Drill bits

[bigsnookmaster]

Originally Posted by domestictuner

i kind of have to laugh at some of the advice being given in here, so i figure i might as well chime in with my 2 cents.

it may not be "by the book" but it has worked for me, and how i teach my people at work. we drill 1/8" to 3/8" holes through anything from wood to 5/8" thick structural steel.

-the only thing air drills are good for, other then drilling holes in sheetmetal, is dulling drill bits. its a fine line between pushing hard enough to get the rpm down and stopping the bit from pushing too hard.
-there is a direct relation to speed and pressure. high rpm=high pressure, if you cant push hard then you have to turn the bit slower.
-quick change bits and a cordless impact driver, you are better off throwing your money in the trash, it is quicker and less frustrating.
-Get an electric drill. Push as hard as you can, as soon as the sound changes back off a little and hold the drill steady, its about through.
-If you aren't throwing off a continuous shaving you aren't pushing hard enough, or you're turning too fast.
-if your bit is squealing, its junk. Sharpen it or throw it away.
-titanium coated is just a gimmick, if you know what you are doing you cant tell the difference between a ti coated bit and a regular old black drill bit.
-cutting oil, for us, is more of a hassle then it is worth, some people swear by it, and use it for everything, we don't use it because of the clean up involved when drilling on a finished product, and it is just one more thing to have in the MSDS book.

we only use about 5-6 different size bits, but the way we look at it is, a couple of bucks a drill bit is cheap. if you are buying an index to replace a broken bit you are wasting your money. (I know a guy that has 3 or 4 bit indexes and probably doesn't have a complete one.) Buy a decent index once, then go to a construction supply store they have cases of bits you can buy one at a time should you need to replace one.

Lastly, the dewalt bits, with the smaller tips to pilot the holes are animals. they are also notched on the other end so if you are using a junk keyless chuck you dont have to worry about it spinning in the chuck. you may not be able to sharpen the bit once you dull it, but i just put the last one through 100 holes in 5/8 structural steel on a job, no oil, the same method i explained above. if i hadn't of slipped on the last one and noodled it, i would still be using it.

And this might be the wrong thread but you guys raving about your HF tools... are either sponsored or not using them much, we have broken every tool(a couple corded impacts, grinders, allen wrench sets) and destroyed a bit index from that place. there is a reason the tools are cheap there.

that said, flame away.

I'll second that on the DeWalt split point bits. I bought the whole set up to 1/2" a while back for 60 bucks at the Depot. Money well spent! If you really want an animal, find a machinists supply house and buy carbide bits.

[vectorit]

Well, I am all done.
The second bit I ended up getting, was a Milwaukee 5/8 HSS bit from Homie Depott.

This one, I had to drill three progressively larger pilot holes. It just didn't seem to cut like the Fastenal branded bit.

Thanks everyone for all the input!

On a side note:

I told my Dad all about this, and he just laughed about my issues.
See, he spent his younger years in the machine tool industry. His background is very high end machinist work, using very expensive tools made in Germany or Switzerland. He has all this kind of stuff down to a mathematical science, but it really didn't apply to me as a back yard mechanic.
He just cracked up about my experience with the snapped bit, saying that it was just a cheap shallow case hardened model. But then again I am not going to spend a hundred dollars on a hand made bit of the likes he use to use, so it was all kind of moot to me being that I had to shop for the best quality tool within my budget to bore maybe four holes.
Though it was fun to listen to an "old school" master machinist reminisce about ultra high end equipment, and the methodologies used in the process to cut all kinds of metal.

[mbgmike]

titanium coated is just a gimmick, if you know what you are doing you cant tell the difference between a ti coated bit and a regular old black drill bit.


Titanium Nitrated bits do not make much difference on a poor quality bit. It just makes a poor quality bit last a little longer. Our world has been swamped with poor quality stuff. Thats the biggest problem . Most start with low quality drill bits to save money and use a thin coat to save as well. Its expensvie to coat bits. The purpose is to make the drill bits last longer NOT drill better thats all. If you buy a quality coated bit they last a lot longer.everyone seems to go cheap and thats what starts all the rumors.The black oxide is just to keep chips moving in the flutes more freely otherwise they are the same bit if its a quality one assuming comparing apples with apples ie) same flute