Drill bit Sharpener

[Cornish Rattler]

Hi guys

Can anyone recomend a decent drill bit sharpener please 🙂

[muddy]

upside down grinder and some practice.

[jason110]

I’ve got a cheap bench grinder from Aldi. 

[Blanco]

In my experience drill bit grinders, certainly the high street ones are of little use.  There are some more sophisticated machines at  around £500 that will do a decent job, but at that sort of money you might as well get a more useful and more capable D-bit grinder. A bench grinder with a fine cut wheel, a pot of cooling water and a bit of practice will be much quicker, much cheaper and you will learn to appreciate what matters about the shape. Lots of stuff on YT on it, and quite a few self-build style guides/alignment aids you can have a go at, but once you get to a certain point most people freehand sharpen with success. You learn to stop and redo one that isn't cutting straight away. Much better to spend the difference on drill bits then when you do have a sharpening session, you are getting multiple goes at once and a better feel for it

[landroversforever]

Best bet is a bench grinder with a decent wheel in it. All of the specific sharpeners I’ve used have been rubbish. 

[Escape]

I've bought a cheap one a couple of months ago, but haven't used it much. The results seem to be hit or miss, which is annoying as that's what I was getting using a bench grinder as well. I'd hoped a dedicated sharpener would make it an easy job and as said would lead to a lot less time wasted using blunt drills. Even if the result is not perfect. So far that has not been the case. I'll have another go this week, now that this thread has given me a wake up call.

[Cornish Rattler]

2 hours ago, Escape said:

I've bought a cheap one a couple of months ago, but haven't used it much. The results seem to be hit or miss, which is annoying as that's what I was getting using a bench grinder as well. I'd hoped a dedicated sharpener would make it an easy job and as said would lead to a lot less time wasted using blunt drills. Even if the result is not perfect. So far that has not been the case. I'll have another go this week, now that this thread has given me a wake up call.

I've just bought a Drill Doctor and out of about 150 bits i only had 1 that wouldn't cut ( point ended up blunt ) but i had a few of the same bits so just bined it and not all bits were blunt but went through all the bits so all sharp now, it will also do SDS drill bits so had ago at doing a couple that i had and see how they are when my SDS drill arrives 🙂

Edited October 18, 2021 by Cornish Rattler

[JohnnoK]

If you've got the money, TORMEK is the way to go.

[De Ranged]

I've got a cheap copy of the "Drill Doctor" I find it does a servicable job on 1/2" or less, there isn't enough rake back so I find they go blunt quickly, I have a vertical grinder that I have used for yrs to freehand sharpen 

Now even with good glasses I can still mess up a sharpen, you can spot this because the swarf will be different one flut to the other when used in a fixed drill ( press or the lathe), so what I tend to do now is to use the Drill Doctor to even out the drill and set the cutting edge, then I grind the back off similar to a split point grind..... and continue to freehand till I get that bad swarf 

[sean f]

I have never got the hang of sharpening drills free hand, I can normally get there in the end but not quickly so I got one of these.

It started as a Chinese "G3" sharpener and will do from a couple of mm to 32mm it puts a good edge on but the drive motor died so hence got modified to run with a new motor and a belt.

For slightly blunt drills it only takes 30s or so to sharpen them and with a bit of care you get good result, primary edge, relief cut and split point, with proper knackered drills as below it takes a bit longer and I normally do free hand them to somewhere close first.

 

I promise it wasn't me that did this to the drill, the result of to much RPM and not enough cooling.

After a bit of work it got to this.

For big drills I use this.

It's from about mid 1950's and has a weird cut action but works really well once yet get the hang of it, the drill is rotated and the grinding wheel then spins but also moves across and in and out to put an edge on, the grinding wheel and the chuck need to be lined up and in sync which took a bit of experimenting to get right. It will do up to 3" drills, I have done quite a few around the 2-2 3/4" range and the bigger ones take a bit longer but work fine. It doesn't do a split point of any type so if you wanted one you would have to do it manually but mostly with that sort of size drill I am using them to open out a pilot hole I have drilled with something smaller anyway.

[Bowie69]

That looks very like an engine valve grinder....

[mickeyw]

On 10/17/2021 at 8:01 PM, landroversforever said:

Best bet is a bench grinder with a decent wheel in it. All of the specific sharpeners I’ve used have been rubbish. 

And the requisite dexterity and understanding of drill point geometry .

Where I did my apprenticeship we had a Dormer drill grinder, which made a beautiful job of big drills. Anything under 13mm I'd do by hand.