# Drill Sharpening



## emjaiar (27 Apr 2022)

I’m one of those unfortunates who can’t sharpen a HSS drill to save their life. Has anyone any recommendations for a drill sharpening gadget that a. works, and b. is foolproof. I’ve probably bought most of them, but I thought it worth a try to see if somebody has something I haven’t seen.


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## Ttrees (27 Apr 2022)

I had an issue sharpening bits, for the most part it was due to not enough
time spent directly behind the cutting edge, even though I was heavily undercutting them.
Two things synergistic for me which made me get there.

Not holding the bit low enough on the bench grinder wheel, my grinder is on a low bench, and stooping lower more awkward.

Having a look at some bits, and copy... duh, you might be thinking?
Note some bits are ground with a smiley face shape to the flank/lands, and not tapering lands.
Getting that shape is more likely that you are removing material from directly behind the edge, 
instead of it just appearing so, which large under cut bits disguising material what's left.

Even though this video is of sharpening using a large angle grinder, the movement is largely the same,
I watched as many engineer youtubers sharpen on bench grinders, but this one is one of, if not the best I've seen for some reason.
I guess its just better video angles or something, but it sticks in there better than others.

AvE,(that incognito gold miner, engineer/frankentooler youtuber feller)


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## MikeK (27 Apr 2022)

I can't freehand sharpen a drill bit to save my life, so I use the Drill Doctor 750X. I wanted the 500X, but no one had them in stock at the time. I've been using the 750X for over 15 years with no problems and am still using the same diamond wheel. I don't bother sharpening bits smaller than 5mm, as they are inexpensive to replace.


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## emjaiar (27 Apr 2022)

I’ve looked at the drill doctor several times, but always think I could buy a lot of new drills for that sort of money. Mind you my blunt drill box is getting bigger and bigger


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## Spectric (27 Apr 2022)

If you place two hex nuts together, the angle formed is the angle you want your drill bits. Also once sharpened don't forget to back off the rear edge slightly.


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## J-G (27 Apr 2022)

Spectric said:


> If you place two hex nuts together, the angle formed is the angle you want your drill bits. Also once sharpened don't forget to back of the rear edge slightly.


That's close for general purpose cutting most Mild steel, but will give you 120° rather than the 118° that standrd 'Jobber' drills are when new. 

If you need a drill bit to cut Aluminium, Brass, Delrin, Nylon . . . the list goes on - most efficiently - then you need to take more care. I can't give you chapter & verse since I am an empiricist so re-grind my drills not to a prescribed angle/rake but to suit the specific application that is my current project.


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## Spectric (27 Apr 2022)

J-G said:


> That's close for general purpose cutting most Mild steel, but will give you 120°


Thats how my drills are used, the as new un-ground are for metal but once reground then they become general purpose, now I am into wood then no longer need specialised drills for metal. I was spoilt because I used to have them ground in a toolroom and had a set for harder material like stainless and a set for non-ferrous general but in those days none for wood.


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## Craig22 (28 Apr 2022)

My Dad used to sharpen drills freehand on a grinder. But then again he was a time served and indentured apprentice (7 years) at Vickers Armstrong on Scotswood Road near Newcastle, so perhaps that skill was not so surprising.

I suspect it is similar to knife skills with a professional chef. A mate was a pro chef, and when he was learning his trade he wasn't allowed to cook anything until he demonstrated sufficient skill in prep with a knife.

But I can't sharpen drills like my Dad to save my life! He's long gone alas, so he can't teach me.


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## Corset (28 Apr 2022)

i can sharpen by hand but it take s me a while to get the feel back if i havent done it for a time. I also have a drill doctor, i find the drill doctor gives good consistent results but if i have lots to do by hand is quicker. I cant say i regret the drill doctor its reliable. Bigger drill bits are expensive and almost all my drill are dormer etc bought second hand so very rarely sharp.


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## Sandyn (28 Apr 2022)

I'm half reasonable at sharpening drills, I look at a new one first, then try to copy the angels whilst fresh in my memory. I generally don't bother doing really small drills. I buy them in bulk.


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## Fergie 307 (28 Apr 2022)

MikeK said:


> I can't freehand sharpen a drill bit to save my life, so I use the Drill Doctor 750X. I wanted the 500X, but no one had them in stock at the time. I've been using the 750X for over 15 years with no problems and am still using the same diamond wheel. I don't bother sharpening bits smaller than 5mm, as they are inexpensive to replace.


I would add a vote for the drill doctor. It is pricey but it works. I also sharpen very small drills by hand but use a fine diamond lapping disc on a modified bench disc sander. This might help you as it removes a tiny amount at a time and you can see clearly if you are doing it correctly. Helps to hold small drills in a pin vice.


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## hawkeyefxr (28 Apr 2022)

I remember this from the toolroom as an apprentice. I was given a 1/2 drill and told to sharpen it, i was at it for around two hours before 'Harry' was satified. He then gave me a 1/16 drill, after about another two hours he laughed and took it awayand said we just throw those away and get a new one. 73 now and can still sharpen a drill.


