Drill Bit Questions

[fleemo17]

In an attempt to expand my tool collection, I just purchased a

228-piece drill & screwdriver bit set. The set came with no information on the bits, so, being a novice, I have plenty of questions:

=B7 In addition to standard wood and masonry drill bits, the set included "H.S.S." drill bits with both Titanium coating and bits with black oxide coating. When would I use these over the standard bits, and when would I use one over the other? And what does "H.S.S." stand for?

=B7 The set includes three plastic "screw finders." How are these used?

=B7 The set includes both a "Quick Changer" and a "Bit Holder" which appear to do the same job, allowing you to pop bits in without dealing with the chuck. Is there a difference between the two?

=B7 And for Pete's sake, it takes an act of God to get any of the pieces in or out of their molded plastic slot in the case. Is there a trick to removing/replacing them?

Many thanks.

-Fleemo

[Robert Allison]

HSS is high strength steel and is used for drilling in steel and other metals. You can use these in wood also, but you can't use wood bits in steel. I can"t tell much difference between the titanium and the black oxide bits.

Screw finders are used to drive screws in that the sliding sleeve will hold the driver on the screw while starting it or removing it. The sleeve slides over the screw and the bit can't slip sideways off the screw (although it can still slip out of the slot). It is just for making it easier to drive screws or remove them in some instances.

A quick changer usually has a bit driver that slips over a drill bit. This is especially useful when you need to predrill holes for screws. You predrill the hole with the drill bit, then slide the driver part over the drill bit and drive in the screw. Remove the bit driver and repeat for the next screw.

Robert Allison

[fleemo17]

Robert, thanks for the quick reply!

Thanks for the explanation on the HSS bits and the screw finders. Very interesting.

I don't think this particular quick changer is the same as what you're thinking of. It isn't something that can slip over a drill bit. Like the bit holder, it's basically consists of a female slot for the bit to sit in and a male shank that goes into the drill's chuck. It functions the same as the bit holder, but I don't know why they'd include both. Thanks for your help.

-Fleemo

[Larry]

HSS stands for high speed steel. It retains its strength at high temperatures such as drilling metal and machining metal in a lath.

[CW]

The titanium nitride coated bits really excel when drilling titanium and inconel.

228-piece drill & screwdriver bit set. The set came with no information on the bits, so, being a novice, I have plenty of questions: · In addition to standard wood and masonry drill bits, the set included "H.S.S." drill bits with both Titanium coating and bits with black oxide coating. When would I use these over the standard bits, and when would I use one over the other? And what does "H.S.S." stand for? · The set includes three plastic "screw finders." How are these used? · The set includes both a "Quick Changer" and a "Bit Holder" which appear to do the same job, allowing you to pop bits in without dealing with the chuck. Is there a difference between the two? · And for Pete's sake, it takes an act of God to get any of the pieces in or out of their molded plastic slot in the case. Is there a trick to removing/replacing them?

Many thanks.

-Fleemo

[Andy Dingley]

High _Speed_ Steel.

Originally developed for lathe tools, it's a hardenable tool steel that remains hard at high temperatures. Older steels would lose their temper if overheated. It also has some minor advantages for toughness. Just about the only difference you'll notice is that it's slightly easy to sharpen, because there's less risk of overheating

All reasonable quality twist drill bits are made from HSS (plain "carbon steel" is someone trying to sell you junk).

TiN (the golden coating) is vaguely useful for steel or abrasive materials, but not hugely so. It really only makes a difference if you are drilling stainless steel with good quality drill bits.

I'd suggest a set like this, because it's cheap and it gives you good coverage of all the sizes. If you work metal as well, you'll find you do most of your drilling with a very few sizes - some of these are "odd" sizes, used as tapping drills for a threaded hole. Here it's also worth buying a few ten-packs of _good_ quality black HSS drills (Dormer, Presto brand etc.), especially in those fragile sizes under

5mm.

Other good drills to have are a set of "brad point" drills. These are for drilling wood, _not_ metal, and have spurs at the edge to cut the wood fibres. You'll get a better surface and edge to holes drilled in fibrous softwoods. They can't be re-sharpened as brad points, but they can be re-sharpened as twist drills for general use.

Drills can't be sharpened. They can, but it needs a jig which costs more than a lot of extra drills. It's really not cost effective for almost anyone.

