Best way to sharpen a drill bit? SDS, Hammer, hss

[tonyjeffs]

I've just knackered a =A312 sds drill bit after one session, cutting a big hole in a wall for a wc waste, Usually, I dip a bit in cold water occasionally in such circumstances, but i got lazy and was impressed the way that SDS bits are slow to get hot.

Anyway Tips on sharpening drill bits generally? angle, ordinary hammer, SDS Many of the sds bits have a sort of nipple on the end, almost a bell or bobble hat shape - is that important ? I generally try and sharpen things dangerously with an angle grinder - a stone takes forever. Can I maybe buy a bit sharpening machine?

Where do I find the FAQ - I ought to know the address by heart. Thanks

Sony

SDS - I bought a cordless P drill from B&Q. =A350. It is quiet, determined, very good. The disadvantage is that the new battery lasts for about one 20 minute job. This worries me that after a few months, the batteries will need changing ever five minutes. So perhaps corded is better. Nevertheless, really good at the price, and a good intro to SDS which I must thank this group for telling me about recently.

[Dave Plowman (News)]

They can be useful for larger sizes - but most can only cope with up to about 12mm. However you could use the grinding wheel part and do it freehand.

Fact of life with any power hungry tool. The same applies to circular saws. Cordless versions are only really worthwhile if you have no mains available - or where it would be inconvenient to run it. With SDS such a thing might be fitting satellite dishes for a living. For most DIY mains is better.

[Dave Liquorice]

Sounds like you are using a bad technique or you where drilling somethin= g

*very* hard. You don't need to push hard on an SDS drill like you do wit= h an ordinary hammer drill. Push enough to stop the bit from chattering round or in the chuck but there is no need to lean on it. The cutting co= me from the heft impacts that the SDS mechanism delivers.

I wouldn't do that to any drill, heaven knows what the thermal shock wil= l do to the tempering...

Mine don't, at least not that I have noticed. They all seem broadly like= the ends of two cold chisels joined at an angle.

Martek, if it's still about, for small HSS and ordinary masonary drill with the correct stone.

[The Medway Handyman]

I'd take the bit back & whinge if I were you, even a cheapo should last one hole.

I can't be arsed to sharped drill bits, a new bit costs less than the time it takes to sharpen it.

£50 is cheap for a cordless combi drill. I think you got what you paid for. When you pay the extra for DeWalt/Makita/Bosch you get much better quality batteries & chargers.

[meow2222]

bench grinder best, angle grinder can also be used if you go easy and give it plenty of time to cool between short sharpenings.

Either its carp or you were pushing it much too hard. You should get far more use time out of a mcuh cheaper tool than that.

For drilling wood the following bits use far less energy per hole:

[RW]

Anyway Tips on sharpening drill bits generally? angle, ordinary hammer, SDS Many of the sds bits have a sort of nipple on the end, almost a bell or bobble hat shape - is that important ? I generally try and sharpen things dangerously with an angle grinder - a stone takes forever. Can I maybe buy a bit sharpening machine?

Where do I find the FAQ - I ought to know the address by heart. Thanks

Green Grit wheel or a diamond wheel made for the purpose.

on a proper bench grinder. Gentle and slow sharpening with LOTS of dipping in water (Shock to carbide will be insignificant) to prevent the braize from releasing the tips.

*Never* grind the sides of the carbide. Follow the original shape if there's any left. If not then the front edge grind back at the regular 59 deg angle from centreline (Much the same angle as a normal drill) and just take off the front leading edge face by about 1 to 2mm to give the drill a negative approach. Take care to keep both lands equal or it will lead off from centreline when in use

I used to "refurbish" SDS and other drills in the same way while in plant hire and they worked fine.

[dave]

Yeees there's something fishy about that alright.

[tonyjeffs]

Thanks for the tips. Might've misrepresented my use of the drill bit. I used it to cut out a 4" dia hole by drilling at half inch spaces around the edge through pressed engineering brick, so it did take a beating, and I know now that i was pushing too hard.

...........

I needed exactly 6 x 3m lengths of copper pipe B&Q =A339. But a pack of 10 is =A340 so I got that instead. I'll leave the four spare on the garage roof for a few years until they're corroded enough to bin. ;-)

[meow2222]

For hard work use corded. More power & endless capacity

NT