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Dan_the_Chemist
12-04-2017, 10:37 AM
So I was drilling a 1" hole in annealed 4140 and I became convinced that the guy who sharpened the drill is a ham fisted bozo who doesn't know what he is doing.

I was the one who sharpened the drill.

Okay, I'm willing to admit that I don't know what I'm doing. I have read the threads, I have the basic idea in my mind. I can turn a drill bit with a chowdered end into a drill bit that cuts, sorta, kinda... But they ain't really up to snuff. I could spend a day or two practicing until I get better but then I'd have a few indexes filled with stubby drills, and I still wouldn't have confidence that the drill was the best it could be.

Next I tried the This Old Tony technique. I laid the drill on my bench, sprayed it with some WD-40, and tapped it with a hammer. I expected a couple of flakes to fall off the end leaving it perfectly sharpened. Nothing happened. I tapped with increasing vigor. I now have a drill for making holes with a 10 degree bend in the middle. How DOES he do it ???

Drill Doctor - Nope. I do not want to, nor can I afford to buy a Drill Doctor. Money is in short supply and if I raid the bank account for Yet Another Tool then the Missus will do something that involves high accelerations and blunt force trauma to my noggin.

I don't have much money. What I do have is a fair amount of metal laying about, and some nice tools. I have time.

I have decided that the Quorn or Stent tool and cutter grinders are currently beyond my confidence level. That leaves something like a Harold Hall cutter rest with accessories, or a General/Reliant type jig. I bought the books for the HH rests, but I'm wondering if a simple General/Reliant type jig would be easier to make and use for drill bits.

1) What do you guys think?
2) Does anybody have plans or a URL to plans for a General/Reliant type drill sharpening jig?

J Tiers
12-04-2017, 11:29 AM
Sharpening 1" drills is dead easy... really. No kidding. Same down to maybe 1/4" drills. more likely 3/8". Smaller are harder to see and check, plus they are not expensive.

1) the drill needs two sharp edges

2) Behind the edge, there should be a relief of several degrees slope so that the edge touches first when drilling.

3) the two edges need to be the same length.

4) The two edges need to be at the same angle away from the drill axis

For the same length issue, and the angle, get a drill sharpening gauge like this

http://ecx.images-amazon.com/images/I/414YFAG3WWL.jpg

with that you can judge the length of the edge and hit one side some more if you need to even them up, and it also will check the angle.

Truthfully, you should not need more than maybe a quarter inch of drill, no matter how ham handed you think you are, to get lots of practice.

smithdoor
12-04-2017, 12:15 PM
I do all my sharpening with any jig
I my shop I put a line at on a 6" grinder at 118 deg for ever one shop for drill bit
Simple and fast it would take me about 10 min to train to sharpen drill bits
I jig or sharpening machine just something employees would spend time doing nothing but play with machine.

Dave

dalee100
12-04-2017, 12:33 PM
Hi,

To follow on to JTiers reply. For most resharpening, exactness on angles, while important, isn't life or death. Do you own a drill angle gage?

Some photos
https://www.google.com/search?q=drill+sharpening+angle+gauge&safe=off&tbm=isch&source=iu&ictx=1&fir=0PMpvIbc2k-k3M%253A%252CUT6fBsCiHDUTrM%252C_&usg=__b-a2i_V17g6512gpju8WjH7DgZs%3D&sa=X&ved=0ahUKEwik5L3o8PDXAhVRImMKHaUXAmMQ9QEI4wEwBw#im grc=0PMpvIbc2k-k3M:

These simplify drill sharpening considerably. Make or get one. As a young apprentice I was required to make one by hand with nothing more than a file. So they are pretty easy to make.

nc5a
12-04-2017, 01:00 PM
Dan,

I have several tools to sharpen drill bits but generally resort to hand sharpening because it's fast. As others have noted the drill doesn't have to be sharpened perfectly for general drilling operations. If I'm doing lots of holes and/or the holes need to be accurately drilled I'll use my Darex M5 sharpener to dress the drill bits. I know you said you looked at videos about hand sharpening drill bits but did you see this one? I think it's one of the better ones out there.

https://www.youtube.com/watch?v=Qze0GyBxBRY

BCRider
12-04-2017, 04:49 PM
I've always done it free hand on that size. But I'd be the first to admit that we can have both good and bad days for such things. More bad than good I'm afraid....

