Best drill bits? (1 Viewer)

[Bailey58]

I've got a few more drilling jobs to do when we go out to the Faroes and wonder what other folk use for drill bits. I had to drill about 180 10ml holes in very hard steel posts for a new fence a couple of years ago and even with cutting oil went through HSS bits like anything, even progressing through the sizes of bit. Bought some very expensive ones locally but can't remember what they were, titanium, cobalt? I plan to take some with me so suggestions, and some free samples, would be welcome.

 

[Allanm]

None of the ones I have bought in the last 45 or so years! I'd be interested to know what people recommend too.
Allan

 

[DP+JAY]

That will be Cobalt. If you find a free/very cheap source let me know.
http://www.toolstation.com/shop/sd1...tdrill&pmt=b&gclid=CKWQ8vmOob4CFennwgodujgAFg

This is the best one I know.

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[Wildman]

fence posts and bed frames tend to work harden and HSS drill are no good unless you run them very slow with cutting oil. The titanium (Gold coloured), come in different qualities, from thick to thin plated, get the best and they will do the job. When selling at a show they always make a point of drilling through a file. So should do the job for you.
However Cobalt are even better
Cobalt Drill Bits


Fully ground, high performance cobalt steel drill bit, manufactured with 5% cobalt.

For use on alloy & hardened steel, cast iron and titanium.
Broken Link Removed

 

[pappajohn]

dont forget speed is as important as quality.

A large bit at high speed will overheat and blunt in no time.

 

[jonandshell]

FYI theres no such thing as a drill bit in engineering. Carpentry maybe, but not engineering!
It's simply a drill!!!

I agree that cobalt is the way to go, observing the correct cuttimg speed for the material being drilled of course!:thumb:

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[wasp]

if you drilling 10mm holes I always use a pilot drill that usually helps :thumb:

 

[pappajohn]

FYI theres no such thing as a drill bit in engineering. Carpentry maybe, but not engineering!
It's simply a drill!!!

I agree that cobalt is the way to go, observing the correct cuttimg speed for the material being drilled of course!:thumb:

agreed, bit try that in a diy shed.

I'd like a 10mm drill please.....the first thing they'll try to sell you is a drill with a 10mm chuck.

We use a lot of hole cutters and watching the young guys using a 100mm wood saw at the fastest drill speed is a sight to behold....if you can see the cutter for smoke.

Their reckoning....its going fast so it must cut quicker oh:

 

[Sandancers]

Do you have to drill the posts in situ ?

If you can pre-drill them on a pillar drill you can then set a more accurate speed and pour the cutting oil on. That way the drills would last much longer. You could also re-sharpen them a few times on an angle grinder.

Basically weigh up the cost of buying a few top-notch ones against lots of poor quality ones.

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[Bailey58]

Do you have to drill the posts in situ ?

If you can pre-drill them on a pillar drill you can then set a more accurate speed and pour the cutting oil on. That way the drills would last much longer. You could also re-sharpen them a few times on an angle grinder.

Basically weigh up the cost of buying a few top-notch ones against lots of poor quality ones.

The posts were an old job, just asking for future reference.

 

[tonyidle]

The only thing you can do to make drills last is to never put them in a pistol drill .

At that drill size you need no more than 500rpm but where a pistol drill falls down is the inability to maintain a constant pressure. As soon as the drill rotates without cutting the material under the bit is work-hardened making the next cutting rotation more difficult.

Hold the pistol drill so you're pushing directly in line with the chuck (use your little finger to operate the switch) and if possible enlist a helper to brace yourself against.

 

[Landy lover]

Only ever use cobalt these days but even then you do find different manufacturers are different qualities.

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[Tootles]

I get through quite a few, and so I buy cheaply.....(not that cheap, but you know what I mean). We were in B&Q, and I saw a large type set for around £25.00. That was eight years ago, and even though I have re-sharpened them a few times, they are still giving good service. Like anything else, a 'good name' dosent mean a good product. The Bosch ones I bought were cr*p.
Don't bother with the fancy stuff, just good looking high speed black drill bits. :thumb:

 

[Gooney]

I get through quite a few, and so I buy cheaply.....(not that cheap, but you know what I mean). We were in B&Q, and I saw a large type set for around £25.00. That was eight years ago, and even though I have re-sharpened them a few times, they are still giving good service. Like anything else, a 'good name' dosent mean a good product. The Bosch ones I bought were cr*p.
Don't bother with the fancy stuff, just good looking high speed black drill bits. :thumb:

I bought a boxed set of Bosch drills from B&Q, the bloody things bent when asserting pressure on them

 

[Tootles]

That's what happened to mine!! They were in a grey BOSCH box, really dump! :Angry:

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[daveandsan]

Any good quality hss drill will do the job you don't need titainium coated or cobolt. Run drill about 400 rpm max and use cutting oil.
If possible drill a pilot hole 3 to 4 mm maximum, any bigger and the 10mm drill will dig in. :thumb:

 

[phil1946]

http://www.idealworld.tv/SearchGridView.aspx?fh_location=//idealworld/en_GB/$s=drill%20bits&gs=drill%20bits

I bought some of the above when they had them on offer at half price.

Not cheap but they have hex shaft and a ten year guarantee that I know they honour.

I bought something else (a grind/cutting disc pack of 2) from the same firm over 10 years ago with a lifetime guarantee and free replacement when worn out and got new ones for the cost of postage last year because they had worn down in size.

 

[scotjimland]

what a boring thread..

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[steviebouy]

I am currently using Dormer A100 drills. Got a set cheaply on eBay and am replacing individually as I ruin them. For some reason I used to be a demon sharpener when I was younger but have lost my touch. Eyesight maybe? You will find many different grades to suit different jobs. Check the Dormer website. Best I've used for years. Good advice about using a pistol drill, I always wondered why drills cut so much better in a pillar drill.
Cheers, Steve

 

[Bailey58]

what a boring thread..

Ah threads.Thanks for reminding me Jim, I was gonna ask about screws next!

 

[Ridgeway]

Always managed with HSS drills and a bench grinder. I sharpen my drills often and can't see how we can expect a cutting tool to always remain sharpoh:

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[steevie]

Consider a sharpening tool. You can get one that sits next to your grinding wheel for very little money, and does the correct angle every time, or a dearer specific machine that sharpens all sorts of stuff. You can run them from a smallish inverter from your vehicle if need be. I too have lost the knack of sharpening drills as I have got older, but my sharpener for the grinding wheel cost under a tenner. As said, any cutting tool will need occasional re sharpening.