Shank Size

The majority of router bits made today have either '/finch or '/2-inch shanks. Which size should you buy?

Look at the photo comparing the two shank sizes. Though the bits cut the same profile, they look dramatically different, simply because one has a '/2-inch shank and the other a '/»-inch shank. The choice is obvious, isn't it? The Winch shank is bigger and thus stronger and thus better resists bending or breaking. While vibration in a long bit or large-diameter bit is usually amplified, the extra heft of the Winch shank will eliminate most vibration for a steady, smooth cut. If you shop around— drag out those catalogs!—you'll find that Winch-shank bits cost the same or only a little more than those with thinner shanks. You'll find, too. that the larger profiles and all the big joiner)' and specialty bits are available only in the Winch-shank configuration. (You may also discover that a few manufacturers have Winch-shank bits. But the variety is limited, and there doesn't seem to be any sound reason to invest in them.)

Nevertheless, there may be two good reasons for buying Winch-shank bits. One, your only router won't accept a '/2-inch collet. Two, the bit is available only in the '/»-inch shank.

The questions for woodworkers who own Winch-collet routers are: Do I continue to buy Winch-shank bits? Or do 1 first upgrade to a Winch-collet router? Only your work can provide the answer.

But consider this: As you ask more of your router, you undoubtedly will seek out larger bits. A 2-inch-diameter cutter on a W inch shank is pushing it. And a

1-horsepower router (probably the maximum produced by a Winch-collet-only machine) driving a

2-inch-diameter bit is stressed to the max. Purchasing a higher-horsepower router—it'll come with both Winch and Winch collets— will let you use all your Winch bits, but it'll also broaden your woodworking opportunities by letting you use Winch-shank bits, too.

BIT DRAWER

BIT DRAWER

Here's Bill and Fred's Excellent Bit Set. If you're buying your first router, and you don't have a specific genre of woodworking in mind, these are the bits Fred and 1 suggest you buy to get started: Winch and Winch straights; Winch, Winch, and Winch round-overs; and a Winch rabbet with extra bearings. The fledgling sign-maker should buy a V-groover and Winch and Winch core-box bits. For even the most basic laminate work, you need a Winch or Winch flush-trimmer and a bevel-trimmer.

What you usually discover, as I did with my first set, is that these "starter" sets invariably include a couple of bits you seldom—if ever— use. That can put you off.

Naturally, the tendency is to dwell on that "if ever." Money spent on a bit never used is money wasted, of course.

But dwell instead on that "seldom." There arc lots of bits in those catalogs that are seldom used. And in the collections of longtime router woodworkers, there arc lots of "seldom-used" bits. But when one of those bits is needed, even if only for a single job. and no other bit can be substituted, then that bit becomes essential. Seldom used, but nonetheless essential. What I'm saying is: Don't let someone's gibe about "seldom-used bits" spook you. If the set's a good buy, a really good price, go for it!

An angle sometimes overlooked is that you don't realize how useful a particular bit is until you have it. In its absence, you work around certain joints or procedures. Then one day you spring for it. Suddenly you're discovering timesaving routines, you're trying more sophisticated joiner)', joiner)' you had avoided as too difficult. And it's all easy!

Don't overlook specialty sets. Freud and Amana have sets of straight bits. The straight is the most basic bit, and if you are starting out. what better way is there to get a range of sizes? Others have sets of edge-forming bits: two or three round-overs, a Roman ogee, coves, a rabbet, and so forth. Eagle America packages five sizes of the same profile as a set—five coves or five round-overs, for example.

After you've got the basics, whether you bought a set or built up a basic collection bit by bit. expand your collection job by job.

USING BITS

There is a little more to using a router bit than slipping it into the router collet and cinching the collet nut down. You've goi to match the

Using a bit with a cutting edge that's overly long for the job can lead to a broken bit. A 2-inch-long straight may be just right for tenoning, but it's way too long for a Yt-inch-deep groove. Most of us have a limited selection and use a midlength cutter—Yt to I inch long—for both jobs.

bit to the cut and the router. You've got to balance the bit speed with the feed rate. Here are some tips for using your bits to their best advantage.

Bit selection. Always use the bit with the shortest cutting edge that will do the job. The longer the bit. the greater the chance of its breaking. This is because excessive length amplifies vibration and deflection, which manufacturers cite as the leading causes of tool breakage. If you arc cutting a Mi-inch-deep dado, use your dado bit with the '/«-inch-long cutting edges, rather than your straight bit with the 114-inch-long cutting edges.

