Hand Sharpening Drill Bits

[Grahame Collins]

I saw a reference to"How difficult it is to hand sharpen drill Bits" a few posts down the list.
Its akin to waiving the red flag in front of the bull.:((
I can't bear to hear it any more and rather than just moan on about it, I am prepared to do something about it.

I'll state here that its not hard, its just bloody technique and as proof offer some of my own Yr 12 Engineering cherubs as evidence that anyone thats wants to, can learn this skill.:2tsup::2tsup: It's all about attitude folks.If you tell yourself you can't do it you never will.:C

I have sucessfully taught this skill repeatedly and have had some of my students producing twin pigtails from drilled holes in twenty minutes. Not all my kids mind you,but just those interested interested enough to watch and ask questions.

Better than that, one of the kids has been able to copy the 4 facet grind found on one of the manufacturers drills - a Vixen bit - maybe a Sutton or P&N bit.

Who is up for a set of photo tutorials on Hand ground drill bits? The camera batteries are going on the charger now!:D


Grahame

[Gavin Newman]

Go for it Graham, I've been hand sharpening drills for 40 years with reasonably consistent results, it's just a matter of the learning basics and then practice, practice, practice.

[RayG]

Hi Graeme,

Sign me up for a drill sharpening class.

I do ok (sometimes) on larger drill bits, but mixed to hopeless on the smaller ones.

Regards
Ray

[fubar]

yes please sir

[HazzaB]

Hey Grahame,

Please sign me up, I'm sick of buying new drill every other day, I have a box of ' Practice Bits ' Waiting to go :doh:

HazzaB

[dj_pnevans]

I'm up for it.
David

[issatree]

Hi Grahame,
A bit like the others, I have my good days at Sharpening those bits, but the small one are really awkward.
Are going to make a Video / U Tube thing, or can you explain HOW YOU DO IT.
Anything you do or tell us wood be an improvement on what I do, anyway.
Strange as it seems, those drills do cut most of the time, & instead of a point? I have this short line, & they still work, it's got me ?

[Ironwood]

I'd be interested in some refresher training Grahame.

I was tought to sharpen drill bits back in 1981 when I was a 1st year apprentice, by Max Soul, he was one of the apprentice trainers where I worked.

With the throwaway culture in many workplaces thesedays it seems to be a dying art.

[Oldneweng]

I have to put in my bit here. If you are interested in doing it by hand that is great, go for it. I used to be able to do it but now as age sets in (51) and the eyes are finally going it gets more difficult. I don't enjoy sharpening drill bits or chainsaws, so it is just a chore. In my case I just want the drill bit sharpened so I can use it.

A good, properly setup sharpener will give constant results, angles lengths etc with little skill. The skill is in setting up. I use the type of jig which pivots the drill against the side of a grinding wheel or disk. When I first got it I could not get good results. After a lot of thought, observation and testing of angles using CAD I managed to get good results.

This is the type I use.
174895

The instructions provided were wrong and misleading. The other thing I have recently found out and have not yet implemented is that they always instruct the user to use the wrong part of the grinding wheel.

I read this on a web site and a light bulb (Compact flouro of course) lit up above my head. You are told to align the drill with the centre front of the wheel which produces grinding marks along the cutting edge of the drill. All other methods of sharpening align the marks across the edge. Marks along the edge can weaken the edge causing chipping.

The simple answer is align the drill to top centre of the wheel. I made a stand for my grinder to save bench space and then fitted a mount for the sharpener to the side of the stand, complete with adjustments in/out towards axis and up down. I need to change this to align drill with top centre and will rebuild it hopefully better and easier to operate.

Another thing I should mention is that I mounted the sharpener on to a slide that I made which is far more stable and accurate than sliding the base along the bench as per directions. This slide has a bolt to move in/out towards wheel for original setting of position of drill.

An issue that some people mention is in regards to grinding against the side of the wheel. The preasure used for grinding drills is not going to damage a grinding wheel in good condition. If this does bother you use a sanding disk or similar.

