Drill Bits, Sharpen Or Replace?

[cosmokenney]

I'm curious what the smallest size bit is that you guys can do by hand? Do you use a tip point gauge to verify the tip angles?

 

[whateg01]

I'm curious what the smallest size bit is that you guys can do by hand? Do you use a tip point gauge to verify the tip angles?

Smallest I sharpen by hand is 1/16". I don't use a gauge. I just visually check that the cutting edges are the same length and angle. That's confirmed by equal size chips coming off both sides.

As stated before, a drill shouldn't be relied on for a specific hole size. Even a brand new drill can drill a 5-sided hole. Most of the stuff we do, close is close enough. It's amazing how small of a difference the trained eye can detect.

 

[cosmokenney]

Smallest I sharpen by hand is 1/16". I don't use a gauge. I just visually check that the cutting edges are the same length and angle. That's confirmed by equal size chips coming off both sides.

As stated before, a drill shouldn't be relied on for a specific hole size. Even a brand new drill can drill a 5-sided hole. Most of the stuff we do, close is close enough. It's amazing how small of a difference the trained eye can detect.

Man I don't know if I even have the dexterity to to a 1/16" bit!

 

[ricleh]

I use a Darex XT-3000 Auto sharpener. I sharpen 3/16" to 13/16" inch regular and split point drill bits in the auto mode. It also sharpens left hand drill bits to 1/2", 90 degree spotting bits, brad point bits, regular drill bits to 1 3/16" and countersinks with proper attachments. It will sharpen regular and split point bits from 118 degrees to 150 degrees. Drill point geometries can be adjusted easily. I have sharpened a couple thousand drill bits with this unit and have been very impressed with the results.

 

[paulsomlo]

A lifetime ago when I was in trade school, our first project was to sharpen a drill on a pedestal grinder. This had to be completed before moving on to the next project. Having different jobs involved with my tool making career, I have sharpened thousands of drills, maybe hard to believe, but true. Most have been sharpened on every different industrial drill grinder imaginable. One grinder that I really liked was Optima, pictured below, taken from the internet. Very accurate and could do most any point ever needed. It would split point in the same setup. Made in Switzerland. Very, very expensive new. I ran across a NOS Optima a few years back for a quarter the price of new. Still expensive though. Will it ever pay for itself by me using it? Hell no, not even close. BTW, almost all drill bits bought off the shelf will need to be resharpened, I don't care what brand it is or how much it cost. Biggest problem is the heel is higher than the cutting edge.

If you ever get tired of that Optima, give me a call.

When I was young, we had to walk to the shop - uphill both ways, in the snow. And we spent the first six months sharpening drill bits. But we weren't allowed to use the equipment - we had to sharpen them on the sidewalk, on concrete. When we could drill a hole through hardened steel 6 inches deep with a 1/16" drill bit and have it remain within 0.001" of centerline, we were allowed to advance. But until then, it was sharpen drill bits and sweep the floor. Those were different times.

 

[Rinspeed]

I use one of these: https://www.drill-grinder.com/tdr-srd-drill-grinder-model-80-m/

Got it off ebay for much less than the price of a new one.

We have one of those at the shop and it's a very awesome tool. Been meaning to borrow it for the weekend to sharpen a bunch of bits.

 

[paulsomlo]

We have one of those at the shop and it's a very awesome tool. Been meaning to borrow it for the weekend to sharpen a bunch of bits.

They work well, but they don't split point.

 

[NORTON'S SHOP]

If you ever get tired of that Optima, give me a call.

When I was young, we had to walk to the shop - uphill both ways, in the snow. And we spent the first six months sharpening drill bits. But we weren't allowed to use the equipment - we had to sharpen them on the sidewalk, on concrete. When we could drill a hole through hardened steel 6 inches deep with a 1/16" drill bit and have it remain within 0.001" of centerline, we were allowed to advance. But until then, it was sharpen drill bits and sweep the floor. Those were different times.

I don't think I'll ever tire of it. I got so carried away with it that I have drill bits with different helix angles and point geometry for different materials. Drills go through material like a hot knife in butter. I need to get a life.