[Steve Dunbar]

There are two different types of hex-shank screwdriver bits. One type, the "power drive" bit, has a groove in its shank that locks into a chuck. The chuck works by pulling its outer sleeve forward to relaese. This may be what your "quick changer" is. The other type of bit, the "insert bit", has no groove and is usually very short. Insert bits are used with magnetic bit holders.

There's a picture of a power drive bit at

and an insert bit at .

[fleemo17]

Thanks everyone, for your help with this. I'm still curious, though, what the black oxide drill bits are intended for.

And Steve, you solved the mystery. Thanks for clearing that up. The photos really helped too.

-Fleemo

[Roger Shoaf]

TiN coating is basicly for production environments where the down time for bit changes is a big factor. For home use it is seldom an issue.

I disagree here. I often sharpen twist drills by eye with nothing more than a fine stone on a bench grinder. The trick here is to understand the geometry of the cutting angles etc. Keep some of the ones you would otherwise toss and compare them to a sharp drill. Things to keep in mind are keeping each cutting edge even and getting the relief correct. A jewelers loupe helps.

As far as bead points go you can get more mileage out of them also, a careful stroke with a thin diamond file will restore a dulled edge.

[Roger Shoaf]

The black oxide coating is kind of like Teflon in a frying pan or chrome on your bumper. It is like Teflon in that it allows the metal being drilled to slide rather than stick allowing the built up heat to be carried away in the chip rather than stay in the bit. It also helps resist corrosion better than plain steel.

[Edwin Pawlowski]

I don't doubt that you can. You are probably 1 out of 50, or 100 or even

500 that can. The rest of us don't have the right grinder, let alone the right technique to do it. In the past year I probably spent $5 on twist drills. It would take me 20 years to justify a Drill Doctor.

[Mike Marlow]

I sharpen my own also, so I think we're up to 2 out of 50 or 100. But... I generally sharpen them in the interest of time, not in the interest of savings. If I break a bit, it's easier and faster to hit it on the grinder or the belt sander than it is to run to the store for a new one. Sometimes I have to question the "faster" part - there are those times when it seems I get every angle wrong and it takes a few passes. What has surprised me in the past is how dull some otherwise good drill bits were right out of the box. A quick hit and they cut like a hot knife through butter, but out of the box they smoked more than they cut. And I'll take your point one step further Edwin - I don't believe one *can* justify the cost of a Drill Doctor.

[Robert Allison]

Your welcome. And the other responders are correct, it is high SPEED steel. I get that confused all the time.

And another poster accurately described the quick changer as a bit holder. Here is an example:

quick changer that I was talking about is actually a drill bit holder with a sleeve that fits over it that holds a driver. You pull off the driver sleeve which exposes the drill bit. You predrill your hole, slip the driver sleeve over the drill bit and drive in your screw. I went and looked at mine, but the label has long since worn off and I can't remember the proper name for it.

(By the way, it is right in the tool box next to the quick changer which I never use.)

Good luck with your set. The other poster who advised getting a bunch of the drill bit sizes that you use often is right on.

[fleemo17]

Hey Robert,

The quick changer that you're referring to sounds like the perfect solution to the tedious switching out of drill bits and driver bits. I'd love to get my hands on one, if you or someone else can remember what it's called.

-Fleemo

[Edwin Pawlowski]

I just bought a Bosch, but others are available. It is simply a Quick Change Chuck.

[fleemo17]

Oh, thanks Edwin, I get it now! The drill bits have hex shanks just like the driver bits so they fit the quick change chuck. Unfortunately, none of the 150 drill bits that came in the kit have the hex shank. I don't suppose they make a hex adapter so standard round-shank drill bits could pop into a quick change chuck?

-Fleemo

[Edwin Pawlowski]

Some sizes.

have a couple of hex type drills with countersink, but they do not havethe groove at the end to hold securely in the chuck. They go in OK, butwill slip out of the chuck when you pull it out of the hole you justdrilled. I've only had my quick change bit about a month and I do like it for somework. When drilling a pilot hole, then driving a screw, and back again, itis very handy.

[Robert Allison]

That is not the kind that I have. The drill bit is always on the chuck. The driver sleeve fits over it to drive the screw and then back off to predrill.

I will see if I can find it on the net.

[Robert Allison]

For all those that were interested, I have found a driver like I was talking about. It is not exactly like mine, but it works the same way.

[fleemo17]

Thanks for the link Robert.

So my question is whether I can use my dozens and dozens of drill bits with a setup like that, slipping the drill bits into a hex shank adapter, or whether I have to buy special drill bits that come with the hex shank built into them?

-Fleemo