Drill bit sharpening

[BlacknTan]

When I started my trade as a Diemaker in 1968, this was one of the first things I learned. My mentor gave me a big box of dull drills, and after i wolfed down my lunch, I'd go to the grinder and practice. Once one realizes that tools cut metal by a wedging action, and understand the clearance is needed everywhere, it becomes a pretty simple task. I could sharpen very small drills by hand also, until Father Time took his inevitable toll... But, I can still get the job done. It's like riding a bike, once one learns properly, you never forget!

Learn the fundamentals and practice. Like any manual skill, there's not much more to it than that.

 

[Steave]

Same here. Just couldn't get the hang of it, just ended up making them worse.
Picked up a drill dr. at a yard sale for $25, much better.

Boss man purchased a drill doctor. I think it was the best one available at the time but we could never get the hang of it, not sure what we were doing wrong or if maybe something else was wrong?? A lot of folks have them and love them. I'll probably just keep on sharpening. As I said earlier it don't always work so just chunk it in the scape box.

 

[lostcause]

You'd be surprised how many folks don't resharpen their bits. I have lots of bits I've picked up over the years while on construction jobs. They are laying everywhere, some broke but most just a little dull.

for most cases the simple answer is economics. small bits are very cheap and labor isn't cheap anymore. larger bits are certainly worthwhile to resharpen, but i'd bet that anyone in business wouldn't sharpen bits under 3/8", or maybe even larger, especially if you are out on a jobsite. if you are in a shop that has an apprentice, or floor sweeper, or other low-end job, you can always task that person to resharpen bits when there is nothing else needed, but otherwise you probably don't want an employee sharpening bits while the expensive machine that uses those bits sits idle.

 

[Steave]

for most cases the simple answer is economics. small bits are very cheap and labor isn't cheap anymore. larger bits are certainly worthwhile to resharpen, but i'd bet that anyone in business wouldn't sharpen bits under 3/8", or maybe even larger, especially if you are out on a jobsite. if you are in a shop that has an apprentice, or floor sweeper, or other low-end job, you can always task that person to resharpen bits when there is nothing else needed, but otherwise you probably don't want an employee sharpening bits while the expensive machine that uses those bits sits idle.

Yea, you're right. Thanks to the throw aways I have enough bits to supply me and family & friends. I worked at a small family owned shop and we shared info simular to this Forum except about other topics. You're right we wouldn't take time during the day to sharpen bits but after hours we'd piddle around with different stuff.

 

[crazyal]

I use to do them by hand on a grinder. Now I use the drill doctor. I was taught by necessity as a kid. Either I learned to sharpen bits or I wasn't going to be able to repair my atvs or dirt bikes. You quickly learn to compare good bits with ones you sharpened to figure out what you did wrong. You also experiment with angles.

With the DD I can look at the bit once done and know right off if I've done it correctly. Also the DD gets the angles correct every time. You would be amazed how far off you can get when you sharpen a bit over and over again.

 

[Steave]

You may remember many months ago, I asked about sharpening drill bits on a grinder, and I said I had someone to teach me. Well I never did get around to talking to him, but I had watched a few videos. Yesterday, I decided to grab a dull bit, and try sharpening it on the new grinder. All I can say is wow. It cut steel like a new bit. I have since gone through my assorted dull dormers, some old post drill bits, and a bunch of morse taper bits, sharpened them, and they all cut aluminum like butter. I am for the first time getting curly shavings with a hand drill. It is so easy to do, and takes so little practice, I am shocked more people dont do this. After learning it in 1 bit, I cant believe those drill doctors sell at all. Now I cant wait to set up a bit only grinder. :drool:

When you set up your bit only grinder are you going with a regular grinder or are you going with the slow wheel and water bath? I've always wanted a water bath slow wheel grinder. Think they're mostly for chisels and tools of that nature but still have considered one.

 

[Oaktree]

Boss man purchased a drill doctor. I think it was the best one available at the time but we could never get the hang of it, not sure what we were doing wrong or if maybe something else was wrong?? A lot of folks have them and love them. I'll probably just keep on sharpening. As I said earlier it don't always work so just chunk it in the scape box.

Guy I bought mine from called it Dr. Kevorkian...apparently he killed enough bits in it. I got the hang of the DD pretty quick, even without the manual. YMMV I guess.

 

[deereman75]

When you set up your bit only grinder are you going with a regular grinder or are you going with the slow wheel and water bath? I've always wanted a water bath slow wheel grinder. Think they're mostly for chisels and tools of that nature but still have considered one.

I have an old belt drive grinder, I am going to tune up, and put on 8 inch norton 3x wheels. Cut faster, last longer, and run cooler. Eventually, I want to get an 18 inch wet stone, but nor for a while. After I set up the bit grinder, I will probably build a 12 inch grinder. Also, at school today, the metal shop teacher (a tool and die maker) showed me the right angles, and some other advise. He said except for the angle, everything else was perfect. Not bad for learning how to yesterday.

 

[lostcause]

i think the knowledge and experience of how to sharpen a bit is invaluable to learn, but probably becoming increasingly useless in practical application. everything we do in life becomes more automated as the years go by. the only time things are done "old school" are tasks done for ourselves, and not ones done in daily production. picture a contractor telling his guys to use hammers and not nailers. how about using hot rivets instead of bolts? time is money, and old school just won't cut it anymore in the production world. i believe the same to be true of drill sharpeners. machines are consistent and accurate, where people aren't - no matter how much they argue otherwise.

at the same time, i believe it is always important to understand the basic mechanics behind the operation of any tool. this helps when understanding why something isn't working the way it should, or when you need to do something and you don't have access to the hardware that does the task. i work in a field that is predominately computer controlled now, but i believe that all people who learn should understand how it works when done without a computer. this makes the operator better able to understand the hows and whys that the machine takes care of automatically.

