill attachment jig does before I spend the megabucks for one. Thanks, Dennis