Thread: Hand Sharpening Drill Bits

Dean, I am sure that I speak for everyone on this forum in wishing all the very best for your wife and yourself, in this coming battle. You will both be under great stress and strain, and I know that we all hope for a speedy and successful recovery, and that you get all the support and care that you could wish for. It is good that it has been discovered in the early stages, as with most diseases, an early diagnosis, is perhaps the best weapon against the disease.
I am sure that a "late pass" can be granted for your Drill sharpening Class using a drill sharpening fixture, but we will be waiting when all has settled down at your place and you are both fully recovered.
Kind Regards,
Rob

I wrote a full length article on drill sharpening that was very easy to understand. If you do a search you will find it here on this forum and also on the land yacht forum. I have taught many people how to master the (Black) art of drill sharpening and have never lost a student of any age. The secret to sharpening a drill is to fully understand the geometry of the drill and how they actually cut. If I can help out with passing on the technique and knowledge of sharpening these things, please let me know. The required angles that form the "cutting end" are all different depending on the material that you want to drill. I have drilled many a hole in sheet brass shim with no problem and also in many plastics and stainless steel. Brass is another matter altogether but it's very easy to sharpen the drills for this awkward metal. Let me know if I can help out.

I have a book called "Drills, Taps and Dies" by Tubal Cain which is part of the Argus Workshop series that has a lot of information about bits in it that I have found very useful. However, I found the section (3) on drill bit sharpening like most articles doesn't just really give enough detail and all it really says about the "how to do it" is practice. It's still a useful book though and there is/was a PDF version floating around on the web.

Originally Posted by Kody

I wrote a full length article on drill sharpening that was very easy to understand. If you do a search you will find it here on this forum and also on the land yacht forum. . . . . . Let me know if I can help out.

Is this the article?
How to sharpen a drill - Land Yacht Sailing Construction - Seabreeze Forums! If so it would be useful to have it in one PDF rather spread across several posts as it does seem to provide a bit more info on the "how" than the "just practice" suggestions in the Cain Book.

While a text (even with pictures) based article is useful for learning a skill like drill bit sharpening, after reading a heap of articles and trying to sharpen I found I wasn't even close (I'm still not that good) until someone actually showed me, and then let me try, and then corrected my mistakes. Yeah I know - I'm a pretty dumb student.

One thing that I think would be really useful is maybe short videos that show "how to do it" - and also "how not to do it", and "common mistakes made" by newbies. Some macro video footage of properly and poorly sharpened bits, ie rotating the bits so they can be seen from a number of different angles would be a bit more useful than just flat 2D images.

Yeah - a lot of work I know.

Just read Kody's article on sharpening which is terrific, thank you Kody.
Now, I have had a set of drills for quite sometime now and just replace the broken/ lost ones (the ones mistakenly put into their nail pockets) ;(
My question is, which reputable shop sells a good set of HSS metric drills ranging from 2mm to 13mm in a boxed set.
The yum cha brands that the tools shops sell are questionable even though they state they are HSS, one has to wonder.
Cheers

I just like to say at the start of this tutorial is not intended to teach the grannies how to suck eggs but help those of us who use drills for all those mundane tasks how to do this relatively simple task.

Without wishing to get into a bun fight I had been taught that a drill makes a hole and if you want a round hole to the specific dimension bore it or ream it. I'm not a fitter,machinist or toolmaker by trade but a boilermaker background. I welcome any assistance I can get on refining any points.

For years I have been amused by by those across the pond who impress us with stories of the marvelous things they can do with their machines but then turn to the most common of all workshop tasks- sharpening and drag out the Darex or Drill Doctor which cost multiple times that of the good local set of HSS drill sets. There,s probably a place for the drill sharpening jigs and tool but most of us,I contend don't need one.

Like some of the other correspondents I have vision and arthritis problems which limits me somewhat in the small sizes -I too don't bother with sub 3mm sizes unless I am in a pinch and don't have an immediate replacement.

Safety

As with any lesson safety is paramount and our grinders have the capacity to injure us if we allow certain circumstances to develop.

