Sharpening drill bits

[5030]

I've been using the Drill Doctor for years on bits 3/16 & larger. Anything smaller takes more effort than it's worth. I just toss them & replace.

The box store drill doctor has limited capacity whereas the professional Darex drill doctor has a much wider range and a much higher cost as well. I have one and it sharpens end mills as well. Around 3 grand. Bought mine at a machinery auction for a grand.

 

[PILOON]

I think it's a steady hand more than a fancy drill bit holder.
All I can say is I can drill all day with no problems.

 

[Larry Caldwell]

I've been using the Drill Doctor for years on bits 3/16 & larger. Anything smaller takes more effort than it's worth. I just toss them & replace.

It's that hour and 45 minutes to get to the hardware store that is the problem. You can also do lathe tools on a bench grinder, and it's right there. No gasoline required.

 

[jjeff]

Anyone ever free hand sharpen pilot point cobalt drill bits? If so how? Should I just grind what's left of the point off and try and sharpen it like a regular bit?
Thanks

 

[sd455dan]

I have had an older (Blue, Tall cube shaped one) DD for years. It seemed to work really well for many years and then the last few times it was hit or miss. It may be I need to order a new grinding wheel for it. It also seems like I have to make sure I hold the bit by hand real tightly when I place it in the alignment port and tighten the collar or it will rotate.

I have successfully sharpened some larger bits 1/4" and up on the bench grinder.

It is really satisfying when you use a bit you sharpened either way and it produces large shavings or spirals instead of fine shavings and drilling a hole only takes a few seconds.

Did a search and I have the Classic Model 500 or maybe the 750. Classic Model 500 - Drill Doctor
I have to say, I like how it looks more substantial than the current models.

Same have the old Classic 750, I always test the bits on steel before I pass them- it is easy to get out of practice.

Ordered new old stock diamond wheels on ebay as well

 

[stuckmotor]

I got a Drill Doctor. I got their top of the line model for the added versatility. It takes awhile to go through your drill bit collection but it seems to do a good job. I went through all my bits because, like you, I could never seem to find a sharp one when needed. If you want to trash your old bits instead throw them my way. I'll even pay reasonable postage.

Approximately how many randomly sized bits would you estimate can be sharpened before replacing the diamond grinding wheel?

 

[stuckmotor]

I don't recall ever seeing anyone dip a bit in water to prevent burning, in a Drill Doctor demonstration, and don't understand why not. Will someone please enlighten me?

 

[Yander]

My dad worked at a company that never sharpened their drill bits; just tossed them. He would bring them all home and sharpen them on a bench grinder. I don't know if the man ever bought a new drill bit in his life. I need to get a bench grinder.

 

[bdhsfz6]

It's that hour and 45 minutes to get to the hardware store that is the problem. You can also do lathe tools on a bench grinder, and it's right there. No gasoline required.

Very true, you use what you have on hand.

I usually keep a supply of 3/16" & smaller bits around. I order on line and it doesn't cost much.

 

[5030]

I don't recall ever seeing anyone dip a bit in water to prevent burning, in a Drill Doctor demonstration, and don't understand why not. Will someone please enlighten me?

Because the sharpening wheel turns at a lower RPM so it don't heat un the bit like a bench grinder tends to do plus the collet that holds the drill while sharpening conducts the heat away from the tip of the drill bit.

 

[ponytug]

I don't recall ever seeing anyone dip a bit in water to prevent burning, in a Drill Doctor demonstration, and don't understand why not. Will someone please enlighten me?

I was taught the "keep the blade cool" when I grew up, too. However, if the feed rate is low, there is no need, and the general idea turns out not to be true.

Longer story, with recent metallurgy analysis, it has been found that for many alloys (not all, especially for knives, not drills or chisels) localized heating of the metal, e.g. drill bits (and other cutting tools), doesn't affect the performance. As informal evidence, the number of folks who manage to sharpen their drill bits just fine on a grinding wheel, without using water.

I own a water cooled stone, which works great, but so does a grinding wheel and a 4 1/2" grinder for big blades. I personally have never found a metal edge that had a heat induced softness, but it is certainly possible that I missed it. I do like sharp knives; I think that they are both safer and easier to use.

All the best,

Peter

 

[repete]

Any folks from the Seattle area remember Boeing surplus in Kent? Bits by the pound.

 

[stuckmotor]

Because the sharpening wheel turns at a lower RPM so it don't heat un the bit like a bench grinder tends to do plus the collet that holds the drill while sharpening conducts the heat away from the tip of the drill bit.

Thank you! My only guess was that there might be a fan inside the device.

 

[bcp]

Any folks from the Seattle area remember Boeing surplus in Kent? Bits by the pound.

It was one of my favorite stores. Now Boeing sells their surplus in bulk by bid to businesses, I've heard.

Bruce

 

[Doofy]

Very timely thread. I received a Drill Doctor for Christmas about 10 years ago and forgot all about it. Time to unbox it and learn how to use it. I probably have a couple hundred bits to go thru. I really hate trying to use dull bits.

 

[bigtiller]

Because the sharpening wheel turns at a lower RPM so it don't heat un the bit like a bench grinder tends to do plus the collet that holds the drill while sharpening conducts the heat away from the tip of the drill bit.

agreed.
I just sharpened a 3/8 bit, changing the angle from 118 to 135. I squeezed the tip between my fingers and it was slightly warm, but a long way from hot.