 

[deereman75]

i think the knowledge and experience of how to sharpen a bit is invaluable to learn, but probably becoming increasingly useless in practical application. everything we do in life becomes more automated as the years go by. the only time things are done "old school" are tasks done for ourselves, and not ones done in daily production. picture a contractor telling his guys to use hammers and not nailers. how about using hot rivets instead of bolts? time is money, and old school just won't cut it anymore in the production world. i believe the same to be true of drill sharpeners. machines are consistent and accurate, where people aren't - no matter how much they argue otherwise.

at the same time, i believe it is always important to understand the basic mechanics behind the operation of any tool. this helps when understanding why something isn't working the way it should, or when you need to do something and you don't have access to the hardware that does the task. i work in a field that is predominately computer controlled now, but i believe that all people who learn should understand how it works when done without a computer. this makes the operator better able to understand the hows and whys that the machine takes care of automatically.

For my use, I would rather sharpen them with a grinder I have, then buy a tool that can only sharpen bits. If I had to sharpen like 50 bits a day, then I can see getting a sharpener. I agree that if I was a pro shop, I would likely have a sharpener.

 

[undercut]

Without fail, every time one of those Drill Drs goes on sale, I seriously consider it .... until I figure out how much I would save if I sharpened rather than buy a new bit. Don't go through many drill bits. Makes me wonder what I'm missing!

 

[not2old]

I worked in a machine shop as a kid, and learned how to sharpen drill bits there. I have a Drill Doctor, but rarely use it unless I'm drilling stainless and need lots of well sharpened bits. The Drill Doctor does do a better job, and those bits will drill a more accurately sized hole. You will also have better luck with a less than perfectly sharpened bit if you use a pilot hole and keep enlargening it to the finished size.

 

[Steave]

Without fail, every time one of those Drill Drs goes on sale, I seriously consider it .... until I figure out how much I would save if I sharpened rather than buy a new bit. Don't go through many drill bits. Makes me wonder what I'm missing!

As far as saving money on resharpening it would take a while to justify the price of a DD. I don't use a DD but do sharpen my bits. It only takes a couple of seconds to touch it up on a sander and using a sharp bit makes a LOT of difference. I pittle around with old farm plows and end up using a hand drill so need those bits sharp. I've used bits in my drill press that couldn't be used in a hand drill (to dull). So I guess it comes down to making it easier to work with is my reason for sharpening and I'm kinda cheap ..uh.. thrifty.

 

[undercut]

Well, there certainly quite a few resources available on how to manually sharpen bits. I'll have to give it try at some point. Broke the tip of one my hss bits. Maybe I'll give it go on that one.

 

[deereman75]

Well today in wood shop, there was a brad point bit missing the point. The teacher said he would normally pitch it. In about 3 mins on the baldor bench grinder, I turned it into a razor sharp twist bit. Turned a piece of scrap into a $15 bit. I am getting good at this.

 

[tglass]

Have a Drill Doctor and quite honestly after reading all the threads, and trying to sharpen them by hand...it's easy to sharpen one by hand if you listen and learn the correct way. If you don't want to learn buy the DD and you can spend time sharpening bits when I'll be sitting in the couch. I'm glad someone on this forum taught me how to do this.

 

[Shield Arc]

I am getting good at this.

Good for you!:thumbsup: I'd guess less than 1 % of the people I've worked with over the years could sharpen a drill bit by hand.

 

[KYErik]

I like my DD. I feel that it gets the two cutting edges a little more even than I can get them by hand on the grinder and it is more of a "no brainer"/less thinking/less eyestrain than grinder sharpening.

Broken bits require time on the grander for reshaping (the DD can't do this).

My DD was frustrating me a few months ago- I was getting "negative relief" (sounds frustrating huh?). It was taking more off the cutting edge than it was off the area behind it (so the cutting edge wouldn't touch the metal). It turned out that my set up jig depth adjustment had slowly worked its way loose. I readjusted it and everything started working well again.

 

[Johnp33]

I worked at a truck dealership, and I collected all the drill bits others threw out because they were dull. I have a drawer full of bits, it always amazed me that most people did not want to know the right way to sharpen a bit.
You also can sharpen a drill bit flatter to drill really hard material.
Just a thought!

 

[crazyal]

What finally pushed me over the edge was when I was doing an engine swap in a dump truck. There was lots of 1/2" drilling to be done and the steel was something harder than mild steel. The best solution seamed to be start off with an 1/8", then a 1/4", a 3/8" and then the 1/2" Cobalt bit. Even using cutting fluid I could drill about two holes before the bits started to dull. After about 4 holes the bits had to be sharpened as any further attempts to drill with them would overheat the metal.

The dump truck is a 2 1/2 ton so when I was working on it I wasn't close to the house (where the grinder is). After repeatedly walking back and forth to sharpen the bits I finally unbolted the grinder from the stand and made a temp mount on the front bumper, it worked but not great. Before moving the grinder I tried using a 4 1/2" grinder but that was too difficult. That night I bought a DD so I can bring it to the work and leave the grinder on the stand.

Now the grinder rarely gets used. If I break a bit I'll use it to shape the bit.