Are there any hi speed drill bits that actually drill through metal?

[marc]

I'm trying to mount some security cameras on the sides of my home. I have old steel siding on the house. The damn drill bits I buy today can't get through the thin steel except once of twice without dulling to the point of being useless even for drilling wood. I remember decades ago I used to drill through angle iron and flat iron with no problem. Are there any non-chinese drill bits that actually drill through metal more than once or twice? The latest crap I bought were made by Irwin.

[Jon Danniken]

I have no problem drilling through steel with even the cheap harbor freight twist bits. I do, of course, use a drill press, with cutting fluid, at the correct speed and pressure though.

If you are using a hand drill you are most likely not getting enough pressure, not using a cutting fluid, and spinning the drill bits too fast, resulting in a local hardening of the metal you are trying to drill into (assuming steel), and dulling your drill bits.

You might have better luck with a step bit, but again, use cutting fluid, put some pressure behind it, and spin it at the appropriate RPM.

Jon

[nestork]

Marc:

You should not be having any trouble drilling through thin steel siding, even with a high speed steel bit.

Right now, there are three different kinds of drill bits available on the market:

1. High speed steel bits: These are the least expensive bits, but they still should be able to drill through the mild steel used to make siding.

1. Cobalt bits: These are made from a much harder steel so they stay sharp longer and can be sharpened just like any other drill bit to provide what is essentially a new drill bit. Cobalt bits have a dark brown coating applied to them so that you can tell them apart from high speed steel drill bits.

2. Titanium Nitride bits: These are regular high speed steel drill bits that have an extremely hard titanium nitride coating applied to them, giving them a "gold" colour. The extremely hard coating stands up better to wear, so titanium nitride drill bits are much slower to dull than either of the preceding two kinds of drill bits. However, sharpening of a titanium nitride drill bit grinds off that extremely hard coating at the tip of the bit, leaving you with what is essentially a high speed steel drill bit; albeit a sharp high speed steel drill bit.

You shouldn't have any problem drilling through sheet metal with any of the above drill bits, but the cobalt and titanium nitride bits will give you better performance than the high speed steel drill bits.

[Don Phillipson]

Assuming you are up a ladder with a battery drill in hand, try this: first, dent the hole site with a hammer and nail, then put a blob of axle grease into the dent, drill as slowly as you can. Report results here.

[Stormin Mormon]

I've talked to contractors who swear by self drilling screws. I've used them with varying success. That, and magnetic nut setter tips for the drill.

[Danny D.]

That!

Learned that from here, ahr to the rescue!

My old black bits wouldn't drill through steel, but, the gold-colored ones went right through.

[Stormin Mormon]

It's possible the black bits weren't properly sharp. I got some drill bits from mail order source, one time. They were simply not sharpened.

A few minutes on the drill press, and they cut fairly well.

[Danny D.]

I used to work in a machine shop when I was a teenager.

I learned how to sharpen the drill bits on a grinder from German-speaking professionals.

I don't remember the angles anymore, but, I can still hold a bit with two hands, "just right", and then ease it gently back and forth, up and down, with that slight twist at the end, to sharpen them.

It's amazing though how much better the coated ones handle steel.

[recyclebinned]

Let?s not confuse solid cobalt bits which have a shiny silver color with cobalt coated bits which may have a dark brown color.

[Danny D.]

I suspect they use them to save time.

It's my humble opinion that we, as homeowners, can do a better job, because saving time and a few dollars isn't our goal.

Our goal is to do a good job, so, it's my opinion, we wouldn't necessarily follow the contractor since they have different objectives (the bad ones anyway).

For example, on garage door torsion springs, they put in the el cheapos, saving *them* a few bucks, but not saving you anything (since it only costs a few bucks more for a really good long-lasting spring).

Still, contractors know what the good stuff is when it comes to glues and holders, since they know what they have to repeat (which I'm sure they hate) under warranty.

So, for *that*, I'd follow the contractors.

[Ralph Mowery]

I never could hold the drills correctly. Had the wife to get me a Drill Doctor for Christmas and it seems to sharpen them ok for me.

[BenignBodger]

I sent a young technician who worked for me to drill some mounting holes in some steel racks. Nothing very heavy, i gave him a couple of new drill bits along with the layout for where the holes needed to be. He came back in an hour cursing the crappy drill bits I had stuck him with and he said that he destroyed both bits drilling the first of about a dozen holes he was supposed to make. The bits were good quality and I'd never had any trouble with them but I grabbed a few more and went out with him to the equipment shack so that he could show me what was going on. I checked that he had marked and center-punched the holes properly and then set about drilling the next one myself. The drilling went much faster when I demonstrated to him that things worked fine when the drill was spinning in the _forward_ direction and not trying to burn through the steel by friction alone.

[nestork]

So far as I know, ALL "cobalt" bits are made of cobalt steel, and are solid cobalt steel all the way through. They are given a dark brown coating only so that they can be readily differentiated from regular high speed steel drill bits.

I have never heard of a "cobalt coated" drill bit.

[Stormin Mormon]

Correction: a few minutes on the GRINDER. Today hasn't been my day.

[gregz]

I have good luck with harbor freight bits. Up on the ladder I would buy cobalt. I have seen some titanium bits, dipped in gold paint ? Never bought a decent one, seem harder to find.

Greg

[Ed Pawlowski]

Really?

plus a few hundred more places.

[Jon Danniken]

Those are regular HSS bits, with a TiO2 coating (which is a dull gold in color). The coating reduces friction, which reduces heat, leading to longer life and faster drilling. You pay more for the coating than regular HSS bits, though, especially if they are good quality to begin with.

Jon

[micky]

Ptooey. Next you're going to be telling me that pliers have to be used by squeezing and not by opening one's hand.