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Changing Grits Takes Only Seconds

A unique twist-and-lock design lets you change grits as easy as changing a CD.

We've taken the driver unit and an abrasive disk out of the drill press to show you how they work together. When you're actually sharpening, the driver stays in the drill press.

Slide the abrasive disk onto the driver. The driver contains a metal bar that fits into a groove on the abrasive disk.The driver also has two rare earth magnets that lock the abrasive disk in place after the two disks are twisted together.

Twist the abrasive disk. It locks Into place automatically in a second groove.To release the abrasive disk, simply turn it in the opposite direction and slide it off.

Common Hardware, Tools and Skills

All the parts of this jig are made from 3/4-in. medium-density fiberboard (MDF), primarily because it's very flat. Baltic birch or ApplePly plywood would work well, too (see Sources, page 110), but shop-grade birch plywood won't cut the mustard. MDF is fairly inexpensive (about $30/sheet)and you'll only need half a sheet or a bunch of scraps.

Most of the hardware for the jig is garden-variety stuff (see Shopping List, page 74). A few crucial items can only be found in a catalog (see Sources, page 110.) Altogether, the hardware costs about $30.

As for power tools, of course you'll need a drill press, but it doesn't have to be a floor model. A 10-in. benchtop will do, and you can buy one for less than $100. (The only requirement is that the drill press must have at least 10-1/8 in. of clearance between the bottom of the chuck and the top of its table.)

You'll need a set of twist drill bits up to 1/2-in. dia., a metal-cutting countersink, 1/2-, 5/8-, 3/4- and l-in.-dia. Forstner bits and a 3-in.-dia. sanding drum. A self-centering hinge bit is optional (see Sources, page 110). You'll also need a tablesaw and a stacking dado set. A band-saw helps with cutting the round parts, but a jigsaw is okay.

You'll also need a hacksaw with an 18-tooth-per-inch blade, an 8- or 10-in. flat bastard-cut file, an 8-32 NC tap and handle and household lubricating oil.

Getting Started: Laminate the MDF

Begin building the sharpening system by gluing together all the parts that are made from two thicknesses of MDF.

1. Rough cut pieces for the driver (A1), the fixed support (CI), the moveable support (C2), the crank (C4) and the lapping plates (El) (see Cutting List, page 74).

2. Clamp and glue the pieces together

(Photo 1, page 68). It's okay if the pieces don't perfectly align while you're gluing, because they're meant to be at least 1/2-in. oversize in width and length.

Make the Lapping Plates

Now make a set of flat blocks, or lapping plates, for flattening and polishing the back side of your chisels and plane irons. Lapping a tool requires removing a fair amount of very hard steel. The secret to getting this tedious job done quickly is to use many different grits of sandpaper, just as if you were sanding wood. Our lapping system uses a set of five double-sided plates made from laminated MDF. Each is the size of half of one sheet of standard sandpaper.

1. Cut the blanks (El) to final size.

2. Flatten both faces of each plate by sanding them on the top of your tablesaw (Photo 2, page 68).

3. Spray the plates with three or four coats of clear lacquer. Sand the lacquer smooth.

4. Tear your sandpaper into halves and coat each piece very lightly with a spray adhesive, such as 3M Super 77. Apply the paper to the lapping plates (Photo 3, page 68). When your sandpaper wears out, simply peel it off the plate and stick on a new piece. Clean off adhesive residue from the plates with mineral spirits.

Suggested Grits for Lapping Plates

Ordinary sandpaper works fine for most grits, but for the finest ones go with special microfinishing paper, with grit sizes measured in microns (see Sources, page 110). Each lapping plate has two grits, one on each side. Coarse: 100 and 120 Medium: 150andl80 Fine: 240 and 320 Extra-Fine: 400 and 600 Superfine: 15 micron and 5 micron.

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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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