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## J-G (28 Apr 2022)

hawkeyefxr said:


> 73 now and can still sharpen a drill.


I'm 80 and still sharpen drills down to 1mm Dia. (Carbide) - below about 3mm I seldom use anything other than carbide.


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## joethedrummer (28 Apr 2022)

hawkeyefxr said:


> I remember this from the toolroom as an apprentice. I was given a 1/2 drill and told to sharpen it, i was at it for around two hours before 'Harry' was satified. He then gave me a 1/16 drill, after about another two hours he laughed and took it awayand said we just throw those away and get a new one. 73 now and can still sharpen a drill.


,, same for me,, I worked with one of those Harries back in the 60s, at the time thought he was a difficult old b,,,,,,,,, but I"ve turned into one,,


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## clogs (28 Apr 2022)

save ur money and buy HSS with Cobalt.....really not much more......
once u've mullered them it dont matter....
Must have sharped thousands of drill by hand even the odd milling cutter...only sharpen down to 2mm now....only cos of eye sight.......lol....
It just takes practise and more practise....
when instructing a newbie, I tell em to buy 2 sets of drills from the likes of Lidil.....
keep one set new and sharpen the other....copy the new sets angles etc...
once ground try drilling with em.....u'll soon learn...


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## GLS (28 Apr 2022)

go to a car boot sale or similar pick up a bunch of knackered drills and keep practising on something it doesn't matter if you make a muck-up of. About 8 to 10mm is a good start size.


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## J-G (28 Apr 2022)

clogs said:


> only sharpen down to 2mm now....only cos of eye sight.....


That is certainly a limiting factor !


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## DBC (29 Apr 2022)

Amazed so many guys are sharpening drill bits. The only drill bits I have sharpened in the last 10 years are the augers from my brace and bit. And I hardly ever use them. I don’t sharpen drill bits and I don’t clean paint brushes. I justify this to myself by telling myself the replacement cost is built into my pricing and my time is best spent in production and quoting. However, if I’m really honest with myself I may be just inventing a commercial reason in order to avoid jobs I don’t like doing. Not sure.

I probably buy one of these at least once a year.





When I am fitting joinery I’ve made into a masonry background I tend to offer up a timber section to the wall and drill through using a timber bit to mark the wall by drilling 5mm into the plaster/masonry to mark out where I will drill later with an SDS bit. I can sometimes chew through 5 timber bits an installation doing this. Pretty wasteful I suppose. But I used to mark these out by predrilling and then using a sharp spike to mark the wall and occasionally it was hard to find the mark I’d made. Maybe I should be saving all of these blunted bits and donating them to you guys.


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## J-G (29 Apr 2022)

I would be ashamed to admit that as my 'practice' 

It is the attitude that pervades the minds of those that have no regard for resourses (scarce or not) simply because 'I can pass the cost on, so it doesn't affect my profit'. 

It also contributes to inflation !


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## MikeK (29 Apr 2022)

DBC said:


> I justify this to myself by telling myself the replacement cost is built into my pricing and my time is best spent in production and quoting.



When I requested quotes to paint the exterior of my house, one of the vendors provided an incredibly detailed list of the costs. He was at the high end of the "reasonable" zone for the quotes I received. One of the line items in the consumables section of the quote was €350 for Hilti SDS masonry drill bits. When I asked why he wanted to bill me for new SDS drill bits, he told me he had to drill holes in my concrete walls so he could insert anchors to attach the scaffolding and only used new bits for each job.

I told him if I'm paying for the bits, I wanted to see new Hilti bits when the scaffolding arrived and I wanted the bits when they were done with drilling the holes. He refused, so I rejected his offer. Had he not made the new bits a separate item in the quote, I would not have thought about it.


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## Phil Pascoe (29 Apr 2022)

One of my best ever buys is a 170 piece set, bought about 20 years ago. I've replaced 3mms and 6mms but other than that there are more bits in it now than it came with - everything acquired along the way gets put in it. If you're doing a lot of repair work the 1/2mm sizes are more useful than you'd first think.


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## Chief Sawdust Maker (29 Apr 2022)

I learnt way back in 1984 when I started my engineering apprenticeship
We had to sharpen everything from about 1/64 all the way to around 3" along with different point types
Standard, Flat Bottom Hole, Sheet Metal along with off centre sharpening on 3ft and 4ft long drills which we used to drill oil and grease ways in long shafts being off centre slightly meant that they didn't rub or bind 
It just takes practice practice practice as others have said I inherited my 8" bench grinder from my dad course wheel on one end finer wheel on the other keep a pot of water handy to keep the bits cool if it goes blue its no good grind it away and start again invest in a wheel dresser / flattener to keep the surface of your wheel flat 
I flatten Spade bits, Augers and Forstners by hand using diamond cards and files.
If you can try to have a multiples of the few of the common sizes you use when they blunt just put them in a box and when you have a spare hour with no pressure to get a job done sharpen everything in the box you will get better results as you arnt in a rush and trying to force a hole though a job
I have a few friends and neighbours that don't sharpen and throw them away so i ask them to throw them in my direction i do return a few shrp but the majority I keep, I haven't brought a common size metric drill in years
I run my own business and to chuck them away is like throwing money in the bin yes it take time to sharpen them but a short while when tidying the workshop or sat waiting for delivery is time well spent
Its a useful skill and and once you know how to do it it will stay with you


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## Bod (29 Apr 2022)

+1 for Drill Doctor, took a bit of getting used to, but does the job.
Eclipse 39 drill sharpeners work, all be it slowly, best used on nearly blunt, rather than well rounded.

