Stovebolt.com Forums The Shop Area The Tool Chest Drill Bit Sharpening

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.

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:

https://www.youtube.com/watch?v=Xxl8_rSaJVI

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.

I have a drawer full of dull bits. I need to watch this and get to work.

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 !

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

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!