Some grinding rests come with a V in them at an angle. I believe that's supposed to be an aid for drill sharpening to at least set the angle. If you have such a rest it might help. Or better yet make up a cheap n'easy grinder rest that can accept a quick clamp on fence that you can rest the drill against to set that angle and adjust the table for the drill's thickness so it cuts the proper back relief. Then you only need to worry about holding the drill at the right degree of twist and push into the wheel face or edge. That and remove even amounts from both sides so the chisel point ends up in the middle of the diameter. But at least you're only trying to do TWO things now instead of FOUR at one time.

Every time I sharpen a big drill which doesn't fit into my Drill Doctor I keep thinking of this sort of quickie setup for my bench grinder. But then I only sharpen the darn things when I'm in the middle of something else. And by the time that job is done you KNOW where the thought about the grinder rest has already gone......

Robin R
12-04-2017, 09:16 PM
Do a search for Gadget Builder, then when you get to his site scroll down till you get to drill sharpening. He details a 4 facet drill grinding jig, even if you don't want to go that root it's worth reading everything he has to say on the subject. The linked article on 4 facet drills was certainly enough to make me want to build a jig to do the job, not that I've got around to it yet.

machinejack
12-04-2017, 10:10 PM
Way back when I was teaching at a local Vo-Tec school. I offered a night class for older gentlemen that were wanting to get a taste of machining. One of the best things I did was to teach them how to accurately drill a hole. Sounds simple enough, drill a 1/2" hole in 1/2" CRS and hold it to a 0.010 accuracy. Unknown to them I had ground off one lip off so as to drill a larger hole. Man you talk about some frustrated people most holes were 5/8" or so. After looking at the bits and proposing a few questions a few light bulbs started lighting up. Then we got out the text book and started looking at drill bit terminology. Next question was how to solve the problem. One guy saw the picture of a drill gauge but you know there just wasn't one to be had. To make a long story short. We learnt about lay out, cutting to a line with a hack saw no less. Most were taking quick 1/2" strokes with there saws. "Hay I say's I bought all of that blade so use it." Another lesson learned. Gauges made, lines marked, filed smooth everyone had learned how to use there gauges and everyone was now drilling spot on holes. After the last class several weeks later I asked what every body found most useful knowing no one had a mill or lathe at home, it was making and learning how to use the drill gauge. After all who doesn't have a box of dull bits laying around.

mygrizzly1022
12-05-2017, 03:26 PM
Drill bits 101 2and 3


https://www.youtube.com/watch?v=hJItj_ISurY


Bert

wombat2go
12-05-2017, 04:01 PM
I have a Sears Craftsman 6677 drill grinding attachment.
https://picclick.com/Vintage-Sears-Craftsman-Drill-Bit-Grinding-Attachment-6677-391932638650.html
I spent some time yesterday trying various ways to get it working better.

The problem seems to be not enough rake, especially on smaller drill.

After some fiddling about and adjusting the location of the attachment in front
of the bench grinder, I am getting some reasonable results.

https://app.box.com/s/m2rc1mmj6euz9j2am0xhawemtvyjl0tt
https://app.box.com/s/s5xc8db1mfu8upsyg7nfntruub5i3xud

dbq49er
12-05-2017, 04:36 PM
What I am not hearing is: is your grinding stone tuned up with a diamond sharpener. Is it a soft grinder stone that self sharpens or one of those hard grey stones that is 60 or 36 grit? I have found that my 1" belt sander does a great job if you stay on the flat platen behind the belt, again use the 80 grit blue belt.
It is amazing that the deming bits I have gotten needed to be fixed before I could use them. Yes, bigger bits are easier to sharpen. Like others here, I touch up every bit I put to work. Just replace the small ones, they are cheap and brake often.