Bod


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## DBC (29 Apr 2022)

J-G said:


> I would be ashamed to admit that as my 'practice'
> 
> It is the attitude that pervades the minds of those that have no regard for resourses (scarce or not) simply because 'I can pass the cost on, so it doesn't affect my profit'.
> 
> It also contributes to inflation !



You are right that I am not thinking about resources in relation to the paint brushes and the drillbits; although I do when it comes to items like timber and larger building/joinery materials. But I don’t know if I agree that I am passing some sort of unreasonable cost on to the customer. It is arguably cheaper for the customer. Drill bits in the box I copied in above are 22p each. And the throw away paint brushes from Toolstation are 30p each. Say I make you a casement window and come around to install it and have to trim one edge to make it fit well. The paintbrush I use to touch up the primer on the cut and a drillbit that may be used to fit it add up to 55p. That equates to around a minutes worth of labour. Cleaning a paint brush alone takes longer than that. Furthermore, find me a customer that is happy for you to clean a paintbrush on their property; where do you do this, in their sink, in their garden. I suppose I could be carrying some sort of solvent/water container around in the van to clean paintbrushes but I know this risks being upended somehow so I don’t.

So I plead partially guilty as charged. But I have to be competitive to survive and like it or not the same sort of commercial decision making is built into the price of the car you drive and almost all of the products you buy.


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## hawkeyefxr (3 May 2022)

J-G said:


> I'm 80 and still sharpen drills down to 1mm Dia. (Carbide) - below about 3mm I seldom use anything other than carbide.


1mm bloody hell!!! Thats a throw away lol


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## hawkeyefxr (3 May 2022)

joethedrummer said:


> ,, same for me,, I worked with one of those Harries back in the 60s, at the time thought he was a difficult old b,,,,,,,,, but I"ve turned into one,,


My Harry was a good bloke, took time to explain things. When using the surface grinder i wound the workpiece into the revolving stone going the wrong way. There was a bloody great bang like a shotgun and i buggered up the magnetic chuck, he just asked me if i was alright. great bloke.


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## J-G (4 May 2022)

hawkeyefxr said:


> 1mm bloody hell!!! Thats a throw away lol


At > £3 each it's not a throw away for me !!


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## Ttrees (4 May 2022)

@J-G 
THREE QUID, FOR CARBIDE????????
at what point does carbide get expensive?
I can say it's not cheap buying cobalt beyond say 8 or 9mm, locally around just under a tenner in Euros, if I only was aware of this sooner


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## J-G (4 May 2022)

Ttrees said:


> THREE QUID, FOR CARBIDE????????
> at what point does carbide get expensive?


I buy Carbide 'Micro' drills (1/8" shank) between 0.3 & 6mm cutting dia. (though it has been some while since I needed any) - most mid-range are ~£1 - £2 but extremes do get up to £6-£8 ish.


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## baldkev (6 May 2022)

I bought a cheap drill sharpener off ebay years ago, maybe 12 quid? Still working  similar to this








VOCHE® 70W ELECTRIC DRILL BIT SHARPENER 3-10mm HSS BITS SHARPENING MACHINE TOOL | eBay


Power: 70W. Mains operated, our exclusive drill-bit sharpener quickly sharpens blunt and dull drill-bits, allowing them to perform like new! Handles bits sizes from 3mm to 10mm (8/64" to 25/64"). Sharpens carbon steel and high speed steel drill bits.



www.ebay.co.uk




Its not expensive but ive done quite a lot of bits on it over the years.


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## johnnyb (7 May 2022)

as an engineering apprentice sharpening drills was very common. I'm laughing at trying to get 118 degrees instead of 120! the main thing is to have a clearance angle behind the cutting edge. the action on the grinder is a twist up. the rake is pre built into the wrist.
when your done twist the drill into your palm you can feel the edges. also try and grind a drill off centre to drill and larger hole( deliberately. it's not that simple. it should be but it's not....try it.
btw I use the side of a white wheel.


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## Dalboy (18 May 2022)

A little long winded but worth a watch This Old Tony

I can sharpen my drill bit freehand but the bits seem to be getting bigger before I can do so now as the smaller ones are not easy on the eyes. And just when I thought I cracked it I am now learning about negative rake grinds on them


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