 

[steel 35]

80s as a apprentice I learned to sharpen very well,
90s -2000 got new ones at fastenal,
currently have 4 sets, and a new one hidden,
now that my supplier has closed locally i will attempt it again someday!
I sure remember the larger ones requiring a different twist and a fat stone.
My experience with a 1st gen D doc wasn't good had someone else attempt to learn.

 

[zmotorsports]

I'm curious what the smallest size bit is that you guys can do by hand? Do you use a tip point gauge to verify the tip angles?

Personally, for me it is about 1/16" as the smallest as they're getting harder to see lately.

That being said, I started out using my little shop made gauge 40~ish years ago. However, about 20 years ago when I got serious about learning the skill of drill bit sharpening, I used nothing more than my small pocket rule and small protractor to creep up on angles and length of cutting edges.

I was able to take much of what I learned playing with the various commercial sharpeners that attach to bench grinders and copy the steps and motions, then apply them free-handing without the bulky mechanical components.

 

[Whitworth]

If you're breaking that many drills, you're doing something wrong. If you're doing machine work, you shouldn't be relying on a drill for an accurately placed or sized hole.

I own a machine shop and rely on drill bits for accurately placed holes every day.
Sizing may be a boring bar or reamer, but neither will make a hole by itself.

If a drill bit gets chipped, or has X operating hours on it, it gets replaced with new.
I don't waste time sharpening bits when making parts @ $250 an hour.

 

[whateg01]

...
I don't waste time sharpening bits when making parts @ $250 an hour.

I think your situation is a little different than most of us.

 

[LeeG]

Some of you guys sharpen bits more often than I use them. With such infrequent use, there is no realistic way I could maintain the skill for sharpening by hand, so I use my Drill Doctor when I need, and replace when I must.

Lee

 

[RTM]

Smallest I sharpen by hand is 1/16". I don't use a gauge. I just visually check that the cutting edges are the same length and angle. That's confirmed by equal size chips coming off both sides.

I can do 1/16" for my woodworking push drill bits, where it isn't very critical to get it perfect. I am not doing it very fast, but since the bits are long discontinued, I can't throw them away.

 

[Jswain]

I own a machine shop and rely on drill bits for accurately placed holes every day.
Sizing may be a boring bar or reamer, but neither will make a hole by itself.

If a drill bit gets chipped, or has X operating hours on it, it gets replaced with new.
I don't waste time sharpening bits when making parts @ $250 an hour.

Can I have your old bits?

 

[joel63]

While I do agree with you, the fact is, most students who take these classes today really just use the period to goof off. My son took two years off machine shop in HS. He had a leg up since he'd been using machines in my shop for years before that. He and one other student were the only two who actually participated and did the assignments. He said he watched students intentionally screwing up the assignments, drilling into vises, etc.

Jack butts.

 

[theoldwizard1]

Drill Hog has been replacing all of my bits that "break" !

 

[dnschmidt]

I'm a Drill Doctor hater. I could never get it to provide sufficient relief behind the cutting edge. I'm pretty good at using a grinder to hand sharpen anything over 1/8". Living in a major city there are many sharpening service places here in Phoenix that will use a precision machine (like a top of the line Darex) to sharpen drill bits and I've used a couple of them years ago with excellent results. Don't know if they are still in existence but the results achieved at the time were excellent.

 

[isb cornbinder]

My Sterling will sharpen .125" and up to 2.50". It is with great reluctance, I am considering the possibility of shortening the drill trough tail end. The swing takes lots of room.
My long term view says the next owner might need the extra length.
I have several drill angle gauges.

 

[Bert_]

I also have a drill doctor; it works great. There is no way that a human can sharpen drill bits free-handed as consistently and accurately as a DD. Sorry, it's just not possible. And of course, now here come the posts claiming they can. You can claim that, and yes, it will probably look and work ok, but there is no way that it will actually measure consistently like a DD will, time after time. This is like claiming you can weld as quickly as a robot, do wheel alignments with string that equal a modern machine, you don't need a surface grinder because you have a file.....

A guy at the shop was messing around with a drill bit sharpener last winter. Spend a bunch of time trying to get it set up and figure out how to use it.

