drill bit sharpening

I once tried an electric can opener with built in sharpener. I'd rather kill myself than sharpen my tools on it.

NT

Yes, the Lidl free standing one is not good. It can't cope with small drill sizes and isn't much better on big ones.

Not good. Any machine which could sharpen a drill properly without any skill from the operator ain't going to cost just a few quid.

They tend do sort of work with large drills, but not with small.

Link doesn't work for me but no matter. I would think that an angle grinder is hardly the tool for the job, in fact a ruddy dangerous way of going about things. I have a gadget powered by electric drill for sharpening drill bits from 1/8 to 1/2". Fiddly to set up and fiddly to use. Never do less than 20 bits in a run. By the time I've done 10 I'm getting the hang of it, do the batch, then go back and redo the first 10! I think Sharpenset have a drill sharpening attachment for their machines. Rather expensive though. I have a Sharpenset dating to the early 1960's, slightly modified. Wonderful for knives of most kind, plane blades and woodworking chisels. Unfortunately my machine is too old to accept the more modern attachments and I'm too old to even consider replacing it. Towards the bottom of this page:

I used to be able to sharpen drills from 1/8 up on a bench grinder. AD has got the better of me alas. Nick.

Unless you're doing production line quantities of drilling, just buy your most used sizes by the dozen. You can buy a lot of bits for the cost of a decent sharpener!

I was just thinking along the same lines. Back in the day I bought a so called drill sharpener, it was rubbish and could be dangerous when things went wrong. I ended up buying new drills when I needed them. Brian

New drills straight out of the box have an edge but they aren't sharp.

I have a Martek drill attachment sharpener bought many moons ago and the difference betwen a new drill and a sharpened one is very noticeable. Like many of the budget sharpeners it's not very good on drills less than about 1/16", main beacuse they are a bit flexible.

Yes - I've got one of those too. But a PITA to set up and use, but works better than any other I've tried. An all in one of the same quality would be the best compromise. But haven't seen one.

I tried one of the ones which clamp to a mains power drill attachment boss, and it was complete rubbish. But I thought the recent Lidl "stand alone" version of the same thing was not too bad. Not much good for < 3 mm but sort of OK for bigger drills.

Looks a bit like this (just the first which came up in google)

They don't seem to be available in this country anymore. Fiddly I don't mind as long as it's not much worse than setting up for a tungsten carbide chain. I already sharpen brad point bits freehand on the bench grinder at work.

I suppose I'll revert to the idea of using a bench grinder but are the attachments for these any better?

AJH

I've never seen much upside in attachments. I do mine freehand. If you get one wrong it's not hard to redo it next time.

NT

I found those jigs rather hit and miss, but for those who do have a bench grinder, there is an older 2 part introduction by Graham Meek at:

and:

After a lot more experiment he recently wrote a 2 part article called "Perfectly Ground Twist Drills Every Time" for Engineering in Miniature which is in the current (March) edition and in the April one.

Alan

I haven't gone on to read those articles, as of yet.

However, while I love the idea of the 'perfect' jig for sharpening anything, when using the odd jig, I never did much better than my hand held technique. For me, I believe it is more to do with my poor eyesight, as well as presentation and body posture. When wearing glasses the outcome was a fair bit better.

Do the jigs for sharpening drill bits take care of all aspects of the process ie, centralising the mid point (Chisel edge) so that both cutting edges(Lips) are equal length? Do they take care of the relief behind the cutting edge?

We were having trouble cutting locating holes in timber for some dowelling we had. The bits were either too small or too big. Looking about the compound for a right size we came across a guy in his unit who measured the dowel then proceeded to take a little more off one edge than the other resulting in a shifted centre.

The drill now being exceptionally sharp it cut a wider hole than the drill bit's width. I Marvelled.

...Ray.

Which in your case was an advantage.

My problem is that doing the bits freehand I produce the same result, one cutting edge longer than the other, which means my 8mm drill starts cutting a 9mm hole and was the reason for my initial posting.

Similarly my post about induction hardening was me wondering if I could re harden cheap drill bits by very quickly heating the edge and allowing the mass of metal behind to quench it.

I do remember seeing an article about needle making as a cottage industry where the finished needle was heated in a candle flame before being quenched in a potato.

AJH