Always use the bit with the largest-diameter shank you can. (See "Shank Size" on page 25 for the rationale.)

Pilots. Each time you fit a bearing-piloted bit in your router, give the bearing a flick to ensure that it spins freely and that its rim is smooth and clean. A frozen bearing is the prime cause of tracks and scorch marks on the edge of a workpiece. but perhaps surprisingly, it isn't the only cause.

The purpose of the pilot is to guide the cut and to control its width. In the days when HSS was what all bits were made from, pilots were turned steel pins. You needed a light touch to avoid bum marks left by a pilot spinning at the same speed as the cutter. Nowadays, you need a heavier hand to avoid those bum marks. The bearing is supposed to roll along the workpiccc edge at the feed rate, while the bit spins inside it at the router's speed. But if you don't put enough pressure on that bearing, it can spin along with the bit and really stink up the edge, if you knew what I mean. (On the other hand, press that bearing too

The bearing really does have impact on the cut, and a dirty one like this—okay, okay, we exaggerate— causes an uneven finish. Instead of rolling evenly along the workpiece edge, it thumps along like a grocery cart with a gob of gum on one wheel. Even a tiny scablikc pitch deposit can impact the cut enough to detract from its final feel and appearance. But even a clean bearing can damage the work, as the top workpiece shows, if it is frozen or pressed too hard against the wmtd during the cut.

The bearing really does have impact on the cut, and a dirty one like this—okay, okay, we exaggerate— causes an uneven finish. Instead of rolling evenly along the workpiece edge, it thumps along like a grocery cart with a gob of gum on one wheel. Even a tiny scablikc pitch deposit can impact the cut enough to detract from its final feel and appearance. But even a clean bearing can damage the work, as the top workpiece shows, if it is frozen or pressed too hard against the wmtd during the cut.

hard against a softwood, and you crush the wood fibers, leaving a different son of track along the edge.)

Dirt or grit stuck on the bearing's rim can cause a wavy or choppy cut. The dirty pilot acts like a kind of cam, lifting the cutting edge infini-tcsimally away from the work each time the dirt speck hits the guiding edge. (The same unsatisfactory finish can be achieved by running a clean pilot along a dirty, chipped work edge, by the way.)

That integral pilot on the HSS bit has one big advantage over the typical pilot bearing—its small diameter. That allows you to cut deeper into a comer than a '/:-inch or Mi-inch ball-bearing pilot.

On the whole, though, the integral pilot is inflexible. Its size is what it is. But a bearing can be changed, thus altering the width of the cut ttTTtflC, AiFIR^GRIP

FITT1N4 A BIT IN A COLLET

SOME PROBLEMS..

SOME PROBLEMS..

BIT BOTTOM IS SUCUTIY iKEWEO. COLLET ORAWS IT TIC.UTER TO BOTTOM, PREVENTING IT FROM RliUTlNC,. Orr-CENTER BY I OR 2 TUOUSANOTUS. TUE BIT VIBRATES.

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FITT1N4 A BIT IN A COLLET

COLLET

COLLET NUT SHANK

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ARMATURE SUAFT

COLLET SEATS AGNNST LOW.NOT BROAD S4ANK. WITH BIT ONLY PARTWAY INTO THE COLLET, TUt MUT IS A&IE TO SQUEEZE TUE BOTTOM MORE DEFORMING COLLET BORE INTO CONKAL SHAPE.

BIT BOTTOM IS SUCUTIY iKEWEO. COLLET ORAWS IT TIC.UTER TO BOTTOM, PREVENTING IT FROM RliUTlNC,. Orr-CENTER BY I OR 2 TUOUSANOTUS. TUE BIT VIBRATES.

COLLET SEATS AGNNST LOW.NOT BROAD S4ANK. WITH BIT ONLY PARTWAY INTO THE COLLET, TUt MUT IS A&IE TO SQUEEZE TUE BOTTOM MORE DEFORMING COLLET BORE INTO CONKAL SHAPE.

ARMATURE SUAFT

COLLET CATCUES TRANSITION FILLET. OOESN'T SUT XtAINST SUANK. BIT IS THUS NOT SECURED.

WITU ONLY BOTTOM Vit* OF SWANK IN COLLET. LEVERAGE AMPLIFIES FORCES TRYING TO BREAK TUE SUANK.

COLLET CATCUES TRANSITION FILLET. OOESN'T SUT XtAINST SUANK. BIT IS THUS NOT SECURED.