I could sharpen a bit faster by hand. It cut better too. Bench grinder or even an angle grinder works fine.

 

[Jswain]

A guy at the shop was messing around with a drill bit sharpener last winter. Spend a bunch of time trying to get it set up and figure out how to use it.

I could sharpen a bit faster by hand. It cut better too. Bench grinder or even an angle grinder works fine.

The other benefit is damn near everyone has a bench grinder, angle grinder, belt sander etc.

Learn to sharpen by hand and you can sharpen a bit anywhere, your shop, your old man's shop, your kids shop, your buddies shop.

 

[4 FN 27]

I have to admit I was never very good at sharpening drill bits. Over the years I looked and looked for a good used Black Diamond Grinder and finally one popped up for sale locally here. It had been through the ringer a few times. It was a POS!

Then GJ to the recue!!! Saw a Darex somebody had post and I looked them up online. Called them and talked to the owner and he gave me a really good deal on a new one. I love it.



I found I new friends because of this machine.

 

[dnschmidt]

The other benefit is damn near everyone has a bench grinder, angle grinder, belt sander etc.

Learn to sharpen by hand and you can sharpen a bit anywhere, your shop, your old man's shop, your kids shop, your buddies shop.

Oddly, a belt sander doesn't work. the problem is that you don't get enough of relief. I have three belt sanders and I've tried them all and none of them enable you to get the relief like the bench grinder does as the wheel spins away from the cutting edge. I thought that the belt sander would be the nuts but I was wrong. A bench grinder with a dressed wheel is the best tool for the job.

 

[scooby074]

Under 3/16 or 1/4, I usually replace. Over that, Ill sharpen. Now that Im buying my own drills, I keep to using the same sizes as much as possible for pilots etc, cuts the wear and tear down on the remainder of the index.

Drill doctors (the consumer models at least) are garbage. I could never get mine to work.

I also had to make a drill gauge as a shop project in Trade School !! Hacksaw and file. I should grab a pic next time Im in the shop. I still use it on occasion when I got a real screwed up drill.

 

[dnschmidt]

I have to admit I was never very good at sharpening drill bits. Over the years I looked and looked for a good used Black Diamond Grinder and finally one popped up for sale locally here. It had been through the ringer a few times. It was a POS!

Then GJ to the recue!!! Saw a Darex somebody had post and I looked them up online. Called them and talked to the owner and he gave me a really good deal on a new one. I love it.



I found I new friends because of this machine.

Exactly how good of a deal was it? Inquiring minds want to know. That's about as far from a Drill Doctor as you can possibly get.

 

[scooby074]

Exactly how good of a deal was it? Inquiring minds want to know. That's about as far from a Drill Doctor as you can possibly get.

Darex is (or used to be) Drill Doctor

 

[4 FN 27]

Exactly how good of a deal was it? Inquiring minds want to know. That's about as far from a Drill Doctor as you can possibly get.

Good enough I bought it and slept that night. It was during Charlie-19'er and they were looking to move product.

 

[MongoTA]

For years I had ALWAYS wanted a quality drill bit sharpener, but never came across one with enough of its parts that was in my price range.

I ended up searching through youtube and web tutorials until I finaly found an excellent one from an older gentleman. His explanation, his camera angles, his technique...simply brilliant.

His words made sense. I've tried reloacting that video a few times but I've not been able to do so.

Once you understand the cutting angle, the bit geometry, why it is the way it is? The need for relief behind the cutting edge, etc? It's all obvious once you know about it.

Regardless, I took an old bit and stepped up to the grinder and went at it. Takes a while to build up the muscle memory of movement, but once you do? You've got it. You might lose it on occasion but after a couple of swipes you get it back.

Learning how, and being able to sharpen drill bits is probably one of the more satisfying shop skills I've picked up over the years. It's great comfort knowing I can renew a bit if I trash it.

I have two Kennedy boxes that contain bits, here are the contents of the 5-drawer that I keep near one of my work stations. This photo is from when I was moving things around and taking inventory.

