Making the Fixture

The critical element is that column. If you've got a lathe and the appropriate know-how, you can make the crank column by boring a 1-inch-diameter dowel on that machine. But I'm not a turner, so 1 had to find an alternative approach. You might think, as I did 'til I tried it. that the drill press is the right tool for boring the column. But instead, use the approach I settled on after a couple of false starts. It's a bit of that router magic, I think.

Basically, you rout grooves in two pieces of wood, then glue them together. The grooves combine to form a channel for the height-stop rod and a recess for the nut. To make the

Coupling nut

To use the fixture, you remove the stop nuts or jam nuts from your router's height-stop rod, just as you do when you need to pull the motor off the plunge rods. Drop a Hat washer over the rod. and turn the fixture's nut onto the threaded rod. Start cranking, turning die fixture down onto

On a table-mounted router, the crank expedites bit-extension adjustments. No more wrist wrenching. It's now as easy as adjusting your table saw's blade. Just turn that crank and watch the bit move.

ROUTER CRANK EXPLODED VIEW

Knob

Stove bolt

Column

Crank plate

ROUTER CRANK LAYOUTS

FRONT VIEW

FRONT VIEW

Crank Hat Makeing Machine

SECTION VIEW

Channel for height-stop rod

Epoxy nut in recess.

Coupling nut

END VIEW

CRANK PLATE LAYOUT

r-dia. X H"-deep hole for column

Wrad.

3V-dia. mounting hole for crank handle countersunk for stovebolt head

Wrad.

3V-dia. mounting hole for crank handle countersunk for stovebolt head

Router Fixtures

Measure your router for the crank. Plunge it as far as it will go, and measure the rod from the yoke to its end, as shown. Also measure from the yoke to the top of the machine.

column fit the router, you rip it down and chamfer or round-over the edges.

1. Start by measuring your router. The column must be long enough to clear the top of the motor and the power cord, if it projects out of the top of the motor. (If the crank hits the power cord on every rotation, it will be as nettlesome to use as a wrist-busting knob.) The column must to bored to accommodate the threaded rod, and the diameter of the hole must match the diameter of the rod. (As I explained earlier, if this hole is too much larger than the rod, the whole crank will wobble when you turn it.)

Plunge the router until the motor bottoms on the base, and lock it. Then measure from the yoke through which the threaded rod passes to the highest projection on the router. This is the minimum length of the column. Also measure from the yoke to the top of the rod. This is the minimum depth of the clearance hole that must be bored in the column. Finally, use dial calipers to measure the diameter of the threaded rod.

2. Buy a coupling nut. This is an extra-long nut that's usually used to connect two rods that have the same thread. I elected to use this longer nut to help eliminate wobble.

Your local hardware store will undoubtedly have coupling nuts in the the National Coarse thread sizes. But most plunge routers—Porter-Cable is the one exception I can think of—have metric height adjustment rods, so you need

JT fD

COLUMN ROUTING SEQUENCE

FIRST CUT

Bit diameter = rod diameter

COLUMN ROUTING SEQUENCE

FIRST CUT

SECOND CUT

Cut length - length of nut

Bit diameter = flat-to-flat dimension of nut

SECOND CUT

Cut length - length of nut

Bit diameter = flat-to-flat dimension of nut

IHIKU LU

Cut length = length of nut V-grooving bit

COUPLING NUT HEIGHT-STOP ROD

Router Fixtures

Outside diameter of nut

Flat-to-flat dimension of nut

Diameter of rod

Here's a good fit of the rod and nut in the column pi/. The rod fits closely in its groove, as does the cou pling nut. When both column plies are glued up. the nut will be trapped and unable to rotate in its cavity, even without being epoxied.

a mctric coupling nut. Can't find one locally? Try Rcid Tool Supply Co. again. While I haven't looked at every plunge muter. I can tell you that the Hitachi M 12V takes an M6 thread, the Ryobi RF.600 an M10 thread, and the big DcWalt plunger an Ml2 thread.

The point here is simply that you must have the nut in hand before you make the column.

3. Cut the column plies. Stan with two pieces -V« X V/i X 12 inches. Good, tight-grained hardwood like cherry or maple. After the column is grooved, glued up, and ripped and routed to its final "diameter," you can crosscut it to the proper length for your muter.

4. Rout the grooves for the rod. Do this on the router table. Use a straight or core-box bit that is the same diameter as the rod. or as close to the diameter as you can come Set the depth of cut to half the rod's diameter. It's best to creep up on the perfect depth of cut. Groove both pieces, then hold them together and see if the rod fits into the channel. If the channel is too small, make a second pass on each piece, and check the fit again. If the channel is too big, start over.

In making these cuts, set the router table fence so the grooves are as close to the center of the stock as possible. And once set. leave the fence in the same place for all sulv sequent cuts.

These initial grooves can be routed through, or they can be stopped.

5. Rout the grooves for the nut. This involves rerouting the first 1 to 1 l/i inches of the groove to widen and deepen it to accommodate the coupling nut. Remember, don't change the fence position from the previous cut: merely change bits. Measure the nut from flat to flat, and use a straight bit whose diameter matches. The depth of cut should be half the bit diameter. Rout both pieces

To finish off the grooves for the nut, use a small-diameter V-grooving bit. Rout a V-groove. as shown in the drawing Column Ranting Sequence.

Check how the nut fits. You may need to cut the V-groove a bit deeper, or even switch back to the straight bit to cut a little deeper. The goal is to get the nut tightly fitted to the column.

6. Glue up the column. Line up the grooves as you clamp the two column halves. And don't overspread the glue. You don't want squeeze-out to block the channels.

73 O

Magic Block Router

The difference is obvious. The Hitachi router's stock 6-millimeter rod is clearly smaller than a inch rod. The latter rod makes it easier to adjust bit extension in predictable increments.

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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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