Try This

Before cutting good wood, test your dcpth-of-cut setting on scrap. Since a lap cut removes half the thickness of the stock, you need to make pairs of test cuts. Do the initial setting with a ruler. Snick the comer of your scrap, flip the scrap over, and snick a second comer so the two cuts just intersect, as shown. If the depth of cut is too shallow, the two cuts won't connect. If it is too deep, you'll see that. Keep adjusting and testing until the two cuts just merge.

CUT TOO DEEP

CUT JUST RIGHT

The trick in cutting end-laps with a hand-held router is supporting the tool squarely. If you cut the workpieces overlong and leave a band of full-thickness waste, the laps are in effect cross-laps. Here a T-square is clamped to all four workpieces. The first pass is made with a spacer between the router and the T-square (left). With the spacer removed, the shoulder cut can be made with the router against the T-square, then any intervening waste routed away (right).

One way to support the router while cutting end-laps is to leave a band of waste, which you trim off after the laps are completed. But how can you be sure you're cutting them long enough?

Use a spacer cut to the width of the lap between the fence and the router base.

Set up the work, clamping together all the parts to be machined, with scrap pieces on the outsides. Clamp your fence to the work to guide the router and position the shoulder cut. Cut your spaccr.

Set up the plunge router, and make the shoulder cut first, making as many passes as necessary

The trick in cutting end-laps with a hand-held router is supporting the tool squarely. If you cut the workpieces overlong and leave a band of full-thickness waste, the laps are in effect cross-laps. Here a T-square is clamped to all four workpieces. The first pass is made with a spacer between the router and the T-square (left). With the spacer removed, the shoulder cut can be made with the router against the T-square, then any intervening waste routed away (right).

to cut to the full depth. Then fit the spaccr In placc—you'll probably need to clamp it, too—and make the end cut, again cutting to the full depth (left). This should leave a band of stock at the butt ends of the workpicccs. Remove the spacer, and rout the waste material from between the first two cuts (right).

routed. You can only do this, of course, if you leave the workpicccs overlong co begin with.

• Clamp expendable rails on each side of the lap. Rout into them, but not through them.

• Stan the cuts at the very end of the piece, and work toward the shoulder. This way you'll have the router half-supported throughout the cut.

• Use an offset router baseplate. (See. for example. "Offset Baseplate" on page 54.) This will work if you use a straight template that guides a pattern bit or a template guide bushing.

• Use carpet tape—you know, the stuff that's sticky on both sides—to temporarily attach a small scrap of the working stock to the router baseplate.

If you are cutting a cross-lap, you need two fences to guide the cuts as well as to limit their total width. You don't need to worry about tipping unless die lap's width is more than half of the baseplate's diameter. (If your router's baseplate is 6 inches in diameter, you can cut a 3-inch-wide lap with a Winch bit and have the baseplate bearing on both sides of the cut at all times.) If the lap is to be wider than that, skim ahead to "Cutting Wide Laps" on page 292.

T-squares will work as fences, as will self-positioning dado guides and straight templates.

Routing Pocket Laps

A stopped lap, a lap that doesn't cut all the way across the face of the workpiece, is known as a pocket lap. You might use pocket laps in a face frame where you didn't want end grain showing on the sides. The lap joint between rail and stile would be hidden on the inside of die cabinet.

The easiest way to cut pocket laps is wit h a U-shaped jig made out of a square of Winch plywood (or hardboard) for the base and several strips of one-by stock for the fences.

To make the jig, do some measuring and easy calculating first.

• Determine the width of the lap.

• Measure the diameter of the router baseplate.

• Decide which bit you'll use to make the cut.

• Add the width of the cut to the diameter of the baseplate.

• Subtract the diameter of the bit.

The result is the distance between the jig's parallel fences. Add the combined widths of two pieces of the onc-by stock, and you have the width of the jig.

Here '$ an example. The lap width is IVi inches. Our Bosch D-handle has a 6Winch-diameter baseplate. We'll use a Winch bit to make the cut:

6K + IVi - V* = 8 So the distance between the fences m ust be 8 inches to get the cut we want with the bit we're using. Add another 3 inches—the combined widths of two pieces of 1 x 2—and we know we need an 11-inch-square piece of Winch plywood for the jig's base.

Cut the base. Make sure the sides are parallel and that they arc perfectly square to the end. Likewise, make sure the one-by stock is straight and square, with parallel edges. Cut one strip 11 inches long and two strips 9Vi inches long.

With 18-gauge nails or brads, nail the long strip along the base's end. Then add the shorter strips along the sides. Drive the nails through the base into the fences.

Secure the bit in the collet, damp the jig to a scrap. Rout the cutout into the jig's base. Push the router into the jig along the left fence. When it hits the back fence, advance the router to the right, then pull it back toward you when it contacts the right fence.

The resulting cutout in the jig base should match the width of the pocket lap you want to make.

The design of the pocket-lap jig allows you to position its cutout directly on the layout lines. The fences should be wide enough to provide clamping space without interfering with the router handles, as shown here. Note that the corners of the pocket match the radius of the bit used to cut the pocket.

To use the jig, first lay out the pocket lap on the workpiecc. Line up the jig with the cutout on the layout lines. Clamp it to the work. Cut the lap the same way you routed the cutout in the jig.