If anyone is interested I can supply photos etc to make it clearer and maybe even a drill sharpening class for non hand sharpening.

Dean

[Anorak Bob]

I had a short tempered Dutch boilermaker show me how to sharpen large bits forty years ago. Not having bothered to sharpen a bit since has me at the bottom of the class. I'm keen to see a tutorial for both freehand and jigged sharpening. So fire away Grahame and Dean.

BT

[Pete F]

The problem with hand sharpening a drill bit is that while it's not that difficult, as Grahame says, to get the two edges sharp, it's almost impossible to get them perfectly symmetrical. That's not just my opinion, that's a proven fact when commercial firms have compared the results. Now whether this really matters depends a lot on what you're intending to do with the drill bits you've just sharpened. If you use them in soft materials like wood then knock yourself out, because you won't notice any difference. However if you're after more precise results, like relatively round holes, or you drill deep holes in harder material then be more cautious because the holes created by a drill that's ground asymmetrically will be neither round nor straight.

Personally I rarely find a need to ream holes, and don't have a full set of metric reamers anyway, simply buying them as I need the different sizes. However I do regularly have a need for quite straight and round holes. For that reason I machine sharpen my drill bits. However other members may be in a completely different situation, and hand sharpening may be perfectly adequate. Just be aware of the caveats involved with doing so. It's certainly a good skill to acquire, so I'm not trying to rain on Grahame's parade in any way, just pointing out the limitations.

Pete

[Dingo Dog]

Hi Bloke

I am in too. have one of them Drill Doc thingo's, have not be happy with it, would like to learn the hand technique.

DD

[Oldneweng]

Looks like we are both up for drill sharpening class. I will get to it but unfortunately I am going to have to ask for patience as my wonderful wife is due to have surgery in Adelaide on Wednesday for breast cancer. This is her second time but on different sides.

The doctors are quietly hopeful that due to very early discovery it will be relatively straight forward.

I have a couple of weeks off and may be able to get started in the second week.

Dean

[_fly_]

Go Go Go, I need to know.... While I wait I'm going to calculate how much money I will save on buying new bits. How many old ones can I find to sharpen? I had a mate try to drill stainless. I told him to go very very slow... He went full speed, Started with 1/8 and ruined every NEW bit up to 1/2 inch. Was not impressed as they were MY bits.

[Oldneweng]

I personally have little problem drilling stainless steel. I agree it wears drills bits faster but the biggest problem I think is the hardness and quality of the bits. Using cheapies is a total waste of time. I use a drill press. An electric hand drill is not suitable for SS. I use the same speeds as with steel. After reading your post I did a search and found you were right. About 30% of the speed used for steel. Must try that some time. Also 135 to 140 deg angle for common SS (304, 316). I don't change angles tho.

With the sharpener I use you can sharpen from 1/8in to 3/4in. I also use a spray commonly called RTD spray, for drilling. This stands for ream, tap and drill. It makes drilling noticably easier and faster and reduces wear on both the cutting edges and more importantly the flute edges which determine diameter.

Dean

[wheelinround]

Grahame sitting waiting

I like many apprentices had to learn, stores got sick of us asking for new drills and the storeman sharpening the blunt ones. Poor old Mr Watson he was a top bloke but as has been said his eyesight failing he had to give it up.

He got me one day for being a smart ar_s sharpened it tother way round didnt he :B not god when I was drilling stainless flash on the outside panel or a new vehicle.

I still sharpen by hand but have the same jig as above yet to install it for smaller bits, arthritis and yes eyesight.:roll:

I was clouted for sharpening on the side of the stone, now days its the way.

[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

[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. 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.:) :2tsup:

[BobL]

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.


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.:) :2tsup:

Is this the article?
How to sharpen a drill - Land Yacht Sailing Construction - Seabreeze Forums! (http://www.seabreeze.com.au/forums/Land-Yacht-Sailing/Construction/How-to-sharpen-a-drill/) 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.