Ridgerunner
12-05-2017, 04:53 PM
Something I have never seen mentioned in these drill sharpening threads is to watch the sparks. If the sparks are coming off the wheel or belt side, the sharpening is being done on the relief. If the sparks are coming toward the person sharpening; the sharpening is being done on the cutting edge and extra care must be taken.

metalmagpie
12-05-2017, 05:45 PM
Tip: you can get dang close to a 118 gage by just holding a pair of 1/2" nuts together so they have a single external edge 100% adjacent.

metalmagpie

Dan_the_Chemist
12-05-2017, 06:36 PM
Dan,

I have several tools to sharpen drill bits but generally resort to hand sharpening because it's fast. As others have noted the drill doesn't have to be sharpened perfectly for general drilling operations. If I'm doing lots of holes and/or the holes need to be accurately drilled I'll use my Darex M5 sharpener to dress the drill bits. I know you said you looked at videos about hand sharpening drill bits but did you see this one? I think it's one of the better ones out there.

https://www.youtube.com/watch?v=Qze0GyBxBRY

Darn good video... I have tried the technique shown in it and I have converted some really awful drills into better drills. Still don't know if they are optimum though.

Dan_the_Chemist
12-05-2017, 06:37 PM
Hi,

To follow on to JTiers reply. For most resharpening, exactness on angles, while important, isn't life or death. Do you own a drill angle gage?

These simplify drill sharpening considerably. Make or get one. As a young apprentice I was required to make one by hand with nothing more than a file. So they are pretty easy to make.

Okay... MrPete222 and Marc Lecuyer both have videos about it... I shall make one...

754
12-05-2017, 07:40 PM
Tip: you can get dang close to a 118 gage by just holding a pair of 1/2" nuts together so they have a single external edge 100% adjacent.

metalmagpie

Yeah that works, a few degrees won't make a big difference.
But try to remember shallower angle for harder material, and that is shorter flats, easier to sharpen..

J Tiers
12-05-2017, 07:51 PM
The best reason to sharpen to the "correct" angle is that then the drill gauge fits, and you can more easily check the two edge for being equal.... Other than that, no, exact angle is not super important.

Dan_the_Chemist
12-06-2017, 12:06 AM
Perhaps I should also look at the second part of this problem - the Grinding Wheel.

I have two nice old heavy duty grinders that I bought at garage sales. These things are made from thick metal instead of thin sheet metal. One is a Baldor and the other is a Dunlop. As far as the wheels - well, errrr... I got those at the same sale. The Baldor has white colored wheels and the Dunlop has grey colored wheels. The white seem finer than the grey. I've dressed them once or twice. If it seems to you that I don't really know what I'm doing - then you understand the truth of the situation.

So, what sort of wheels do I want? Should I replace these 10+ year old wheels?

J Tiers
12-06-2017, 12:37 AM
IMO the gray ones are unsuited to most of what "we" do, which tends to be grinding fairly hard things, cutter, etc. The rule is "for hard things, a softer wheel, for soft things, a harder wheel".

The grit in a wheel is designed to fall out as it gets dull. With soft maerial, it gets dull slowly, so a hard wheel that hods the grit is OK. For hard material, the grit dulls faser, and a softer wheel lets it fall away sooner. Using hard wheels, like the typical gray "general purpose" wheel supplied on a new "consumer" grinder, will, when sharpening tools, usually lead to "glazing" of the wheel. That term really means that the grit is dull, but has not fallen away yet. The wheell is too "hard", it holds grit too long for the job you are doing.

A good white aluminum oxide wheel of maybe 60 grit, and on the softer side, is probably good for most tool grinding. Finer wheels can be less nice, they "act harder" and don't remove material very well.

