Drill Bits

[Geo]

Hi all,

I need to get a set of drill bits to replace those that wandered off a divisional office site last year.  Teaches me for taking my stuff to work.  Mainly for metal use.  Both in a drill press and hand held.

What type? (titanium, steel, unbreakium)  Where to get them?  Individual bits and sets with index.

Thanks for the info.

Geo

[McRat]

Best multipurpose bits are American made HSS (High Speed Steel) bits for drilling metals.  Cobalt is the cost effective for alloy steels where you need to get good life, and carbide is the best for use in titanium, inconel, fiberglass, carbon fiber.

Carbon steel, or alloy steel, or bits that don't say what they are made of are only good for aluminum.

[Milwaukee Midget]

DeWalt pilot points with no slip shanks, gold ferrous oxide.  Get 'em at Home Despot. 

I've owned a set for 6 years and have drilled everything from cast iron to polystyrene with 'em.  The pilot point keeps 'em from dancing if you're free styling with a hand drill, and they'll hold up under a press on cast if you take it easy.

There are probably better bits out there, but for $30.00 a set, I can't think of a tool I've bought lately that I'm happier with.

[Dean Los Angeles]

I always get a chuckle when drill bits come up in conversation.

I can't tell you how many times I see somebody trying to use all their arm strength to wear a hole through something with a dull drill. Why is it dull? Because they don't use coolant. They cut way too fast. They . . . Oh heck I could go on all night.

Drilling a hole takes a sharp drill. Learn how to sharpen a drill PROPERLY and you will be buying far fewer drills.

You have to learn from someone that knows how that can show you. You can also look at YouTube videos and search the web for instructions. But take the time to learn.

If the drill gets hot the strength of the material goes to hell and the drill gets dull. Coolant/lubricant and lots of it is the answer. You can't use too much.

Some things can't be drilled. At least not by you. Ever try drilling a case hardened shaft? If the item you are drilling is harder than your drill, it ain't gonna happen. And not too many have diamond drills.

Take your time. Every material has an optimum chip load.

Chip load = Feed rate / (RPM * # of Cutting Edges)
Feed rate = RPM * Cutting Edges * Chip load
RPM = Feed rate / (# of cutting edges * Chip load)

A good place to start for chip load and speeds/feeds. This is for milling, but the principle is the same.
http://www.niagaracutter.com/techinfo/millhandbook/speedfeed/index.html

[1212FBGS]

Mc Master Carr.... they have everything in stock and you can get it the next day
kent

[RICK]

There is only two things that will DULL a drill bit.  Letting it over heat/lack of lube,,,,,,,or loaning it to your buddy.



        Good luck,  RICK

[manta22]

Rick;

"There is only two things that will DULL a drill bit.  Letting it over heat/lack of lube,,,,,,,or loaning it to your buddy."

... or dropping it on the floor, point first. 

Regards, Neil  Tucson, AZ