Thread: Home made drill sharpener?

There's a current thread over at Madmodder.net that may fit the bill.
It's actually a build of Harold Halls' grinder table but towards the end of the thread, tit show with a drill grinding attachment..
Might be a bit of overkill just to grind drills but it does look good.

SS

Yep, I had forgotten about Harold Halls grinding table, and I have his milling book. That's my memory for you.

Had a squize at this unit, far too complicated, but like the principle.

[ame="http://www.youtube.com/watch?v=xRhBHOPqvRI"]YouTube - Precision Drill Sharpener / Drill Sharpener[/ame]

Ken

Apex machinery in Moorabin has one of those units in the showroom. I had a play with it and should have been impressed but wasn't. I think it has a little bit too much of the far east in it. They sold one to somebody who charges a buck a bit for sharpening which strikes me as a good deal. I hope to have about $50 worth of sharpening lifetime; certainly less than the effort to roll my own.

Greg

Originally Posted by snowyskiesau

There's a current thread over at Madmodder.net that may fit the bill.
It's actually a build of Harold Halls' grinder table but towards the end of the thread, tit show with a drill grinding attachment..
Might be a bit of overkill just to grind drills but it does look good.

A what now?

Actually fellas, you can get something similar from Carbatec. I think I paid $35 for mine, and I mounted it to the head from a $5 ebay camera tripod. It has three axes of motion and only takes a short while to make.

Greg

Ken that sharpener is simply a standard conical bit sharpener, save about $4K and just buy a drill doctor, it's doing the same thing!

Another vote for Harold Hall's table and drill grinding fixtures. It's actually just a very good grinder table that happens to have fixtures to grind end mills and drills. However both are ground using the multi-facet approach, arguably a much better drill profile.

Greg I actually use my Drill Doctor reasonably frequently, even at a buck a bit I'd probably go through that in a year or two at max. Having not had any easy way to grind drills until I bought that, what I found is that I'd persist in using a drill bit well past when it should have been sharpened. Now, as soon as they start to dull off I'll pop them in the DD, touch them up and it all becomes pleasant again. I'd definitely spring for something better than the DD if I could be sure it would be just as easy to use but could also be assured the results were consistent. The DD is "ok" but a bit "plastic" and I'm quite sure it doesn't grind the bits as well as is possible.

Pete

HI,I haven't had a Go at making My own as Yet, but I have certainly had a Good look at the Sterling Drill Grinder and the KEF Drill Grinder. A lot of Info can be gained from the Sterling Drill Grinder Website. Both of the Websites have Videos of their Drill Grinders. Here is the Links Welcome to the home of the STERLING Drill Grinder! and Manual drill / tool sharpener - max. ø 13 mm | KEF Slibette 6NE / N - Scantool Group .

I think the Stirling style grinders are basically just the little jigs designed to work on the side of the wheel, except the Stirling model is on steroids. I have one of the ebay style jigs and it certainly works "ok" for larger drill, but is a waste of time down in the sizes I'm always using. IIRC the action of something like the Stirling or the jigs is somewhat different to the grinder Ken showed at the beginning of the thread. A "proper" drill grinder will sharpen a better profile than the cheap jigs, although even the modified conical profile has now been surpassed by multi-facet drill profiles. Different manufacturers have their own unique names for them, but they're simply variations of the same thing from what I've seen.

There's a tremendous amount of information available on the net regarding this ... if anyone is interested here's one article I recall reading last year Drill Point Geometry an article by Joseph Mazoff for something most of is I think take for granted, there's a heck of a lot more going on than we give credit for. Personally I rate good, sharp drills as an enormous priority in my workshop, as it's extraordinary how often we use them, and there's a world of difference between seen 2 swarf chips easily curling away from the work, and a blunt bit making life miserable.

Pete

Sharpening drills freehand was one of the first things I was taught when I started my apprenticeship in 1961. I have sharpened so many since then,I think I could do it with my eyes shut (but I wont). "Practice" is the magic word. Russell

Russell this discussion comes up quite frequently on various BBs. I have a good friend who is very good at sharpening drills this way and I always admire his skill when I see him do it. I've tried in the past, but freehand sharpening was a skill I personally never perfected. The problem is that even though the drill may look well sharpened it's almost certain that one edge is not symmetrical with the other. That will drill a hole that is neither round nor straight. For 99% of the work that's probably fine, but when accuracy is required it clearly won't do. I think it's like my drill sets, I have some metric sets in 0.5 rises I use constantly. The main ones I use are still P&N, so not cheap rubbish, but I'd have no hesitation in freehand sharpening them. But then I have my "good" bits, they are in 0.1 mm rises and there's no way in heck I'd let them anywhere near the side of a bench grinder