I need to get some better drill bits for cutting through good German steel. Can someone recommend a basic set of bits available by mail order? 3/8" shank maximum for my handheld drill, and I need up to 1/2" bit size.
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"If the sky were to fall tomorrow, the tall would die first."
-Dr. Paul Forrester
Do I LOOK like I need a psychological evaluation??? -
McMaster Carr will be your best friend -
Any good High speed steel bit will work well for you. Just remember when drilling though metals GO SLOW, with the rotational speed and just enough pressure to keep the ribbons coming up, keep the lube poured to it as well. A cool bit is a sharp bit.
Northern tool used to have decent HSS bit set for about a 100 bucks that had every size you could want.
Seems pricing has gone up a little bit, as this is the set I have.
http://www.northerntool.com/shop/tools/product_579_579
But this set would prolly do for most of your practical applications and give you a little better service life out of them
http://www.northerntool.com/shop/too...duct_7899_7899The American Republic will endure until the day Congress discovers that it can bribe the public with the public's money. -Alexis de TocquevilleOriginally posted by Fusion
The Desire to Save Humanity is Always a False Front for the Urge to Rule it- H. L. Mencken
Necessity is the plea for every infringement of human freedom. It is the argument of tyrants.
William Pitt-Comment
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Buy some cobalt bits, american made if possible. i cant imagine using anything else anymore.Last edited by LJ851; 07-04-2013, 04:46 PM.Lorin
Originally posted by slammin.e28Comment
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Go to an estate sale/ tool auction/ flea market and find the oldest most complete USA, Austrian, German etc. made set of HSS bits there. They truly do not make them like they used to. Practically anything you buy in Lowes or Home Depot or any big box store now will be made in China. I just bought an entire large drill bit index of Austrian made HSS bits for $30 at an estate sale. They cut better and faster than my brand new Wurth HSS bits.Comment
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keep the ribbons coming up
Bingo - mrsleeve hit the nail on the head. The microscopic front cutting face of the tool needs to be constantly removing material. If not, you're dulling the tool, cause too much friction.
That leads to heat build up. And not - "oh no!!! the bit is hot when I took it out!!!!!" - the temp of the tool steel in general isn't the issue. That's not the problem. Tool steel can get really, really hot before any of it's properties change. People think that steal changes it properties at like 200-300 degrees. No so at all.
What's the problem is the tiny, tiny cutting edge of the bit. Locally, on that microscopic edge, it can get so hot the cutting edge melts - and you'll end up with a dull tool, and a poor cut. It's a "Force=pressure x area" thing.
This video is all about milling - admittedly kinda over kill for this thread (Not trying to be a know-it-all, I'm not) - but it's good general knowledge - and it's helped me a lot recently. Weather you're milling or drilling, it's kinda the same deal.
And for even more over-kill engineering porn....
Last edited by george graves; 07-05-2013, 02:55 AM.Originally posted by Matt-BComment
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What sort of cutting oil do you guys use?
I usually hit it with WD40Comment
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Shit soap would be better than that. WD40 isnt a lubricant, its a solvent. Just get some water soluable cutting/drilling oil from your local hardware box.
And like said, a cool bit is a sharp bit. Most people ruin bits in 30 seconds by putting it on high speed, not lubricating and holding the trigger.Im now E30less.
sigpicComment
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The best tips ever taught to me regarding drilling metal: SLOW speed as already mentioned, and annealing the metal beforehand. I do the latter by heating with a plumber's torch. Not cherry red, but hotter than you would want to touch. Takes a bit of experimentation.
Not always possible depending on location, and obviously not a necessity, but I get the best results after applying just the right amount of heat.'84 318i - Lapisblau/Schwarz (in cryosleep)
'06 330i - Titansilber/SchwarzComment
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Wow, lots of good information here. What about this set:
"If the sky were to fall tomorrow, the tall would die first."
-Dr. Paul Forrester
Do I LOOK like I need a psychological evaluation???Comment
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diamond tip drill bitsM30 is God's motor.....but Jesus drives an M60'd car -slammin.e28Comment
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Browntool.com under cutting tools for anything your heart desires.
There's nothing worse than a shitty drill bit.Originally posted by priapismOriginally posted by shamesonComment
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