Have you "dressed" the wheels? Even a too-hard wheel can be dressed pretty often and do "OK", although a softer one just needs dressing to reshape it. Any of the gray wheels will need dressing before use, although yours are probably no longer that new. They all might benefit from a dressing before deciding they need replaced.

Do you have the wheel code for the ones on there? It should be on the "blotters", and I would expect it to start with an "A", or "WA".

I like the star wheel /disc type for general dressing of bench grinders, they seem to open the wheel decently. Others prefer a diamond dresser.

mf205i
12-06-2017, 02:03 AM
General purpose wheels are way too hard for HSS. I like the pink wheels from Enco. For hand held roughing of HSS I use surface grinder wheels, 46 grit in the I hardness. On a 6-inch grinder at 3450 RPM use the 7 x 1/2 inch wheels. These are 1 bore wheels so you will need to make a spacer and you could have some guard issues but I assure you that it is worth the effort. This wheel is soft enough that it will stay sharp and dressing is only necessary to true or shape it. I assure you that you will be amazed as to what a proper wheel will do.
This is an old link but I like these.
http://www.use-enco.com/CGI/INPDFF?PMKANO=247&PMPAGE=66&PARTPG=INLMPI&PMITEM=317-1113&PMCTLG=01

Forget the Craftsman-General drill jig. They are a gimmick, very poor. Just keep practicing. I would bet that you are better than you think.

My advice is to forget the bench grinder and get a nice vertical belt grinder instead. Get one that has a minimum of 1hp and runs at 5000 to 6000 SFM. A 40ish grit zirconia or ceramic belt works great for roughing out HSS tooling and a 300 to 400 grit belt is perfect for that final finish. I found that the belt grinder is much easier to judge angles on and be it lathe bits or drill bits, its just a lot easier and faster to get good results. As a bonus you will have a belt grinder! You will soon discover that a belt grinder is one of the most useful machines that you can own, well beyond its initial perceived utility.
I have a lot of bench grinders and these days they seldom get used, with the exception being the ones that are equipped with wire wheels, surfacing-blending wheels, buffing wheels etc.
Best of luck, Mike

754
12-06-2017, 02:30 AM
I prefer the belt slander for drills over 5/8.. once you get over 1 1/4 inch it get tricky on a small grinder.
A word or two on grinders.
The dresser can open up the wheel and get it to cut better, but if they are out if round, I use a diamond to true the wheel first.. hard to grind if its bouncing.
Second if you do this a lot, you will want more than one grinder. For HSS I prefer a roughing and finishing wheel on one grinder.
Then at least one carbide wheel on a second grinder to touch up brazed carbides.
And a zip disc for removing the bulk on HSS blanks and for cutting them in half.

Then at one-time I had a surface grinder, that opened up a whole new world in grinding tool blanks..

J Tiers
12-06-2017, 11:22 AM
The belt sander/grinder is "OK", but I prefer a disk sander if I have to use a sander.

The belt has a tendency to round over the edge very slightly, because it is flexible and flexes away from the tool you are grinding. It is not a huge deal, but it occurs, even a bit when backed by the platen, because the belt is never flat against it. The disk is backed up, and takes away most of the flexing.

Of course a vitrified wheel is not going to flex, and that problem, however important or non-important it may be, cannot exist. And the curve of the wheel allows the height above center to be used to grind reliefs easily, when grinding on the periphery.

H380
12-06-2017, 12:32 PM
Starrett makes a 13D blade that fits the 6" try squares. I bought this as a kit. It is listed on the box as a 13C. I made a guide with only a saw and a file. You just use a guide to get both sides of the bit the same angle and length. So the tip is in the center of the bit. Again it is just a guide for you to grind to. The bigger the bit the easier it is.

https://i.imgur.com/X67rYqY.jpg

754
12-06-2017, 02:29 PM
Actually on a disc belt slander combo... if the belt is vertical, rough the drill on it, then finish it on the disc.

JRouche
12-06-2017, 03:18 PM
2) Does anybody have plans or a URL to plans for a General/Reliant type drill sharpening jig?