After the pocket is routed, you will need to square the comers with a chisel.

The jig can also be used to cut through laps. Just align it across the workpiece, with the back of the cutout clear of the work's edge.

The caveat about lap width—if the lap's width is more than half the diameter of the router's baseplate, use an oversized baseplate—applies here, just as it did with end- and cross-laps.

Routing Mitered Half-Laps

The mitered half-lap combines the structure of the half-lap with the appearance of the miter. You can't just miter two pieces that have already been half-lapped, of course. One pan of the joint could be done this way, since on the rails, the shoulder cut is square while the butt end is mitered. But on the stiles, the shoulder cut is mitered while the butt end is square.

What you need is a set of three guides or templates. Ideally, you optional positioning fence -attach to fcrftom bt jl4 with screws (so it can &e moveo).

of jig example: used with this jig, a g«»* oia." bastplate. router and v*" mt form a zvt" wide pocket lap, up to fcv»* long.

MAKE. A POCKE.t-L.AP JIG.HEJtES HOW!

optional positioning fence -attach to fcrftom bt jl4 with screws (so it can &e moveo).

of jig example: used with this jig, a g«»* oia." bastplate. router and v*" mt form a zvt" wide pocket lap, up to fcv»* long.

MAKE. A POCKE.t-L.AP JIG.HEJtES HOW!

TRY THIS!

would make these templates to use with a pattern bit. but you can add a router fence to them if you don't have a pattern bit and don't want to get one. One template is a right-angled guide. The others are right-hand and left-hand miter guides. All are made using birch plywood and strips of hardwood. They arc sized to allow you to lap stock up to 5Yi inches wide.

To make the templates, cut three pieces of Winch birch plywood to 7 inches by 13 inches. These are the bases. Be sure they are absolutely square. (The Winch thickness ensures that the pattern bit's bearing will have a reference surface without having to cut too deeply in the work. If your bit's cutting length is 1 inch, a common one, you'll be cut-

Ifyou like the look of profiled molding that meets in a crisp miter, youTI love assembling frames with mitered half-laps. The joint is strong yet easy to rout, and if allows you to unerringly rout a profile on the inside edge before assembly. After assembly, the profile will meet, fair and square, at the miter (right). A joint that must be edge-routed after assembly yields a rounded comer (left).

ting Y% inch into the work with the bearing just barely in contact with the template.)

For fences, cut three pieces of '/2-inch hardwood to lYi inches by 7 inches. The hardwood should be straight-grained and defect-free.

The right-angle template has the fence attached along one 7-inch edge, as shown in Mitered Half-Lap Templates. Use glue and three or four 1-inch screws. For the template to be accurate, the fence has to be perfectly parallel to each base's short dimension and square to its long dimension.

The miter templates have the fences attached along one of the long edges, also as shown. Cut a 45-degree miter across each template. Be sure you locate the fences and cut the

The best way to check the accuracy of the templates of fences is to make cuts and check them.

For the right-angle guide, check a cut made using the guide with a try square. If the cut is slightly out of square, you can sand or plane the edge of the guide that the bearing references.

For the miter guides, mate a saw-cut miter with one trimmed using the guides. Check the joint with a try square, and if it is out of square, sand or plane the reference edge of the offending guide.

miters to create right and left templates; the templates are NOT duplicates. As with the right-angle template, accuracy is essential if the frames you make with them are to be square.

Guides with fences are made pretty much the way the templates are. The biggest change is the addition offences to guide the router. To provide guidance throughout the same range as the templates, you need to make the bases for the miter guides wider.

The router fences can be made of the same material as the other fences. The goal is to have the cutting edge of the bit grazing the guide's edge. To achieve this, position the fences so the bit will trim the base edge on the first pass. You can cut back on the thickness of the base material, of course. Quaner-inch plywood or hardboard is fine.

Again, because accuracy is so important, take special pains to ensure that the fences are placed at accurate angles.

Both the templates and guides are used in the same way. Begin by machining the workpieces. cutting

TO WORK WITH PATTERN BITS , USE THESE MITERED UALF-LAP TEMPLATES

Here's how to use the right-angle guide. Put both rails together and align the guide exactly on the shoulder. One clamp should anchor both rails and the guide. Use carpet tape to affix a support block to the baseplate. Here, the block is made up of a scrap of the working stock and a scrap of '/■finch plywood (the stuff used for the guide's base). To avoid chip-out and tear-out, feed the cutter into the work from all sides.

Here's how to use the right-angle guide. Put both rails together and align the guide exactly on the shoulder. One clamp should anchor both rails and the guide. Use carpet tape to affix a support block to the baseplate. Here, the block is made up of a scrap of the working stock and a scrap of '/■finch plywood (the stuff used for the guide's base). To avoid chip-out and tear-out, feed the cutter into the work from all sides.

a groove or rabbet for a panel, if there is to be one, then routing in that profile—a bead, an ogee, whatever. Now trim the pieces to final length. In doing so, miter the ends of two pieces and square-cut the other two. Usually the rails are mitered. the stiles square-cut.

The rails are lapped across their backs. To ensure they're identical, lap both at the same time, using the right-angle guide. Butt them edge to edge, faces down, and clamp them together. Set the guide in place, its reference edge right on the shoulder-cut line. