Brendan2010
New member
Can anyone recommend a fool proof method for sharpening drill bits without having to spend a fortune?
Drill bit sharpening
- Thread starter Brendan2010
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porker
Established Member
I've always sharpened by hand on a grinder. It takes a bit of practice but I've been happy with it. Plenty of tutorials on line. Caveats being that I have only done ordinary twist drills and spade bits not lip and spur for example. Also small bits get progressively more difficult so under about 3mm I treat as disposable.
You can get drill sharpeners that fit a drill but I've not used one.
You can get drill sharpeners that fit a drill but I've not used one.
One answer is to use old style auger bits or centre bits and sharpen them with a file.
But I guess that might not be what you meant. Care to tell us a bit more about what you want to achieve, what sort of bits, what kit you have already?
But I guess that might not be what you meant. Care to tell us a bit more about what you want to achieve, what sort of bits, what kit you have already?
That would work
Established Member
Same here, by hand is easier than you may think. The most important thing is to make sure that you end up with a clearance angle away from the edge. .. so in other words a slight slope down from the cutting edge when viewed side on. Also must be kept with the point central. Interestingly you can make a twist drill bore a knats willy oversize in metal if the point is off centre.
Phil Pascoe
Established Member
Foolproof is perhaps asking a bit much
but I recently re-learned how to do it freehand on the grinder and I've had very good luck with it. See previous thread for more info.I know this was a rhetorical question but I can provide some reasons:
- you can get some bits sharper than they came from the factory;
- you can customise the geometry to better suit drilling into wood (or other materials);
- it allows you to make use of old, blunt (even broken) bits from the car boot that cost 10p each.
It might help if you identify what types of drill bits you will be sharpening. I use the Drill Doctor 750X for all of my HSS and cobalt twist drills and think it's about as foolproof as can be. There are plenty of people who complain about the Drill Doctor, but it has never failed to work for me.
Like Porker said, I don't bother sharpening twist drills smaller than 3mm or 3/16-inch. These are inexpensive enough to toss when they are dull or break.
Grinder for larger bits and a diamond hone for smaller. Just follow the profile that's already there (if smaller bits are split, they can be tricky).
Even though you can sharpen anything, it's worth getting good western-made bits to make the sharpening efforts worthwhile.
Even though you can sharpen anything, it's worth getting good western-made bits to make the sharpening efforts worthwhile.
Cheshirechappie
Established Member
Might be worth an interweb search on 'Tool and Cutter Grinding Services'. Many such companies offer a mail order service, and are often not too expensive (though that may depend on what individuals define as expensive). Might be worth the cost for better quality tooling; maybe not so much for the budget end of the market - in the latter case, scrap and replace with new, or touch up on a bench grinder.
Can you define that for a novice I'm fed up of buying drill bits and they go dull or end up breaking due to having to press too hard. I'd gladly pay for good quality if I knew what it was and where
Glenn
Trevanion
Greatest Of All Time
What are you drilling? For most general metalwork I have a couple of sets of Milwaukee Thunderweb 1mm-13mm bits that are excellent, then I have a cheaper TiN set with the cutting edges dulled down to a neutral angle for brass drilling. There are a few odds and sods of cobalt and carbide bits that I've bought for in-particular jobs in certain materials but I wouldn't run out and buy a cobalt or carbide set.
For wood, I've got a set of Heller brad points which are OK, I touch them up on the grinder ocassionally. Anything over 10mm I like to use Irwin spade bits.
Been mainly drilling into the walls of my house and shed. I recently bought a Bosch set off amazon and they too are pants. I may have technique issues as well tbf I'm a 250kg bloke and may exert too much pressure so I've been told before
Trevanion
Greatest Of All Time
Well, at risk of sounding like I'm trying to teach a grandma to suck eggs... but if you're drilling into any masonry you'll need a masonry bit which looks a bit like a regular bit but they have a hunk of carbide brazed on top, they need to be used with a drill that has a hammer mode to actually work otherwise you're just grinding the wall with the bit and you'll get nowhere.
Cheshirechappie
Established Member
I'll try.
For drills, makers such as Dormer, Fisch, Famag. Their products are usually quite pricey, because they tend to use better grades of steel (M2 or M42 High Speed Steel) and manufacture to closer limits than the budget lines.
Bear in mind that all drills will go dull with use, and will go dull quicker with abuse. If you push them too hard into whatever you're drilling, they can't clear the waste fast enough, so clog and bog down. The bog-standard jobber twist drills are not designed for drilling wood; they will, but not as fast as some people think. Lip and spur drills do a bit better, but still benefit from being allowed to drill at their own pace - don't lean hard on them, and if the do slow down, withdraw the drill and clear the waste before advancing the hole a bit more. Even fairly cheap jobber drills will do good service in wood if allowed to cut at their own pace and not forced.
Phil Pascoe
Established Member
woodbloke66
Established Member
Many years ago when I was a Plessey apprentice, an old, time served engineer showed me how to sharpen a jobber drill by hand using a standard grinding wheel. When you see how it's done, it's the easiest thing in the world! It takes me about ten seconds (or less) to grind a HSS drill bit so I've never bothered with any sort of jig - Rob
Adam Pinson
Established Member
johnnyb
Established Member
my technique to achieve the clearance is its a twist with the fingers and a tiny tilt. use a big drill to practice. only take a tiny amount off. check it by drilling wood as its soft. I've found its not easy to alter the hole size by offset grinding the tip esp in wood. my point being don't worry about tiny discrepancies.8
I do the same "rolling clearance" technique, seems to work fine, I might try the method in the video though.
I also have not found too much of a problem if the centre isn't perfect, but you can get some wobble when drilling. Whether this matters depends on what you are drilling, what you are drilling with and how critical your hole is. For general purpose stuff it doesn't worry me, when working on the lathe or doing critical work I only use new factory ground bits, that is because the work is worth way more than the drill bit.
