Setting The Bit Height

After the bit is firmly chucked in the collet, you need to set the height. This isn't a diflicu It task by any means, but a couple of tricks can make the job easier and the result more accurate.

First of all. use a steel ruler rather than a tape measure. The hook riveted to the tape makes the first inch of the tape virtually unusable for measuring purposes. Of course, the first inch is the most important in setting the bit height.

A practical measuring device is a 6-inch steel rule, which you can usually buy at an art-and-drafting supplies store. A lot of woodworkers keep a combination square at the router table and use it to set both the bit height and the fence. These squares have a variety of graduations on the rule, one of which is certain to suit your purpose. A 6-inch square is ideal to use with the router table, in my estimation.

To set the bit's height accurately, you need to get your line of sight even with the bit. Stand the rule right next to it. It helps immeasurably to have the bit opening in the mounting plate closely matched to the bit diameter. A '/»-inch dovetail bit jutting through a 2-inch opening isn't one your rule can cozy up to. (This isn't a particularly safe operating situation, either.) Using the combination square is your best bet here.

You can make an alternative

A good steel rule is ideal for setting bit height. Ihis one has the first inch graduated in 32nds. Machinist's rules often are graduated to 64ths, which is too fine for my bifocaled eyes. For my router work, 32nds is usually sufficient.

Where the bit opening is not closely matched to the bit diameter, a combination square is the best for setting bit height. You can stand it next to the hit, then use both hands to adjust the router.

Fit an O-ring—buy 'em al an auto-parts store—on the shank of each bit you have. The rubber ring will catch on the collet and limit the shank's penetration into it. In most cases,you'll position the ring to keep the bit from bottoming. On short-shanked bits, this will be near the cutter.

Need three hands to change bits? When you do this with the router in "table position," it often seems that way, especially if you want to avoid bottoming the bit (that is, letting the bit rest against the collet bottom). And dl bit makers entreat you to avoid bottoming the bit. (See the chapter "Bits" for the reasons why.)

Here's a trick to try.

To me, the most accurate, controllable bit height adjustment is offered by plunge routers equipped with a so-called micro-adjusting knob. This is a sort of "manual override" of the machine's plunging action. As you rotate the knob, the router is forced steadily down the plunge rods (or allowed to steadily slide up the rods). Because the knob is turning a nut on a threaded rod to cause the movement, you should be able to convert the rod's threads-per-inch into a ratio of bit height movement. For example, if the rod has 20 threads per inch, turning the knob five times should raise or lower the bit 'A inch.

Some plunge routers have a micro-adjusting knob as standard equipment, but you can buy one for those that don't. Check with Wood-haven and Eagle America (see "Sources" on page 337).

Not only is the vertical movement thus controllable, the plunge router's structure prevents the bit

Fit an O-ring—buy 'em al an auto-parts store—on the shank of each bit you have. The rubber ring will catch on the collet and limit the shank's penetration into it. In most cases,you'll position the ring to keep the bit from bottoming. On short-shanked bits, this will be near the cutter.

approach possible by making a simple adjustable depth gauge. Join two scraps of wood with a sliding dovetail joint, and apply a short length of adhesive-backed measuring tape to one of them. Instead of trying to carry a graduation by eye from your role to the bit. you can rest one segment of this gauge atop the bit and easily read the graduation next to it. See Adjustable Depth Gauge for dimensions and construction details.

There's one critical element of bit height adjustment we haven't mentioned yet. That's the router's adjustment mechanism.

A good steel rule is ideal for setting bit height. Ihis one has the first inch graduated in 32nds. Machinist's rules often are graduated to 64ths, which is too fine for my bifocaled eyes. For my router work, 32nds is usually sufficient.

Where the bit opening is not closely matched to the bit diameter, a combination square is the best for setting bit height. You can stand it next to the hit, then use both hands to adjust the router.

Using this shop-made depth gauge eliminates bending and squinting. Set the height you want, then set the gauge over the hit. Crank the hit up until it touches the end of the slide. With a piloted bit, you simply have to Ih' sure that the slide is jtositioned clear of the pilot and that it is touched only by the cutting edge.

CONTROLLING THE WORKPIECE

Sideplay in the depth-of-cut mechanisms of some fixed-base routers can lead to less-than-perfect finished aits. Eliminate this problem by using a spacer to lift the work piece for the first pass. The spacer should extend the full width of the tabletop, but it need be only wide enough to cover the area bi'tween the fence and the table's front edge.

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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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