Drill doctor

[Sal Lubrano]

I have been sharpening some drill bits with a 750x drill doctor without any good results. The drill bits I sharpen are not cutting very well if at all. Those of you who use this sharpener what drill bit angle do you use? Are you splitting the points? Chisel and relief angle?

 

[charlief1]

From what time I used the "drill doctor" the points last 1 time and need some improvement. I've got 1 of the cheap harbor freight units and it's worked OK but not as good as learning how to do it right.

 

[Chuck Leeper]

Mine is gathering dust..NE1 that wants it, pay the ride, it's yours...

 

[TurboBuRick]

I laughed when the drill doctor came out. I been sharpening drill bits on a bench grinder for 20 years. Learned from a old timer. One of the most use full skills I ever picked up.

 

[aminga]

Mine is gathering dust..NE1 that wants it, pay the ride, it's yours...

I'll take it.

 

[Mike E]

You should sharpend them to 118*. I've never used a drill doctor so I can't answer your other questions. Anything under 1/2" I replace when it gets dull, anything over I sharpen by hand. If your drills aren't lasting after sharpening them, it's probably not becuase of how you sharpen them, but more because of the quality of the drill and the rpm your using them at. Buy better quality "Made in the USA" drills and they will last 10 times as long as cheap department store sets. I get hundreds of holes in steel in my fab shop before I replace or sharpen a drill

Some tips for proper rpm that will help you save the drill bits:
The harder the material, the slower the rpm.
The larger the drill diameter, the slower the rpm
When cutting steel, if you see blue chips coming off the drill, your going way to fast. If you see gold, your just about right.
There are smart phone apps that will tell you exactly what rpm for what size drill and what material, but that won't help you much with a hand drill when you don't know what speed it's turning.