Drill Bit Sharpening

[PhilHill]

I thought this might come in handy, can't just keep buying new ones. It seems like a simple thing but it's not. But it's not impossible either, just takes some practice.

This here is a twist drill bit. I suspect you already knew that, but it gives a nice view of the various parts. The best point angle for hardwoods is 45 degrees to the center line of the bit. And it makes a difference even though it wouldn't seem so. too sharp an angle or too shallow an angle will change the size of the hole your drilling plus make it harder to keep a straight depth line.


[youtube]https://www.youtube.com/watch?v=Qze0GyBxBRY[/youtube]

This gives a pretty good example of what to do. Like all grinding, don't grind too long before allowing the metal to cool some, if you keep grinding until the metal changes color, you will change the hardness, or temper in the bit. Then it won't hold an edge properly. Hope this helps someone.

 

[rgand]

That's good information. For those who don't have the practice to do this by hand, there are drill sharpeners you can get for reasonable prices. I had one and gave it to a friend because I've spent many years sharpening them by hand and found myself just doing that and leaving the Drill Doctor in the case. I did try it out and it does work good, though.

 

[PhilHill]

That's good information. For those who don't have the practice to do this by hand, there are drill sharpeners you can get for reasonable prices. I had one and gave it to a friend because I've spent many years sharpening them by hand and found myself just doing that and leaving the Drill Doctor in the case. I did try it out and it does work good, though.

Good point. I'm the same way about it. I've spent so many years doing it by hand, it would take me longer to setup the machine than to just grind it and be done.

 

[raystankewitz]

So, I cringed my way through that sharpening video and at the end, when he says all done and ready to go, I'm thinking "Ready for the trash bin."

Even the cheapest Darex Drill Doctor or a grinder with a tool rest and guide, used only for drill bits can top that. His flat flank face ensures it will cut poorly, if at all. I spent a year working with the industrial version of the Darex so I have fixed all manner of badly sharpened bits. In all my years, I only know of one person that could pull off a decent freehand sharpening and she was a thirty year veteran of a machine shop. Even she admitted the Darex was superior to hand sharpening.

Sorry if I stepped on some toes, I usually don't do that but sharpening drill bits by hand is one of my hot issues.

 

[mayfly]

I've got A drill bit sharpening jig that you use with a sharpening stone.  The first bit I tried to sharpen with it I completely destroyed  . 

I've never touched it since, but now some of my bits are getting rather dull.  I looked up the drill doctor, and those things look very interesting.  I might have to invest in one soon!

 

[PhilHill]

So, I cringed my way through that sharpening video and at the end, when he says all done and ready to go, I'm thinking "Ready for the trash bin."

Even the cheapest Darex Drill Doctor or a grinder with a tool rest and guide, used only for drill bits can top that. His flat flank face ensures it will cut poorly, if at all. I spent a year working with the industrial version of the Darex so I have fixed all manner of badly sharpened bits. In all my years, I only know of one person that could pull off a decent freehand sharpening and she was a thirty year veteran of a machine shop. Even she admitted the Darex was superior to hand sharpening.

Sorry if I stepped on some toes, I usually don't do that but sharpening drill bits by hand is one of my hot issues.

Your post would be fine if it were not complete complete horse manure. If you only ever met one person who could hand sharpen a drill you obviously never spent much time in machine shops or tool rooms. At least not good ones. And yes, a Drill Doctor can do a better job than inexperienced people. That's what it's made for, folks that don't sharpen drills for a living. But it also gives you no understanding of how sharpening affects the drill and no experience in how a drill works. It gives you no experience in how to work with tool steel, or how to sharpen tools, or how grinding affects metal and how to achieve what you need in the way of a cutting edge. And thirty + yrs as a machinist tells me there's nothing wrong with the face of the drill in the vid.  :icon_thumright:

 

[Rick]

I go thru so few drill bits I just buy new ones.

 

[PhilHill]

It occurs to me that my previous post was kind of improper as I let my temper get away from me. I apologize to the forum for that.
A Drill Doctor is great for folks who only need to freshen up a few drills every once and awhile. But I didn't care for the OP denigrating the practice of learning to sharpen by hand. If a person uses a fair amount of cutting tools, not just drill bits but chisels, planes, router bits, scrapers, etc. learning something about how to sharpen a cutting edge can be an important and handy experience. It's part of the practice of taking care of ones tools and understanding them. No, it's not needed by everyone, I fully agree. However for those that want to develope the ability, it has far reaching benefits outside of just drills.

 

[rgand]

I'm in agreement with you on learning to sharpen by hand. When I was tall enough to work on the bench, my father taught me how to sharpen hand tools (chisels, knives, planes, etc.). When I was tall enough to use power tools, he taught me how to sharpen them. Been doing it ever since. It sure saves time and keeps projects moving.

 

[Rick]

Actually this weekend I sharpened my lawn mower blades

 

[PhilHill]

:hello2: :headbang: