Hand Routed Mortises

Basically, a mortise is a deep stopped groove. If it weren't for the depth, the mortise would be really easy to do. But the job takes a straight bit to its outer limits in many cases.

Consider the width of mortise you'd be most likely to cut in y»-inch-lhick stock: 'A inch. Check out the cutting length of Winch straight bits in your bit catalogs. The longest I've found is 1 inch. Now if that bit has a '/»-inch shank, you are going to be limited to its 1-inch length because of the transition from cutter body to shank. If the bit has a 14-inch shank, and it's long, you will be able to cut deeper than the length of the cutting edges. That means you could rout a mortise lVfe or 1 Vi inches deep, maybe even IYa inches deep if you really press your luck.

The cut, expecially that initial plunge, puts a lot of stress on a slender shank. You have to make incremental cuts, which puts the job in the province of the plunge

To make router-cut tenons fit into router-cut mortises, you can round-over the tenon edges with a file or rasp. Especially on a '/*■ to Yn-inch-thick tenon, the job takes only a swipe or two on each of the tenon's four edges.

router. Don't take bites that arc too big, or you'll snap the cutter from the shank.

Can you do the work with a fixed-base router? Of course, but it would involve a lot of fiddling around. If you have more than one mortise to rout—and what project would involve only one?—you will have to adjust the depth of cut between passes. With a lot of routers, that can result in fairly inconsistent mortises—different depths, uneven walls, slightly different widths. The alternative is to make a first pass on each mortise before adjusting the bit height, then make a second pass on each, then a third, and so on. An incredible amount of clamping and unclamping.

If you don't have a plunge router, do the job on the horizontal router table.

Mortising Setup

Here are the typical challenges in cutting a projectful of mortises with a hand-held router:

• Positioning the router consistendy from mortise to mortise

• Providing adequate bearing surface, so no cut is compromised by a router tip or wobble

• Minimizing the workpiece handling

How well you meet these challenges will dictate how well your mortises will turn out.

A blind mortise located at the end of a stile has one distinct weakness: that Yt inch to Vi inch of end-grain stock between the end of the mortise and the stile's butt end. It's fragile, so easy to pop out if you lever the tenon during assembly.

Every woodworker has trouble with this. The traditional solution is to add extra length to the stile. The extra length bolsters that weak spot during mortising and assembly. After the glue is dry and the clamps arc off the assembly, you simply trim the extensions flush with the rails. An extra Yt inch at each end of the stile is all that's needed.

Positioning the router. The easiest way to position the router is using an edge guide. This common router accessory slides along an edge of the work and positions the bit in reference to that edge. (You don't have to reference the work edge, of course. You could fit the work into some sort of holder and reference an edge of it.)

To set up the edge guide, you first have to layout one mortise with a square and pencil. Then you need to transfer the extremities of the mortise to each of the other workpieccs. The edge-guide setting will position the monise laterally, but the markings will allow you to begin and end each monise at the concct places. Just set the workpicces together and square the lines across the lot of them.

Chuck the bit in the router. Set the depth of cut, then set the router on the marked-up workpiece. Position the bit over the monise layout; you probably will want to plunge the bit down to the stock, so you can be sure it is aligned within the layout lines. Set the edge guide, and

frame for panel

ble leg and apron

table leg amd narrow apron below a drawlr

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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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