[wolften]

Just read Kody's article on sharpening (http://www.seabreeze.com.au/forums/Land-Yacht-Sailing/Construction/How-to-sharpen-a-drill/) 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

[Grahame Collins]

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

[pipeclay]

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.

[Oldneweng]

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

[Oldneweng]

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

[Grahame Collins]

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

[mike48]

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

[Stustoys]

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

[pipeclay]

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.

[tyleryoungblood]

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

http://www.projectsinmetal.com/wp-content/uploads/2011/03/Sharpening-Twist-Drills-By-Hand-Video.png (http://www.projectsinmetal.com/video-sharpening-twist-drills-by-hand-a-2-part-video-tutorial/)

[UglyDan]

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 :wink:

cheers Grahame:2tsup:

[Oldneweng]

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.Just came in from shed about 30mins ago and the last thing I did was take photos of my piece of, oh 8 x 8 x 300mm key steel that I use for the same thing. I use mine for taper shank drills up 25mm and have made another drill mounting bracket to hold these larger diameters.


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 still use my alignment lip rest "thing" as it adds to the accuracy. When a lot of grinding is needed to repair a drill I like to finish off both sides with a light cut which is just a matter of turning the drill around without moving settings.


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.

Good idea. I know what you mean.


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 dropped my jig and the tab that holds the angle at 59 deg broke off. I drilled and tapped and secured a small bolt into position, cut the head off and ground it to produce an edge to replace the original. I ground too far and it is a bit loose. Several other things are missing or damaged so I am going to buy a new jig as soon as I can.


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.
My instruction sheets were downright misleading.


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 find that it is most important to fit the drill in the jig so that the cutting edges are exactly vertical. I don't usually have much overhang, but the bigger the drill the more overhang. This setting of the cutting edges is done with the jig swung around to see or removed from its pivot. Once set and jig is back in position I advance the jig towards the grinding wheel (Grinder turned off) using the slide I mentioned before, until the cutting edge just touches the wheel. I then lock the slide.

If possible have drill feed screw backed off all the way and set a movement for this screw that is estimated to grind the drill enough to clean up. Better to readjust than go too far tho. I have a locking nut at back so when position is set there is a definite and accurate stop. To sharpen an undamaged drill I will only set about a half turn or less. So, square plate is back as far as possible using inside wheel. Outside wheel is screwed up close as well from other side. Back off outer wheel half a turn or so and lock in position with locking wheel. (My addition)

Grind drill. Feed in with inside wheel until it stops. If it cleans up spin and grind other side backing off inside wheel first. If not readjust and repeat. The angles are dependant on the contact point of the drill being at the same angle at all times -vertical. The length of the cutting edges is dependant on the stop not moving, and grinding out at the end the same amount.


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


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

cheerio, mike
May copy some of this later and add detail and pics. I took the first pics today.

Dean

[jhovel]

Kody,
I read your article with great interest and admiration.
I then went to collate the parts to print them off for reference in the workshop.
To do that "nicely", I edited the reference to the multiple parts slightly and formatted them into a single pdf document.
It's attached here - hope you don't mind. If you do, let me knwo and I'll remove it.
Cheers,
Joe

[eskimo]

everybody wants to be a teacher....I thought Grahame was giving the lesson for us dummies:2tsup:
when he's finsihed is the time for you to step in and tell us how you do it
I will get to be able to sharpen a drill...at last:2tsup:

[wheelinround]

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


Nice conversion Mike. How have you mounted it?

Ok so far this thread is generally about larger drill bits ones most of us can grab hold and do free hand. No mention of face definition of drill bit as in if it should be rounded back as I was taught for relief area, type of material being drilled or in particular small drill bits. these are the hardest for old blokes to sharpen.
Such as arthritis (even the young get it), can reduce movement.

In another thread some time back I mentioned being clouted for sharpening drill bits on the side of wheels now days it seems the way to go.:doh: Never knew I was ahead of my time:roll:

[mike48]

everybody wants to be a teacher....I thought Grahame was giving the lesson for us dummies:2tsup:
when he's finsihed is the time for you to step in and tell us how you do it
I will get to be able to sharpen a drill...at last:2tsup:

Grahame,

apologies for my part in steering off course in your thread.

