Posted By: 2-Ton Drill Bit Sharpening - Fri May 18 2018 11:36 AM
John at the homecoming asked me to do a seminar on how to sharpen drill bits.
With the cooking and all the other activities going on, we did not get a chance to do that.
But I have come across a how-to video that will show you how, on a belt sander.
You can also sharpen them on a bench grinder the same way.

Hope this helps!
Posted By: Grigg Re: Drill Bits - Fri May 18 2018 01:23 PM
Here's another drill sharpening video with more technical info and humor.
Posted By: 2-Ton Re: Drill Bits - Fri May 18 2018 02:12 PM
Good video Grigg III.
I really liked the humor and how he explained how a drill works.
Of course there are some more tricks for different types of material.
Speeds, feeds and lube are also a big factors.
But for most of us, it gives a better understanding, of how a drill works.

Wonder if this should be moved to the tool threads?
Posted By: VEW Re: Drill Bits - Fri May 18 2018 03:28 PM
Thanks guys. I learned something today.
Posted By: John Milliman Re: Drill Bits - Fri May 18 2018 09:17 PM
Thanks Don! This is good info -- Good idea about moving it to the tools forum.
Posted By: Fred T Re: Drill Bits - Sun Jul 15 2018 06:26 AM
I have a friend who is an expert at sharpening with a belt sander. My dad did a decent job with a grinder. My hands shake too much, so I use a Drill Doctor. Used properly it does an excellent job.
Posted By: GIJOE298 Re: Drill Bits - Tue Jul 17 2018 12:48 AM
I agree Fred. I use my drill doctor all the time. sure beats fighting a dull bit!
Posted By: Hotrod Lincoln Re: Drill Bits - Thu Sep 13 2018 04:20 AM
Once the bit is sharpened, it stays that way a lot longer if it's lubed well. I like to use non-salted lard, mixed with a little Diesel fuel or Kerosene as a drilling lube. On those slow, heavy cuts, it smells a lot like bacon frying! Most people run drills too fast, too dry, and don't put enough down pressure on the bit. At the right RPM and down pressure, a sharp bit will roll a continuous tight spiral of cuttings out of the hole. If you let the bit "skate" without making chips, it will overheat and dull itself in a hurry.

Posted By: MNSmith Re: Drill Bits - Thu Sep 13 2018 12:56 PM
It's amazing how many of those beautiful drilling and tapping cans of oil I have around the shop. I say beautiful because they go un-touched by most of the guys. My can look pretty well used, though.
Posted By: delux54panel Re: Drill Bits - Fri Sep 21 2018 05:37 AM
When i worked at Naval Weapons Station, Concord, the machinist gave me a Plews Oiler with Trans fluid and Diesel that he used for cutting oil.
Still have that, and still use it.
Posted By: coilover Re: Drill Bits - Fri Dec 21 2018 01:17 PM
Yes, speed is everything when it come to drilling. Our drill press has 12 speeds but often there is nothing that is correct for the material being drilled so we then use the mill with infinitely variable speed. With the right speed most everything can be drilled with a HSS drill with no need for cobalt or carbide. Have drilled through leaf springs and spring steel bumpers without a problem. Usually use the old sulfur base cutting fluid for small jobs or hook up the fluid pump for big jobs. The fluid in the pump reservoir takes a cup of concentrate to a gallon of water and is much easier to clean up than oil base fluids.
Posted By: yar Re: Drill Bits - Sat Jan 19 2019 02:59 PM
Decades ago when I took a machining class at a local high school I was taught what I thought was the simplest drill sharpening method that could possible exist, way simpler than any other I've ever seen. Then along came this video that demonstrates an even simpler method:

I haven't tried it yet but I intend to. It seems like it requires no skill at all, just some dull drill bits and a bench grinder.
Posted By: Don T Re: Drill Bits - Tue Feb 26 2019 08:19 AM
I have a drawer full of dull bits. I need to watch this and get to work.
Posted By: fixite7 Re: Drill Bits - Wed May 27 2020 02:32 PM
I mostly use Ridge black or clear cutting oil my dad (gone54 yrs now)said that black oil has sulfur in it makes the tool wanna cut ! on slow rpm like drilling leaf spring holes i think he was right ! also on stainless Ridge clear cutting oil is all that will work says right on the jug for black pipe or stainless steel pipe with their dies made s.s. nipples for burial work...will last a looong time ! some of those specials work fine too !
Posted By: Doc.Hall Re: Drill Bits - Sun Jun 14 2020 12:09 PM
I have a Black & Decker drill sharpener back when B&D made good products (1960's). It has two adjustable rails and is powered by a very old but good Millwaukee 3/8's drill. it was my dads. It has an angle setting which I'm pretty sure I set at 45 degrees. I only sharpened a cheep set of Chinese bits that were given to me as a gift. Completely useless on many levels. I agree I set them on the wrong angle. The new ones will start to cut but even on a slow speed and diamond cutting oil they will break off. Solution the trash recycle bin has a full set. Now I know how to sharpen a 1906-1907 complete set that a machinist that worked for Stanly Steamer gave me about 40 years ago in two solid oak chests along with huge & long bits. I have only used a few of them and they cut like a laser, well almost. My question is are different larger sizes of bits sharpened at a different angle? Thank you yar for the U tube lesson. Doc
Posted By: Phak1 Re: Drill Bits - Sun Jun 14 2020 03:30 PM
The angle should be 30 degrees on a conventional grind. I’ve sharpened thousand of bits by hand during my career as a machinist and the video is spot on. The problem arose when we needed a hole to be exact. Getting the point in the exact center Is difficult by hand and can really be accomplished consistently by a dedicated drill grinder. If the point is off center, it will cut a larger hole. The other issue is grinding very small bits such as 1/16” and smaller. Also try resharpening a drill that you snapped off a half inch or so. Very difficult to re-establish the proper geometry by eye. We in the shop bought a dedicated drill grinder and once set-up properly made sharpening exact and very easy. I found an old General drill grinding attachment at a yard sale years back and use it on my bench grinder.

A note on cutting fluids. Early in my career we used “Cutting Fluid” which was petroleum based by the gallons. This stuff worked great on any milling, drilling or lathe operation, but smoked like crazy, and was difficult to clean up the machines after. In the eighty’s we started using both water soluble coolant on our larger drilling operations and 16 oz. cans of Rapid-tap on the smaller drill presses. The advantage to the water soluble coolants was it didn’t make a mess, cleanup was minimal and the fumes were tolerable. Imaging flooding a 3” drill bit with gallons of oil based coolant? Cleanup would be a job in itself not to mention the all of smoke coming off of the bit. It does not lubricate as well as an oil based coolant/lubricant but with larger machining operations it did the trick. The advantage to Rapid-tap and similar products is in addition to a lubricant they also contained a coolant that evaporated very quickly keeping the bit cool.

Just my two cents!
© The Stovebolt Forums