Once again. Many opinions re: hand grinding but no answer to the question.. Oh well, I guess that means no plans. JR

J Tiers
12-06-2017, 04:43 PM
Once again. Many opinions re: hand grinding but no answer to the question.. Oh well, I guess that means no plans. JR

Probably. I find them at garage sales for $2 (and ignore them) regularly. I DO have one, and I HAVE used it. As I recall it did "OK", no worse than a Drill Doctor, but more trouble to use.

Since I quit messing with it, and sharpen by hand, that may tell you something.

If anyone wants some measurements from it, I can do that, or I might just do a solid model and then I could supply a STEP file of it.....

754
12-06-2017, 05:16 PM
Probably the easiest way at this point, get a grinder with the drill v groove in the work rest.
Then learn to push in slightly and twist at the same time..

wombat2go
12-06-2017, 08:34 PM
Forget the Craftsman-General drill jig. They are a gimmick, very poor. Just keep practicing. I would bet that you are better than you think.

Best of luck, Mike
I re-ground about 6 old drills of various sizes today on that jig and I have to disagree with your comment.
On each drill I ran it into a 6061 block, and they all cut OK.

Some of the old drills here had bent un-hard chuck ends , so I discarded those.
Some had galled or burred chuck ends where the chuck had skated.

Where those were un-hardened and burred , I wrapped the drill in painter tape and chucked in the 4 jaw in reverse. Set to about < .002 inch ( 50 micron) runout, I ran a skim down the chuck end .

Next I will drill & tap some 1/4 20 tpi which needs the 0.200 inch drill, so I will try to measure and report.

GadgetBuilder
12-06-2017, 09:43 PM
The much maligned Craftsman-General-Draper drill sharpening jig works but doesn't get the drill point geometry quite right across the range of sizes it is meant to handle. Graham Meek suggests some modest tweaks can improve its performance, see: http://www.modelengineeringwebsite.com/Drill_grinding_jig_1.html (My preference is 4 facet so I haven't tried these suggestions.)

John

JCHannum
12-06-2017, 09:54 PM
There is nothing inherently wrong with the Craftsman/General drill grinder jig design, it is the same basic concept found in many drill grinding jigs. The jig itself will work, but is on the lightweight side and is difficult to feed into the grinding wheel.
There have been several writeups dealing with those shortcomings. The link above is a good example of these.

I usually hand grind my drill bits, touching them up before they are a lost cause. I use a disc sander for this purpose. Sometimes, I do find the need to put the C/G fixture into use. At those times, I mount it on my T&C grinder as that provides fine control of the infeed. It does a very acceptable job in those cases.

Dan_the_Chemist
12-06-2017, 10:13 PM
Once again. Many opinions re: hand grinding but no answer to the question.. Oh well, I guess that means no plans. JR

Someone was kind enough to send me a PM and offer some plans. I haven't gotten back to them yet because I've been sort of swamped - in a retired sort of way - I had to cut my afternoon nap short !!! However, since they offered in PM I'm not going to "out" them, except to say that there are nice people out there and "thanks".

Dan

wombat2go
12-07-2017, 12:10 AM
https://app.box.com/s/qi7pa57yqtubniwfwlxjrpgr6frlakc0

A macro photo of the drills sharpened today with the
Sears Craftsman 6677 drill grinding attachment.

Taken with the vintage SMC Pentax -M 1:4 100mm Dental Macro lens with the red magnifier.

TGTool
12-07-2017, 02:25 PM
https://app.box.com/s/qi7pa57yqtubniwfwlxjrpgr6frlakc0

A macro photo of the drills sharpened today with the
Sears Craftsman 6677 drill grinding attachment.

Taken with the vintage SMC Pentax -M 1:4 100mm Dental Macro lens with the red magnifier.

Nice photo and nice looking grind job. The one on the far left must be ground down a ways to a thicker web and would probably be happier with a web thinning. That's for others since I'm sure you already know that.