I sharpen them freehand. Only when a bit gets damaged and needs heavy repair, that's when I'll pull out a gauge to make sure the angle and symmetry is where it needs to be.

 

[whateg01]

Oddly, a belt sander doesn't work. the problem is that you don't get enough of relief. I have three belt sanders and I've tried them all and none of them enable you to get the relief like the bench grinder does as the wheel spins away from the cutting edge. I thought that the belt sander would be the nuts but I was wrong. A bench grinder with a dressed wheel is the best tool for the job.

The tool doesn't provide relief, rotating the drill up and away provides that.

 

[darkzero]

Exactly how good of a deal was it? Inquiring minds want to know. That's about as far from a Drill Doctor as you can possibly get.

Although completely different machines, Darex makes the Drill Doctor. They also make the Work Sharp. Both of which are DIY/home gamer grade machines. That's what I meant by "real Darex" in my post. Darex has made various different industrial grade sharpeners over the years. They run like $1200 & up.

 

[zmotorsports]

@MongoTA , very well said. I agree that the muscle memory is crucial and the only way to achieve that is by doing it repeatedly. Practice, practice, practice.

 

[Lassen Forge]

I'm mediocre at sharpening bits, but it's cheaper than buying new ones... and the practice sure don't hurt. If I screw one up, then sure, I'll buy (or get out) a new one, but if I can stretch a bit out until it's to the point you can't effectively sharpen it, then I won! And sometimes, I can even sharpen one right... Maybe.

 

[Wiz02]

My dad gave me a largish drill bit when I was 12 or 13 years old and told me to sharpen it on the grinder. He gave me a general concept and said have at it.

I ground that poor drill bit down to a stub and it was duller than when I started.

I eventually learned to do a half assed sharpening job by hand, but I do it so rarely that I lost the muscle memory.

I just buy new bits for my most used sizes as sadly, many if not most bits in my drill index are unused.

 

[dnschmidt]

The tool doesn't provide relief, rotating the drill up and away provides that.

Which is much easier to do when you've got a curved wheel that by it's simple shape is moving away from you.

 

[bb29510]

my drill doctor was aPOS from day one, best thing i ever did was trash it, I sharpen mine by hand, about three seconds all it takes

 

[278horn]

In our machine shop where hole diameter tolerances need to be held close, this is he fastest, easiest and most accurate grinder for drills 1/2" and below. We use for 135 degree points as well.

For sharpening on a bench grinder, we typically use this gauge.

 

[whateg01]

In our machine shop where hole diameter tolerances need to be held close, this is he fastest, easiest and most accurate grinder for drills 1/2" and below. We use for 135 degree points as well.

For sharpening on a bench grinder, we typically use this gauge.

Looks like a nice machine. Watched a couple videos and it sure looks like it takes a lot of time to set up for each step.

 

[zendriver]

New bits seem pretty sharp and straight. Wonder if they are sharpened by hand?

My machinist bro taught me how to sharpen on a grinder. I could do it, whatever. Closeup eyesight is not all that these days, so I've used my DD a few times, with great results. Learning those three steps is *****, but old dummies like me hang in there.

 

[Renegade1LI]

I have to admit I was never very good at sharpening drill bits. Over the years I looked and looked for a good used Black Diamond Grinder and finally one popped up for sale locally here. It had been through the ringer a few times. It was a POS!

Then GJ to the recue!!! Saw a Darex somebody had post and I looked them up online. Called them and talked to the owner and he gave me a really good deal on a new one. I love it.



I found I new friends because of this machine.

This might be the answer I'm looking for, for what we spend on bits company wide we could save money with this. I don't let anyone sharpen bits on the job, it's much cheaper to hand out new ones. I've had no luck with drill doctor, probably me, this looks great, teach the kid in the shop,a good fill in job.

 

[paulsomlo]

Looks like a nice machine. Watched a couple videos and it sure looks like it takes a lot of time to set up for each step.

It depends - if all you want to do is a basic conical grind, they're very fast. If you want to split point or just thin the web, then yes, you have to change settings, reposition the drill. To do a one off drill, that's a PIA; you really want to do a batch of them, first grinding the primary lip, then switching over to split or thin all of them.