Twist drill sharpener/ing

[Shedendman]

A really basic and i mean basic rule to begin getting the drill to cut is the leading or cutting edge must be above the trailing edge and not visa versa...even a very rough grind or sharpen using this rule will allow the drill to cut and drill a hole.

Yer,its getting that spot on that keeps reminding me

 

[Shedendman]

I now remember way way back seeing my dad hone one up using a fine file,a little scrape here one there and it would drill through anything,but as a lad back then who didnt pay any attention i'm damned if i knew the secret

 

[nickk]

Good tips @roofman ,but also to add grind from the leading edge,then roll back to trailing edge to help take the heat away,and avoid getting a burr at the sharp end,also quench often else you’ll take the hardness out and it won’t cut,keep the length of each cutting edge the same,and the bit will cut accurately and to size.
I’ve been lucky self taught and find it a doddle,used to grind them for the whole factory,back in the day.

 

[Shedendman]

I'm ok with say 8mm and upwards(just),before then,its sod it buy new ones

 

[Seadog]

The knack is getting the angles and cutting edge the same, apart from rolling the drill off of the wheel.

 

[Memmeddu]

The hardest part is cut under the chiesel point ,to make it drill without the pilot hole

 

[roofman]

I treat my drills like wood chisels and every 2nd or 3rd time i use them i just flash them over the grinder to put a nice keen edge on them, takes about 15 seconds and makes the world of difference when using them

 

[roofman]

The hardest part is cut under the chiesel point ,to make it drill without the pilot hole

easier using a center drill 1st to pilot then the importance of that point is taken off you when putting an edge on them till you get better at it

 

[Ali]

I don’t like to point at YouTube vids, but this is very good. To demonstrate how a drill cuts he goes right back to basics, and actually makes a basic drill bit

 

[Memmeddu]

I was reading about but I've not understood which is the best angle
118° is the standard
But there are other drill bits which have
134°
140°
Up to 180°
All of them have 12° cutter relief angle
The drill bit I've hand sharpened has roughly 135° and 13°
It does cut very well
So I don't know
I would like to understand which is the difference between the various angles
Maybe different materials etc

 

[waldershelf]

I'm OK sharpening drills over 1/4" or so on the bench grinder but for smaller drills I have a cheap electric sharpener, Lidl I think, that does the job.

 

[waddycall]

Thinner material needs a shallower angle to stop the drill pulling itself through before you have a round hole.

 

[jordan1]

I was reading about but I've not understood which is the best angle
118° is the standard
But there are other drill bits which have
134°
140°
Up to 180°
All of them have 12° cutter relief angle
The drill bit I've hand sharpened has roughly 135° and 13°
It does cut very well
So I don't know
I would like to understand which is the difference between the various angles
Maybe different materials etc

If it cuts 'very well' be satisfied with it.

 

[Wedg1e]

I really really need to learn to sharpen drills. I believe it's a black art frankly. Especially on a bench grinder.

YouTube here I come.

It is a bit. I can get down to about 3mm with a big magnifier, good daylight and a fine grit wheel, and if push comes to shove I've monkeyed new edges onto 1.2 and 1.5mm with the diamond wheel, but even that has a midgie's of runout. With my reading specs I'm going bong-eyed trying to do anything smaller than about 8mm
I wouldn't claim any sort of accuracy for edge length, angle or anything else but if you need a hole in something, a drill that cuts somehow is better than one that cuts nohow.
If you fancy a challenge, try doing them freehand with an angle grinder. For added smugness, throw in a disbelieving project manager who wants to wrap up for the day because all the drills are blunt (EDIT: Ah, I see waddycall has beaten me to the angle grinder bodgery )

 

[mtt.tr]

It is a bit. I can get down to about 3mm with a big magnifier, good daylight and a fine grit wheel, and if push comes to shove I've monkeyed new edges onto 1.2 and 1.5mm with the diamond wheel, but even that has a midgie's of runout. With my reading specs I'm going bong-eyed trying to do anything smaller than about 8mm
I wouldn't claim any sort of accuracy for edge length, angle or anything else but if you need a hole in something, a drill that cuts somehow is better than one that cuts nohow.
If you fancy a challenge, try doing them freehand with an angle grinder. For added smugness, throw in a disbelieving project manager who wants to wrap up for the day because all the drills are blunt (EDIT: Ah, I see waddycall has beaten me to the angle grinder bodgery )

Drill sharpening is one if those things i picked up really quickly.


Below 1.5mm drills i use a diamond stone.




Before

 

[Wallace]

When you get the hang of it try a left hand drill.

 

[Parm]

When you get the hang of it try a left hand drill.

Do you need a left hand grinder?

 

[Ton-up]

My work colleague grinds RH drills LH!,

 

[Memmeddu]

My work colleague grinds RH drills LH!,

So he practically use to destroy drills

 

[mtt.tr]

When you get the hang of it try a left hand drill.

Try carving chisels.