Pilot Bit Sets

One inexpensive version is called a "screw-digger" in some catalogs. These bits


have a standard twist bit that fits into a collar. The bit cuts the pilot hole while the collar cuts the shank hole as well as the countersink and counterbore.

The length of the pilot hole can be adjusted for different length screws by loosening a small set screw. But the shank hole remains constant (very short).

Since the bit is a standard twist bit, it cuts smoothly and it can be easily replaced. For the price (under $10 for a set of four), screwdiggers aren't too bad. But there are problems: the bits often slip up the collar if the set screw isn't extremely tight. Also, sawdust tends to clog up in the flutes of the bit and in the collar itself.

adjustable scru-drill When I first saw a Stanley Adjustable Screw-Mate, I thought I had finally found the perfect pilot bit. (This bit is actually a "Scru-Drill" made by Disstim for Stanley and Black & Decker.)


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The nice thing about thus bit is that the pilot bit is adjustable in length and the shank section Is also adjustable to almost an inch long. A great idea — however, when I used the bit, I was disappointed.

The first problem is getting all these sections lined up and tightened down (especially if they're all jammed with sawdust). When you start to drill, the pilot appears to wobble since it's a half - round. It's difficult to see exactly where you're drilling.

Perhaps the most frustrating part is that the pilot bit section is so thin that it bends or breaks easily. And you can't buy this section of the bit separately.

But overall, it's the one bit that comes the closest to solving all the problems of drilling a pilot, shank and coutersink/bore all at once, with one bit.

taper bits. The bits that have received the most attention lately are the Fuller tapered drills with separate countersink and stop collars.

The advantage is supposed to be that the bits are tapered "like a screw." However, woodscrews don't really taper until the last couple threads.

Since the Fuller bits taper over the entire length of the flutes, they also cut along their entire length and consequently tend to overheat very quickly. (It's best to use them at very low speeds).

Although the taper is a nice (albeit expensive) idea, the bit by its nature is not the correct size for a pilot hole or shank hole over the depth of the hole.


Okay, the bits described above have good and bad points. But which is the best? What I've found Is that when you try to do everything at once, you run into problems. Instead, I use a two-step appproach.

First, drill the shank hole. The key here is to use a bit that drills the hole to the correct size and goes completely through the first board.

One of the best bits I've found for this is a brad point bit. (See Sources, page 24.) The brad point bit drills a clean shank hole. But it's also ideal because it can be used to mark the exact location of the pilot hole.

After drilling the shank hole, hold the second (anchor) board in place and slip the brad point bit into the shank hole. Then with a light tap or twist, the brad point will mark the centerpoint for the pilot hole.

By adding a countersink/counterbore collar, you can drill a countersink/bore at the same time as the shank hole.

After the shank hole is drilled, I switch to a standard twist bit to drill the pilot hole in the second (anchor) board. Although it's a separate operation, it usually yields a pilot hole that's more precisely located — exactly what's needed for a good joint.

Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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