Drill bit ??

[Mike Jones NM]

Not really wood working but close I guess as it relates to a stick built house.
I'm installing new storm doors. One of them goes in to a metal door frame.
Drilling 1/8" holes in the frame is killing me.
Only getting 2 holes per bit. These are the dewalt bits, a little over $4.00 for 2 of them. I would expect a little bit better from them.
I tried using cutting oil but it seems to make no difference.
So, what is out there, avaliable from the local box stores, that is better?
Thanks
Mike

[David Epperson]

I do not recall ever having that problem. What are the door frames made of? Stainless? Harbor Freight runs a package of (10) 1/8" Titanium Nitride coated bits for $0.99 on occasion, as well as a similar package of ten 1/16" for the same price. in tough materials you can use the smaller bit as a pilot for the larger. But then again the last storm door I mounted had an aluminum frame. I drilled all 16 of the holes with one bit and it seemed as sharp when I finished as when I started.

[Gary Keedwell]

Don't let the "coatings" influence you. Only buy a bit that has HSS stamped on the bit shank. Unless, of course, you get a carbide bit.:)
Gary

[David Epperson]

Don't let the "coatings" influence you. Only buy a bit that has HSS stamped on the bit shank. Unless, of course, you get a carbide bit.:)
Gary
I really do not like using small solid carbide in a hand drill. They don't get dull, but snap too easily.

[Mike Jones NM]

Just drilling through a steel door frame, granted it is about 45 years old, back when they still made real steel. Only about 1/8" thick.
Had thought about the carbide but like stated in a hand drill they tend to break alot easier. Not sure if I can fnd them locally.
Thanks
Mike

[Randal Stevenson]

I was told they were more for alloy's but I would center punch, then use cutting oil and a cobalt bit.

I have bought other bits on a needed basis, and found several times that the coatings were put on after the bit was sharpened, and it dulled the bit. We experimented with those cheap HF bits my father bought for some oddball size he'd use once. After a meeting with a drill dr. they weren't that bad. (though still not everyday)

[Gary Keedwell]

If you can find a bit that has cobalt in it, that would be great. Usually they are identified on the shank as HSS-Co. There is a mixture of around 6% in the HSS ingredients.

Gary K.

[David G Baker]

Mike,
I have the Dewalt Pilot Point drill set and have used it frequently for over 4 years and they are still going strong. I do not drill stainless or hardened metal with them but I frequently drill 3/8" or thicker mild steel using a lot of cutting oil and haven't had any problems.
If by chance your metal frame is stainless, use a lot of oil, a very slow speed and a lot of pressure. You may want to look for a center drill with an 1/8" tip. The body is 5/16" to 1/4" and the tip is 1/8".
I try to use only high speed steel bits or cobalt. I haven't used the coated bits yet but have heard that high end bits that are coated are awesome.

[Gary Keedwell]

Now that I have given it some thought...putting adequate pressure is very important, too. Often it is hard to get some leverage when you are drilling in a horizontal plane.
Gary

[Gene O. Carpenter]

Gary hit the nail squarely on the head ! If you don't put enough pressure on the bit point it won't start that scraping action that results in the 1st chip..All you'll do is create heat which will harden the steel that you're trying to drill thru. This is called "work hardening"! As was said in one of the preceding posts, center punch with a sharp pointed awl :<) or a center punch, this will break the surface and give the bit something to bite on initially. The as you apply pressure you'll see little chips coming off, add more pressure til you get little curly pigtails and hold that pressure til you feel the bit start to exit the other side then let off pressure slightly so you don't ram thru, hit the drill chuck which might cause your hand to move position and could snap the bit.
If by any chance you drilled a smaller pilot hole encountering this dulling of the bit you will have hardened that spot completely thru the steel and you'll have trouble enlarging that hole using a larger bit. The outer lip will lose it's edge and goodbye bit.
Those Taiwanese elcheapo's are ok to a point! If you don't center punch AND immediately start applying pressure you'll lose the edge and the "work hardening" will commence..
Unlike working with wood if you cut or drill a piece of steel wrong you can always hit it with a mig welder and start over again. But then with today's glues, epoxies and finger joint bits you can do the same with wood!
They also have "self tapping" sheet metal screws which have a sort of paddle point rather than a sharp point such as on wood screws, it has 2 sides each sorta shaped like the carbide on a masonry bit. These 2 edges scrape an entrance hole for the larger threaded shank to thread it's way into..The only drawback is they have a hex head which requires a hex head drive socket and can't be countersunk..But you could drill the hole, remove that screw and install the required screw.
If you want to mig up one of those holes and you have a long,long,long 220 Volt ext cord I'll run my mig welder over for you..;<)
I have also seen guy's take one of the scratch awls that has the shaft all the way thru the handle, a hammer and 2 whacks they're thru those door jams. Leaves a very slight indentation but it doesn't matter if it's going to be covered.

[Dale Lesak]

My local Ace Hardware store carries a line of bits called "ARTU" I had to drill some holes in a 1" Hardened shaft. None of my "good" bits would touch the stuff. got one of those bits and it drilled it like butter. Called the co. to see what I should use as a cutting fluid. was told light oil or water mist. my other bits would not even scratch the shaft. Just flattened the center punch. www.artu.com (http://www.artu.com) :)

[Randal Stevenson]

What does everyone use for cutting oil?

The old mechanics I knew, used transmission fluid, or normally straight 30 weight oil, as it was handy. I've seen 3 in 1 used, but normally whatever oil was around.

[Mike Jones NM]

From my days of drilling in HARD firearm receivers, "Do Drill"

[joe greiner]

Aside from whatever they put in the pot when they make it, cold-rolled steel undergoes work-hardening in the rolling process. Bed frames are just about the worst I've worked besides stainless.

Cobalt bits are the choice, like Gary says. I never noticed it before, but yes it does have "HSS" stamped on the shank. DeWalt DW1212 is 3/16", and DW1220 is 5/16". I'd guess DW12xx would be for other sizes. DW11xx are ordinary bits.

I've occasionally used the cobalt bits on bed frames dry without incident, but a spray of WD-40 seems to help.

Just my personal bias, but I think the coatings are more marketing than engineering.

Joe