I sometimes just get carried away.

Watching, with keen interest.

mike

[tyleryoungblood]

I apologize also. :doh:

I should have waited until after you had finished your writeup. I hope the info that I (and others) posted doesn't discourage you from writing your tutorial. It's always nice to have several examples to look through when you're trying to learn a skill, so your tutorial is a welcome addition to the forum!

[Kody]

For Joe Hovel and everyone else,
Thank you so much for the great comments about my drill sharpening article, you are all most appreciated. Please feel free to use the information I presented. I only ask that it is not reproduced for profit as it took a lot of personal work to write it and draw the diagrams. When I get time I will peruse it over once more and update the info if/where it's needed. I would love to produce a video of my own technique of drill sharpening but at the moment the time required eludes me. I watched the two videos listed but I am afraid to say that I think a lot of info was left out so I was not very impressed by them. I do all my drill (and tool) sharpening using an 8" x 1" x 60 grit wheel using the normal face of the wheel. The largest drill in my collection that I hand sharpen is 3/4" but I used to also sharpen 1" and up to 1 1/4" dia.
If you read all the comments added to the Sea-Breeze post, you will I hope, find some extra info about High Speed Steel drills relating to the heat produced when they are ground. Please read the info relating to the TiN coated drills. I will do my best this week, to present on this forum, the info on how to shape and sharpen a drill to drill holes safely in shim brass and shim steel. I am hoping that I can take some close up photos to show you all how I do it.
Joe H, I tried to download your combined pages but the article did not load on my computer, feel free to use the info as you wish. I hope the others have had more success.
kind regards to you all :2tsup::U
Kody (Joe B)

[jhovel]

Does anyone else have troubledownloading my PDF file? I tried it on two computers and it works just fine.
Joe - you might try right-clicking and saving the file. There might be a problem with the association od Adobe with your browser....
Joe(H)

[Big Shed]

No trouble downloading or reading your pdf here:2tsup:

[Ropetangler]

Does anyone else have troubledownloading my PDF file? I tried it on two computers and it works just fine.
Joe - you might try right-clicking and saving the file. There might be a problem with the association od Adobe with your browser....
Joe(H)

No trouble here Joe, many thanks to you, Kody and also to Grahame for yet another community benefiting effort. The efforts of the members of this forum, to help fellow forum members, is what makes it so enjoyable just hanging out here. It is just like being at a barbecue with your mates on this forum, yet we range in age from young-uns, probably not yet teen-agers, to those of us at the other end of the spectrum, with one foot in the grave and the other on a pile of banana skins. All swapping info and ideas, passing on techniques, and occasionally taking the mickey - We are all most fortunate for this space.:2tsup::q
Cheers,
Rob.

[Grahame Collins]

Hi,and sorry for the delay, family stuff over the weekend.
Thanks to those that contributed as it reinforces the theory side which is important to the practical.

In order to successfully sharpen our drill bits it is first necessary to understand the basic drill bit geometry. If there is no awareness of how the drill cuts there can be little comprehension of how to sharpen it.

To successfully sharpen a drill bit three things we must recognize that there are equal :
A Cutting Angles
B Cutting edges
C Cutting edge Clearances ( following the cutting edges)

See these in the illustrations below.

Cutting angle –various materials to be drilled respond best to their specific angle for the majority of us,these will not be a concernformost of us and for the purposes of this tutorial can be left out. Those requiring same can find them by googling Drill sharpening angles.We will deal with the basic angle of 118 degrees for steel (A)

As well as being ground to the same angle cutting edges ( B ) must be the same length. One follows the other, as you can't the equal angles without equal cutting edge lengths.

The drill bit cuts in a (very) shallow helix as it slices into the bottom of the hole, so if you didn't grind the non cutting element of the face ( C ) away, it would rub against the bottom of the hole.
In turn this would overheat the drill and cause early failure.