WITU ONLY BOTTOM Vit* OF SWANK IN COLLET. LEVERAGE AMPLIFIES FORCES TRYING TO BREAK TUE SUANK.

A side benefit of having a bearing as a pilot is that it can be removed. A different-sized bearing can replace it. This will affect the width of cut. The bigger the bearing, the more shallow the cut. as these samples show. All were cut with the same bit and different bearings.

to yield different profiles from the same bit.

The collet. Always use the correct collet for your router, and avoid using sleeves or bushings to make a Winch-shank bit fit in a 14-inch collet.

These reducers add to vibration and runout, and they generally don't hold the bit as well as a collet alone. (A number of router manufacturers don't make separate Winch collets for their Winch-collet machines, and if you've got one of them, using a bushing is unavoidable.)

Usinga collet that's in good condition is essential. A worn, scored, or out-of-round collet doesn't hold the bit tightly, which increases runout and vibration. Don't assume that a new collet is perfectly round or even the correct diameter. Check the shank each time you remove a bit from tic collet. Dark marks or grooves in it usually indicate slippage. Either you didn't tighten the collet nut sufficiently or the collet is worn and should be replaced.

Always insert the shank as far into the collet as it will go. then back it out slightly (approximately V\t> inch). The reason for doing this is to ensure that the collet alone is securing the

.4 quick scan of our bit drawers suggests that the typical bit's shank is I to I'A inches long. If that shank is a half-incher like the core-box shown at left, its entire length needs to be in the collet. If it's a quarter-incher like the cove bit, you can extend the bit's reach a little, as shown. Most manufacturers will provide extra shank length when it seems clear it will be needed. The dovetail and ogee bits shown arc likely to be used with template guides, so the extra shank length is there.

.4 quick scan of our bit drawers suggests that the typical bit's shank is I to I'A inches long. If that shank is a half-incher like the core-box shown at left, its entire length needs to be in the collet. If it's a quarter-incher like the cove bit, you can extend the bit's reach a little, as shown. Most manufacturers will provide extra shank length when it seems clear it will be needed. The dovetail and ogee bits shown arc likely to be used with template guides, so the extra shank length is there.

bit, and that the shank is centered in the collet. If you bottom the bit. and leave it bottomed when you tighten the collet nut, the bit can be off-center by a thousandth or two. That's enough to cause pretty severe vibration.

How deep the bit shank must be inserted in the collet is not something all bit manufacturers agree on. Most urge you to avoid cheating the bit out of the collet to extend its reach. It is a tempting idea. You need to cut jjuuussst a little deeper, so you back the bit out of the collet an extra 'A inch or an extra Vi inch. The maker of Byrom bits says the minimum insertion is twice the shank diameter. As a practical matter, you don't always have a lot more length than that on '/¿-inch-shank cutters. But having a hefty cutter on a Winch shank inserted only Vi inch into the collet seems excessively venturesome to me. Bear in mind that Byrom also recommends the Winch shank for any bit over Vi inch in diameter.

Feed rate. The rate at which the router is fed along the work (or the work is fed across a router table) is very important to the overall quality of the cut and to the longevity of the bit. You should feel a constant, even pressure when the work meets the cutter. Feed rate ultimately depends on the type of material being cut, the amount of material being removed, and the type of bit being used.

The most common feed rate mistake is excessive restraint. And feeding too slowly is a quick way to ruin a bit. Letting the bit "dwell" in the cut will lead to a burned cut, caused by the bit heating up, which in tum reduces the bit's life immensely. Remember, heat can ruin a sharp tool. So keep the router (or the work) moving.

If you are concerned about bogging the router down, make several light passes to complete the cut instead of trying to hog away too much material in one pass. This is especially true if you are using a large-diameter bit. This will reduce the stress on the bit and will generally be a safer practice.

Router speed. The speed at which the bit turns can be important. The typical router runs at somewhere between 20,000 and 24,000 rpm. depending upon the brand and model. Router bits are designed to cut at

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TIP SPEEDS

Each point along the cutting edge of a 3'/i-inch-diameter bit is traveling a different distance in each rotation of the hit. The farther out from the centerpoint you go, the faster the point musí move. The critical point is the very tip. At 22,000 rpm, the tip of a Vhinch bit is moving 49 mph, while the tip of the 3 Wirtrh hit is moving 228 mph. A tip s/>eed of 130 mph is probably the maximum you should run to achieve optimum cutting performance with appropriate safety.

