How do you sharpen you drill bits?

[Aukai]

I'm sharpening 1" plus bits right now, like it or not I'm learning to do it by hand. I got 1 really close, and it cut like a dream. Even a blind squirrel finds a nut once in awhile

 

[GunsOfNavarone]

I have one of those clunky contraptions that mounts to a table in front of a bench grinder. Problem is, my bench grinder is mounted on a 4 ft schedule C pipe welded to a brake rotor...so I've never used it. A sharp (evenly sharpened/know what you're doing) sort of falls into the same world as cutting your own HSS lathe tools. It takes skill and experience. I'm partially shamed to say it, but I buy good sets and replace them as needed. SOMEDDAY I'll mount my jig and try it out. Getting the right angle and removing the same amount from each flute? My time is so tight I'd rather do something else with that precious commodity.
My hats off to you that do this well and I feel those that waste a half hour to ruin a $5 piece of steel/carbide/chinesium

 

[horty]

Hi,
I thought by hand was the only way, different steels need a different grind, just my opinion.
I was 17 and my first job was at a job shop, was all excited to learn to weld better and do machine work.
Showed up to work Monday morning and was told to start sharpening a few drill bit, the boss took me around the corner and said start here with the small ones and let me know when your all done... I thought I was going to throw up and really thought about quitting.

There must have been 700 drill bits in trays on that wall, from small # drills to 4" drills.

If I remember right it took about 5 weeks, I got better and better at sharpening drill bits and to this day I will never forget how to do. It's tattooed in my brain and something I will never forget how to do.

Tim

 

[Lo-Fi]

Do all mine by hand on a bench grinder. Life is too short to struggle with dull drills, so I taught myself years ago. Tried a few cheap commonly available contraptions including the drill doctor, but been less than impressed. Once you get the feel for it, it's hard not to hit the right geometry and only small drills <5mm are particularly tricky.
Practice on large drills would be my advice for anyone learning. Everything happens slower and you can see what's going on far more easily.

 

[horty]

Definitely watching this!
I tried sharpening a 1/2" bit that was beyond dull. Used my belt grinder and I was very surprised at how well it cut considering I had never tried sharpening before.

You'll get good at it.

Take a known dull bit, put a little magic marker or machinist blue on the cutting end, try to drill with it, then look at it with a magnifier.

You'll see exactly where and what to grind, pretty soon it will come natural to you.

Tim

 

[DavidR8]

You'll get good at it.

Take a known dull bit, put a little magic marker or machinist blue on the cutting end, try to drill with it, then look at it with a magnifier.

You'll see exactly where and what to grind, pretty soon it will come natural to you.

Tim

Good idea Tim, I will definitely try that!


Sent from my iPhone using Tapatalk

 

[mickri]

I routinely use dykem on drills when I sharpen them. Especially if the drill doesn't seem to cut properly. I also put dykem on HSS tool bits when I sharpen them. And I use a magnifying glass to look at the bits. That really helps my aging eyes to see what is happening. I can not sharpen a drill by hand to save my soul. I have tried and tried without success. So my swing thingy was a god send and works for me.

I think that the consensus of this thread is to figure out what works for you. Not somebody else. And keep doing what works.

 

[WCraig]

I have the craftsman version of the swing thingy (Like that name for it). Mostly I get good results yet sometimes not so good. Using the side of a grinding wheel gives me pause at times. I have also notice that I get a groove in the side of the wheel and have to dress the side. Maybe my wheel is too soft. I have no idea what make or grit it is.

I have seen a swing thingy used on a belt sander. Plan to try that out on my belt sander. The 1" belt may be too narrow.

I have wondered if there are wheels that don't cost an arm and two legs that don't risk exploding. I'd like to add a disk to my belt sander for sharpening drill bits. Might have to make a combo disk/pulley. There is enough length on the motor shaft to add a disk. Oh well. Another project for another day.

I use this version (from Lee Valley Tools) with my 1 inch belt sander:

Sharpening by hand has never worked for me. Maybe I'm overthinking it, but maintaining a contact angle while rotating and swooping the drill seems...challenging. For me, the jig is very quick and consistent. It automatically gives the clearance behind the cutting lip. Even horribly mangled bits can be resurrected in just a few minutes. All for $25 (Canadian).

The jig has it's limits, though. 1/8" through 3/4" sizes. Extra long bits won't fit. You may need to put a collar on S&D bits to get them to register properly.

Craig
PS Many, many years ago, I did some project work in a place that made grinding wheels. One of the key takeaways was that you don't want to be anywhere near an exploding wheel. Ever. Using the side of the wheel is not recommended. That's why I have this jig set up on the belt grinder. YMMV.

PPS Just realized the picture above shows the jig improperly assembled. The part that supports the tang of the drill is on backwards.

 

[GunsOfNavarone]

I use this version (from Lee Valley Tools) with my 1 inch belt sander:

Sharpening by hand has never worked for me. Maybe I'm overthinking it, but maintaining a contact angle while rotating and swooping the drill seems...challenging. For me, the jig is very quick and consistent. It automatically gives the clearance behind the cutting lip. Even horribly mangled bits can be resurrected in just a few minutes. All for $25 (Canadian).

The jig has it's limits, though. 1/8" through 3/4" sizes. Extra long bits won't fit. You may need to put a collar on S&D bits to get them to register properly.

Craig
PS Many, many years ago, I did some project work in a place that made grinding wheels. One of the key takeaways was that you don't want to be anywhere near an exploding wheel. Ever. Using the side of the wheel is not recommended. That's why I have this jig set up on the belt grinder. YMMV.

PPS Just realized the picture above shows the jig improperly assembled. The part that supports the tang of the drill is on backwards.

That’s the contraption I have. So you use on a belt sander? That sounds more logical as it’s flat, but what do I know about this topic?

 

[pontiac428]

This is a book in our (HM's) download library that I find excellent as a reference and keep near my sharpening station.

38 - Tool and Cutter Sharpening.pdf

Imported files from vBulletin files system.

www.hobby-machinist.com

He uses the swingy-thingy well and explains some key tips in the 3 or so pages that cover twist drills. It is a good system, in spite of seemingly janky materials and construction. You can mount one any number of ways to meet a moving plane of abrasive, so mounting it on a belt sander seems natural to me.