Making the Baseplate

Each "pin" is really a sleeve or bushing over a bolt. The boll threads into a hole in the plate. I located the pins outside the perimeter of the router base, which provides a wide stance that's stable but doesn't lei you rout too close to the ends of the workpiece. If you want to, you can reposition the holes closer to the bit (or drill and tap several pairs of holes).

Accuracy is critical. The pin holes must be exactly equidistant from the bit axis, and they must be perpendicular to the plate surface.

1. Collect the hardware for the pins. You can get by with dowels as pins. But I used a router bit's pilot as a paradigm; a bearing—not a solid pin—Ls pretty much the

Outline of router base

Mounting-screw holes

Drill 'HV'-dia. hole, and cut threads for pin bolt with a ^"-20 tap.

PIN ASSEMBLY DETAIL

Cutting List

Part Qty. Dimensions

Material

Baseplate 1 VC x 8" x 8"

Acrylic

Hardware

2 roundhead stove bolts. J4H-20 x 2"

2 hex nuts, VC-20

2 plastic sleeves, VC I.D. x O.D. x 1

" long

standard these days. So I made pins with "sleeve bearings," using oddments from the local hardware store.

Buy a couple of roundhead stove bolts with a nut for each.The sleeves can lie bronze bushings or simple plastic spacers. Here are three options:

1.Use a '/«-inch-ID. x '/¿-inch-O.D. x 1 -inch-long plastic sleeve as the bearing. Cost: about 20 cents each.

2.Use a '/i-inch-I.D. X '/¿-inch-O.D. x 1-inch-long bronze-bushing. Cost: about $ 1.20 each.

3 Usc a '4-inch-I.D. x ft-inch-O.D. x 1-inch-long bronze bushing inside a Vinch-I.D. x ' »-inch-O.D. X 1-inch-long bronze bushing. Cost: about $3.50 for each pair.

2. Make the baseplate. Refer to the chapter "The Generic Baseplate" on page 63 for the details of how to

CENTER FINDING BASEPLATE LAYOUT

for Bosch plunge router

Drill 'HV'-dia. hole, and cut threads for pin bolt with a ^"-20 tap.

PIN ASSEMBLY DETAIL

Hole, tapped to VC-20 thread — , p Baseplate il \

Hex riut

'/4"-20 X I VC roundhead stove bolt

Outline of router base

Scribe diameter, and lay out pin holes equidistant from the center.

Plastic sleeve

Mounting-screw holes

Lay out baseplate on 8" square then trim to 8" dia. circle.

DRILLING SEQUENCE

I. Set stop blocks against both edges of blank, with bit hole directly under the drill bit.

Stop block r- Drill press fence Stop block

Lay out holes on acrylic blank's masking paper.

Lay out holes on acrylic blank's masking paper.

Baseplate blank Pin-hole location

Bit-hole location

Baseplate blank Pin-hole location

2. After drilling trammel-pivot hole at bit-hole location, move the right-hand stop block. Insert a 3'/2"-wide spacer against the blank, and reset the stop block against it.

Spacer

Bit-hole location

3. Shift blank against the right stop block, and drill the first pin hole.

4. Return the blank to its starting position, and reset the right stop. Move the left stop and use the spacer to reset it. Shift the blank to the left, against the stop, and drill the second pin hole.

mount the baseplate on your router and mark the bit opening. This is one of those baseplates that has to center itself on the bit axis every time it's installed, so use care in laying it out and drilling the mounting-screw holes. At the same time, try to orient the router so the plane of the handles will he parallel to an edge of the square baseplate blank.

After you've marked the center of the bit opening, but before you've bored it, scribe a diameter, as shown in the layout drawing.This diameter must be parallel to an edge. Measure and mark the pin locations. Make sure the pins are equidistant from the bit.

Drill and tap the holes for the pins. The drawing Drilling Sequence shows a good way to drill the holes and ensure that they are properly positioned. To cut threads in the pin holes. 1 used a '/i-inch-20 tap. The pilot hole for this tap can be ' /*>« inch in diameter. Be extremely careful to keep the tap perpendicular as you begin to cut the threads.This is where you get the hole out of alignment. The result is a cocked pin, which botches the accuracy of the fixture.

At the center of the baseplate, drill a '/fc-inch-diameter hole for a trammel pivot. Using a router and trammel, trim the baseplate to an 8-inch-diameter circle. Then redrill the bit hole for the largest bit you are likely to use with the baseplate.

3. Install the pins. Slip the sleeve over the bolt.

Thread a nut onto the bolt; but don't jam it against the sleeve, which would prevent the sleeve from rotating. Thread the bolt into the hole. Turn the bolt until it almost scats, then lighten the nut against the baseplate. The bolt should be light, but the sleeve must rotate freely.

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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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