Gap
Gap between tool plate and wheel - 3mm minimum.That gap can still grab say a glove and the possibility of having a finger half ground off in an entrapped glove is a good reason not to wear gloves while off hand grinding of any sort.

Rated wheel speed
Simply that the wheel speed on the blotter is rated to the tag on the grinder machine.

Wheel condition
A good surface condition flat level free of cracks and impacted metal. If you are a teacher its not uncommon to find the grinder wheel on a weekly check that's been ground with aluminum. Unless you have kids I would not think this would be a problem,but thought I would chuck it in anyway.

Both the above faults can cause the wheel to explode like a hand grenade. . I was taught to start the wheel and step back for a few moments as this is the most likely time for such a failure and its something I still do to this day, 40 yrs later.

So that out of the way unless there's something highly unsafe that's been omitted ,I start staking pics and get this show on the road

Grahame

Grahame just a couple of things,the Gap you refer to seems a bit large,all tool rests that I have re-set after dressing are set as close to the wheel as possable,this is for 4" through to 15" wheels.
If this is to be an idiots guide to drill sharpening let them know that the wheel should be dressed as you stated to make sure the face of the grinding wheel is flat.
Maybe even to the extent of having a dedicated wheel just for Sharpening.
Might also be good to mention that the Ridgidity of the Tool rest can play a big part in the ease of grinding the Drill.
Also that the Grinder should have sufficent power to Grind the drill,some of those little cheaper ones with less than 500watts may struggle.
You may even have to delve slightly into the Grit size of the wheel,even though most wheels can be used some perform better.
Also let them know that there will be no detremental effect to the drill if they dip it into water to cool during sharpening.
Maybe even cover the types of Wheel Dresser available and there use.
Also good to have a good light source available.
Maybe a protactor or grinding gauge,or how to make a simple version for home use.
And of course Eye protection.

Originally Posted by Kody

I wrote a full length article on drill sharpening that was very easy to understand. If you do a search you will find it here on this forum and also on the land yacht forum. I have taught many people how to master the (Black) art of drill sharpening and have never lost a student of any age. The secret to sharpening a drill is to fully understand the geometry of the drill and how they actually cut.

No, the secret to sharpening drill bits is to transfer that knowledge to movements of the hand which unfortunately requires secondary computation inside the brain of the person doing the learning. Big difference. Personally I don't want to. I am only interested in drilling the hole that I have to sharpen the bit for.

I don't wish to put people down but to maintain a precise angle and length on both cutting facets of a twist drill requires a lot of skill and practice. If you are not doing it all the time this becomes a problem. I generally have a sharpening bee after saving up blunt drills for a while.

Many years ago I worked for an engineering firm that had machines to drill rocker shafts for sigma astron motors. We put out 450 finished shafts a day at one point. These machines had a drill for every hole, which in one was about 12 including oil and bolt holes. Not all were all the way thru. The bolt holes were thru both sides.

There were two toolmakers who had the job of sharpening drills. They used a machine bought for the purpose. Some of the drills had a profile like a centre drill with the centre up to 12mm long and they were made up on this machine. Need the machine for these. All the drills were sharpened on this machine however.

These guys could sharpen a drill by hand with eyes closed just about. They mostly did with other drills. If you do it all the time you remain profficient. Having said that I have made a note of your post which was linked in another post here and I will be reading it and I will have a go. Sometimes I want to touch up a drill to finish a job and have largely lost this ability.

Dean

Originally Posted by Ropetangler

Dean, I am sure that I speak for everyone on this forum in wishing all the very best for your wife and yourself, in this coming battle. You will both be under great stress and strain, and I know that we all hope for a speedy and successful recovery, and that you get all the support and care that you could wish for. It is good that it has been discovered in the early stages, as with most diseases, an early diagnosis, is perhaps the best weapon against the disease.
I am sure that a "late pass" can be granted for your Drill sharpening Class using a drill sharpening fixture, but we will be waiting when all has settled down at your place and you are both fully recovered.
Kind Regards,
Rob

Thankyou. Many years ago I tried looking into newsgroup forums for information on my interests at the time. All I read was bitching. From start to finish it was a total put down and no information at all.