Dwell hunts are a common woe in router woodworking. Feeding the router loo slowly or at an erratic pace is a common cause. A dull bit will bum the wood, regardless of the feed rate. And, unfortunately, some species of wood—maple, for example—burn more easily than others.

this operating speed. If you were to run the typical router bit at a reduced speed, say 10,000 to 12.000 rpm. you might be surprised at how poor a job it does. The finish of the cut probably will be rough and choppy.

This is true of most bits. But as the diameter of the bit increases, the router's high operating speed becomes a problem. The cutter is too dam big to be revolving at 22.000 rpm. While there's little dispute that lai^c-diameter bits—for example, 3-to 3Vi-inch-diameter panel raisers— should be spun at about 12,000 to 14,000 rpm, opinions vary as to the the appropriate speeds for other sizes of bits.

One bit source recommends operating any bit larger in diameter than Vi inch at no more than 17,000 rpm, and cutting that speed to no more than 14.000 rpm when the diameter exceeds 1 inch. More commonly, you're advised to slow down the bit when its diameter hits 2 inches.

What's working here is a confusion between safe operating speed and an appropriate balance between bit speed and feed rate. We slow down big bits simply because they're unsafe at "full router speed." But we often slow down midsized bits so a workable balance can be struck between bit rpm and feed rate. As 1

mentioned before, a feed rate that's too slow is common. The bit moves too slowly through the cut. the heat builds up, the wood scorches.

The prevalence of plunging operations fuels this problem. Say you have a short slot to cut. Each time you want to plunge the bit deeper, you tend to pause, allowing the spin ning bit to dwell in the cut. You can just smell the wood scorching. The cut is short, and each change in direction brings another slowing of the feed rate, another pause. One way to moderate the problem is to slow down the bit's revs—even when the cutter is relatively small in diameter.

BIT DRAWER

BIT DRAWER

Is one bit safer to use than another? Some bit manufacturers would like you to believe so. CMT and Freud promote their bits as having "anti-kickback" designs, and Byrom. perhaps more blatantly, has marketed selected bits as "Safety Bits." By the time you read this, Eagle America will have switched its line to anti-kickback designs.

The concept comes from the European Community. A number of years ago. the Holzbetvfsgenos-senschaft. the German woodworking safety commission, came up with a bit design that limits the size of chip that a cutting edge can remove.

The difference between a "non-safety" bit and a "safety" bit is most obvious in large-diameter edge-forming cutters, such as cove, chamfer, ogee, and round-over bits. Basically, the bit body is bulkier, with a very pronounced yet confined pocket just in front of each cutting edge. The design key, however, is not that pocket but the fact that the radius of the bit body is just Vx inch smaller than the radius of the cutting edge. The design makes it almost impossible for the bit to aggressively pull the router into the work, and it puts a governor on the rate at which vou can feed the router.

Sajety bits (bottom) have more body than non-safety bits (top) of the same profile. The extra body limits the size of the chip that can be removed.

ANTI-HJCKBACK BIT DESI&H LIMITS CUIP SHE. , HOLDS DOWN FEED RATE.

X SfcftTY BtT CAM SUCE OWIV hi* FROM THE CUT PER REVOtUTlOW .

wwcm stows Tut feed rate.

"SAFETY' «ARRETING »IT

STANDARO BIT PUU.S LARGE. CUP. TUUS CUTS QUICKLY

STANDARO BIT PUU.S LARGE. CUP. TUUS CUTS QUICKLY

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The three manufacturers promoting the safety aspect of their bit designs have strong European connections. To sell in Germany, one of the world's healthiest markets, their bits have to meet the safety-design standards. Both CMT and Freud bits are manufactured in Italy and sold around the world. Ohio-based Byrom sells its American-made bits internationally. (Bosch, a German-based router and bit maker, naturally has chip-limiting hits available, but at this wiiring it isn't pushing them in the U.S. market.)

Okay. okay. So is the safety element truth or hype?

Truth, I'd say. It's subjective, of course, and it's based on work with CMT bits (the Freud bits we have predate their changeover to anti-kickback designs), but 1 find the CMT bits to be among the least "grabby" I've ever used. Though climb cuts aren't recommended, there are times when a climb cut is what you make—when routing stock that's prone to tear out, for example. With an anti-kickback bit, a climb cut seems less of a thrill. I think that's a recommendation.

Check "Sources" on page 337 for where to find CMT, Freud, Eagle America, and Byrom bits. Give the suppliers a call; get their catalogs. Their bits aren't the cheapest you can buy. but they just may be the safest.

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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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