Learn me about drill bits

[Nolan]

If you don't learn a little something about feeds, speeds, and material characteristics, then that $120 set of bits will not be any better than a $20 set of bits.

I fully agree. Most people do NOT know enough about drilling, especially in metal. From what I've observed, when using a drillpress, most people underfeed when drilling metals. Most people also use speeds set way too fast too, especially with medium to large diameter holes.

It's easy to do an informal survey/study by simply looking at the chips on the table of their drill presses. Another clue is what they use for cutting lube. It's amazing how may people use WD40 for drilling and threading.

 

[Scotto]

Another clue is what they use for cutting lube. It's amazing how may people use WD40 for drilling and threading.

What should you be using for cutting metal?

The only thing I could find at my hardware store was this:
http://www.acehardware.com/product/index.jsp?productId=1348155

Is this OK for drilling, or is this more for tap and dies? I've killed a few bits on metal because I didn't lubricate them - don't know what to use though.

 

[scooby074]

What should you be using for cutting metal?

The only thing I could find at my hardware store was this:
http://www.acehardware.com/product/index.jsp?productId=1348155

Is this OK for drilling, or is this more for tap and dies? I've killed a few bits on metal because I didn't lubricate them - don't know what to use though.

I use this http://www.lpslabs.com/product_pg/cuttingfluids_pg/1Gold.html

Or this for Stainless (its nasty stuff so onlu use when necessary) http://www.lpslabs.com/product_pg/cuttingfluids_pg/TriCut.html

Or RapidTap http://www.relton.com/ but LPS gold is much better and is way easier to clean up.

 

[Nolan]

What should you be using for cutting metal?

The only thing I could find at my hardware store was this:
http://www.acehardware.com/product/index.jsp?productId=1348155

Is this OK for drilling, or is this more for tap and dies? I've killed a few bits on metal because I didn't lubricate them - don't know what to use though.

That'll work fine. I've got a gallon jug of exactly that setting a few feet from my drill press as I type. I use it to fill a hand pump squirter that I keep stuck to a big magnet on the column of my drill press with the chuck keys. The Ace stuff is easy to find and the price isn't too bad.

DO NOT use it for aluminum or cast iron.

 

[Scotto]

DO NOT use it for aluminum or cast iron.

What would you recommend for aluminum (if anything because it's so soft)? Because I have some 1/4" I need to drill a few holes through.

 

[Nolan]

What would you recommend for aluminum (if anything because it's so soft)? Because I have some 1/4" I need to drill a few holes through.

I use Tap Magic Aluminum. I don't know why, but over the last few years, it's gotten harder to find anyone that stocks it.

For cast iron, I don't use any lubrication at all for drilling or tapping.

 

[Zrexxer]

I use Tap Magic Aluminum. I don't know why, but over the last few years, it's gotten harder to find anyone that stocks it.

For cast iron, I don't use any lubrication at all for drilling or tapping.

Barring a purpose-made lubricant, both kerosene and WD-40 (it's kerosene-based) work fairly well for twist bits in aluminum. Further, you actually shouldn't use any lubrication for cast iron - its high graphite content makes it self lubricating, it doesn't produce a curled chip like aluminum or steel but it drills like a dream dry.

 

[porschedude996TT]

I hate to ask, but a drill bit spinning on top of a wooden stud sounds like the drill is running the wrong direction or the bit is just plain worn out. I don't mean to sound remedial, but from the user end of the drill, as you would be holding the drill motor, the chuck should be turning clockwise. Or if you are staring down the cutting tip it should spin counter-clockwise. Just covering the basics...

High Speed Steel (HSS): Most any black colored drill is going to be (Black Oxide Coated) or (Blued) HSS and they are good for most anything. The silver colored ones are HSS without the black oxide/blued coating. The sharpened end is heat treated hard and the shank is softer to absorb mechanical shocking.

Titanium Oxide Coated Drill Bits: They are HSS with a coating to increase the durability or make them wear longer.

Cobalt Steel Drill Bits: They are used to drill hardened steel for stainless steel which has a higher degree of difficulty of machining. They are usually a different color, kind of a warm brown color and the very end of the shank is turned down or a smaller diameter to identify them.

Carbide Tipped Drill Bits are used for Concrete and Glass. The shank is HSS and they have carbide inserts soldered or welded to the tip.

Most any commercial drill bit will be good, but they don't last forever. Stay away from Harbor Freight Drill Bits because there is no telling how good they are and HF seems to me to be very inconsistent from day to day. Try a local tool supplier or even sears. Check the two below. They are factional only and will serve most home owners.

Black Oxide Fractional Set: $69.99
http://www.craftsman.com/shc/s/p_10155_12602_00964083000P?vName=Tools+&+Equipment&keyword=drill+bit

Titanium Oxide Fractional Set: $99.99
http://www.craftsman.com/shc/s/p_10155_12602_00964073000P?vName=Tools+&+Equipment&keyword=drill+bit

Bigger sets are available at many locations on the web. If I were you I would stay close to the industry type suppliers like MSC.com or Mcmaster.com

http://www1.mscdirect.com/CGI/GSDRVSM?PMTYPE=&SITEXT=DRILL SETS

http://www.mcmaster.com/

You will most likely use what is called "Jobber Length" and 135 degree angle tip which is good for most home owner stuff. Other options for harder materials are 118 degree.

For $250 you can get a full set of 1/16" to 1/2" x 64ths, A to Z, 1 to 60.

Price is the real key here...

 

[Bo Heck]

Enco is a good place to buy as well.

 

[greenreese]

That'll work fine. I've got a gallon jug of exactly that setting a few feet from my drill press as I type. I use it to fill a hand pump squirter that I keep stuck to a big magnet on the column of my drill press with the chuck keys. The Ace stuff is easy to find and the price isn't too bad.

DO NOT use it for aluminum or cast iron.

Why shouldn't you use it on aluminum?