Picture the following in your head. :doh:

When drilling ,the cutting edge on a drill bit is the front edge ,logic says it must be the highest point ,the face( the ground area behing the cutting edge ) then tapers away and below the cutting edge .

If the cutting edge not the highest point of your drill ,the bit will be sitting on the part of the drill that’s not the cutting edge , and will not cut.

See the where illustration M has no clearance. It may cut for a few moments but the heat generated will ruin the cutting edge temper very quickly. Illustration N has a clearance and produces a chip.

Now hopefully that we understand the drill geometry we can go on to learn to place and manipulate the drill bit on the grinder wheel as we shape it to obtain the best possible cutting edge .

Grahame

[wun4us]

Put me in for lessons too...hit or miss with me!!

[Grahame Collins]

Hi,
This safety check list probably seems excessive but it highlights some of the things that can happen when using a bench grinder.
A few checks before start up
RING TEST & RPM MATCH
Inspect the abrasive wheel before mounting it to the equipment. Check the wheel for any visual damage. If damaged, do not use it. Inspect the wheel for internal integrity; this is the "ring test." Tap the wheel "gently with a nonmetallic implement." You can use the handle of a screwdriver or a wooden or plastic mallet for thicker wheels. You should hear a ring. If the sound is more of a thud or dead sound, you likely have a faulty, unusable wheel. Further inspect to make sure the wheel's RPM rating matches the RPM of the bench grinder. • Never operate the wet & dry bench grinder with cracked or damaged wheels.
Always replace cracked or damaged sharpening and grinding wheels immediately.

SPINDLE FIT
Ensure the hole in the grinding wheel fits closely around the spindle.

BALANCE
When a wheel has been newly fitted, rotate it by hand to check the balance before switching on the power

DUST COLLECTION
If the grinder has dust collectors or a exhaust shute , it must be in good working order. Check these before grinding operations begin. Ensure they are clear of clogged waste material and debris that may hinder safe operation.

WHEEL SURFACE IMPACTION
Unless the wheel is ‘dressed’ with a special tool, when pores become blocked or it loses its cutting surface, the operator will have to press harder to achieve the same cutting effect. These additional forces may cause the wheel to shatter. Always use the appropriate type of grinding wheel for the material to be ground. For example, using plastic or aluminium on grinding wheels designed for steel will clog the pores between the abrasive particles.

WHEEL FLANGES
Unless flanges and washers are evenly seated on either side of the wheel before the locking nut is tightened, the wheel can crack and shatter. Always ensure that the wheel has a soft washer on either side to distribute clamping pressure when the nut is tightened. Avoid over-tightening the locking nut as it can exert hazardous forces on the wheel.


TOOL PLATE /WHEEL GAP
The gap between tool plate and wheel should be adjusted to the minimum distance. • The adjustment of the spark arrestor should be made frequently, so as to
compensate the wear of the wheel, keeping the distance between the guard and
the wheel as small as possible, but in any case not greater than 2mm.

GRINDER GUARDS & SHEILDS
Guards should never be removed from a bench grinder. The guards on a bench grinder provide protection in the event of wheel failure, and protect hands and fingers from injury.

EYE PROTECTION
While safety glasses are minimum, a full face shield is always better.

LOOSE CLOTHING
Obviously ,loose clothing has the potential to be grabbed by the wheel.
Gloves are another item which are not safe for grinder use as they have been known to be caught in the rotating wheel.

WORK AREA CLEAN FREE OF SLIP AND TRIP HAZARDS
As with any work area this is a necessary precaution.

RUN UP
Before using the machine, stand aside and allow the wheels to reach operating speed to avoid injury if the wheel explodes during this time. It is the most common time for this to happen.

I now have a bit of work to do a my own grinder needs to be brought up to scratch before I take any pics.

Grahame

[Oldneweng]

I am now back from the big smoke and both my wife and myself have semi recovered from the experience. My wife needs no more treatment, just 6 monthly checks so all looks good for now.