I was delighted to find that the community behind this forum is based on support and knowledge. I am learning a huge amount and I hope to be able to assist others in return.

Dean

Pipeclay,
The gap is what I have always set as boilermaker ,so I will acknowledge ignorance on that measure.I cant do any harm to have it closer.
As is for you a flat surface on the wheel face is important for me.
In our shop I organized a dedicated wheel for HSS tooling and drills as those that don't care too much leave various grooves and hollows in the wheels not conducive to good sharpening of nay sort. I shall address wheel dressing for without that there's no proper sharpening that can occur.

Funny you should mention the term Sharpening for idiots .

While I would never think of any of our forum members being idiots ,I am guilty of thinking in this fashion about some of my own students.

After showing some individuals numerous times,the procedures re drill centers, I created a power point entitled Center Drills for Dummies taken from the advertising site where you can make up a ............ for dummies cover page.

What I hope to do on these pages ,is to capture those visuals of the hand manipulation for the turn and dip technique. via suitable photos.

As far as the tool rest rigidity goes, I too found that even on the 200mm models most of the tool rest were mostly pressed metal junk and quickly replaced them with 6mm plate.

For the wheel grits I chased up the grit sizes for roughing and finish grinding.I cannot think what they are right now but shall include that.

For lighting, my home machine has a flexible shaft with a 100 watt equivalent white twisty eco thingy globe stuck in the end. Its different at school as the monkeys can't help interfering with any light fixture and quickly the adjustable bits are no longer that.
It was easier to set it up near the door and use the ambient light.

.
Grahame

Hi everyone

Best wishes to your wife Dean.

Dean, I am with you in that I use a drill grinding jig, and look forward to your future notes.
I like the repeatability of reasonable accuracy of drills ground in a jig.

For interest, I modified my "Craftsman" guide.
I replaced the square section with 300mm of 8 x 8 mm key steel, secured with a small screw on the forward body, so as to make this and the original bars interchangeable.
This was to enable grinding long shank drills up to 300mm long.
I added a small screw at the end of the square secrion to stop the screw adjusting unit from sliding off the end.
I removed the original sheet steel alignment Lip Rest "thing" at the grinding end of the main body, and just use a visual setup.
I made up several "trays" of various lengths from 20 x 20 thin aluminium angle, so as to hold the drill body centralised more, and to stop the drill top hold down clamp from misaligning the drill when tightened. I filed down two sides of the small metal square which is welded onto the longtitudinal adjusting screw, so as to allow the trays to slide under the square end, and to the edge of the moving casting.
I made up an extra clamp to hold down the shank end of the drill in the tray and guide, so as to improve drill axis alignment during grinding.
I added an extra screw to secure the guide at a grind angle of 59 deg, to back up the wingnut.

I use my jig bolted onto the table of a drill press, and use a slow grinding wheel on a mount in the drill chuck.
This utilises the side of the wheel, and so grinds the drill face concentically with the drill axis, similar to your setup. Thanks for your highlighting this important aspect as well.

The instruction sheets for the various guides of this generic type are a bit confusing.

I find that drill "overhang" past the end is critical for grind back angle and relief, varies with drill diameter, and I now carry out a visual check with an untouched new drill, swinging it to test and optimise the overhang for various drill sizes.

I had the time to learn how to use this guide, and it paid off for me.

I agree with you comments about this forum; very supportive, with lots of experienced people watching and helping.

cheerio, mike

Grahame,
Your post says "Gap - 3mm minimum" I assume you mean maximum?
Stuart

Grahame the term should probably been Dummies just didnt think of it.
What I was trying to relay in that reply is you will have to treat everyone as if they have no knowledge what so ever.
I have normally found when trying to train or teach that there are sometimes things that you think everyone knows.
What I do these days when training/teaching is to go through every stage of the process then have someone else go over it and show that they understand it.
Just thought that some of the things I mentioned may of been overlooked as prior knowledge.
Good luck with it and enjoy.

Here's a link to a two-part video tutorial on how to hand sharpen drill bits.

Got a ton of used drilled bits sitting here, is one thing ive always said i would 'get around to doing' maybe this will give me the motivation

cheers Grahame