I have thought about the requirements to sharpen drill bits and have determined that there are several important things to consider.

1. The cutting edges of the drill must be set in the jig exactly vertical and the flute stop at the front of the jig should be set to hold this position. Reposition the drill to the stop after setting so drill is in contact with the stop.

2. The Jig must be adjusted so the drill contacts the surface of the grinding wheel in this vertical orientation. Move jig towards grinding wheel while it is not turning, until the drill edge just touches.

3. Grind the drill bit slowly and carefully to prevent overheating etc.

4. Finish both flutes with a small cut, without changing settings, making sure that the drill flute is connecting with the flute stop (A) on each side of the drill. All you do is release the drill clamp, turn the drill around to the other side and clamp again.

The first picture shows my current jig fitted to a slide mechanism I made when I first got this jig. The rear nut on the jig base (B) holds it to the central metal strip which moves. This nut stays tight. The front nut (C) with the rusty steel piece under it locks the slide to stop it moving. This nut is loosened to move the slide. The nut at the right hand end of the threaded rod (D) is turned to move the jig in relation to the grinding wheel. This provides accurate adjustment.

The galv pieces underneath are the current mounting arrangement which will be changed to position the drill sharpening position to 12 oclock on the wheel instead of the recommended 9.00 oclock position which produces a weak drill edge as descibed in previos post.

The rear adjustment wheel (E) on the jig has had an aluminium wheel (F) fitted next to it so it can be locked to prevent movement while grinding. This provides a fixed stop. The front wheel (G) is slowly wound to move the drill into the grinding wheel untill stopped by the rear wheel.

I found that the rear wheel would move causing a difference between each side of the drill.

The second pic is an attachment I made to sharpen larger and longer drills.

While in the big smoke I bought another sharpening jig to replace this one. The instructions with this jig say that the drill bit should protrude about its diameter from the front edge of the jig. It does not say which part of the bit this refers to. It would seem that if this is done using the outer edge of the bit it would work. I haven't had a chance to try it yet.

If you read the woodturning forum you will see I also bought other toys in the Big Smoke. A lot of my info on drill sharpening came from a web sit that I have not been able to find. I have just found it again so for more reading try this page Drill Sharpening (http://www.gadgetbuilder.com/DrillSharp.html)

Any questions,feel free to ask.

Dean

[Grahame Collins]

Hi,
Apologies to all who may have been waiting with bated breath re the hand drill sharpening info.

I thought iIhad better check and keep you all up to date.
I have had some set backs but and hope to present the info to you to you soon.

One problem was my bench grinder the switch was not to work.Thats just been fixed but another problem I have is my Canon camera in macro is not taking pics of the quality that I can use to illustrate the process. With pics I am taking I can see the cutting edge but the clearance is out of focus badly.

Please bear with me until I get it right.

Until that time I would welcome feedback from those that hand sharpen.
Which is your pivot hand ?

Most of the internet info I can find mentions holding or pivoting the drill between the thumb and forefinger of the left hand and depress and turn the drill with the right hand.

Either this was written by a left hander or I am a bit different ( serious comment please I did not leave the door open there for)..

My drills are held ( pivoted ) in my right hand and the drill end twisted and dipped with the left.

I am am interested in what right handed blokes do in regards to which hand is the pivot while sharpened.

In the mean time I will practice with the camera so my illustrations don't look like they are taken with a cheap mobile phone .

Grahame

[RayG]

Hi Graeme,

I'm right handed.

Rotate (twist) with right hand thumb and index finger, dip with the left, starting at the cutting edge angle and dipping down, and rotating clockwise... hope that makes sense..

Regards
Ray

[pipeclay]

I hold the bit with my left hand and lower my right.

When I sharpen my drills I either have my thumb and index finger rideing of the flutes or in the flutes if the drill is large enough.\I start with the cutting edge of the drill square to the wheel.

I then lower /dip my right hand slowly whilst pushing the drill foreward,the helix angle of the drill is pushed past the fingers holding causing it to rotate and sharpen the drill.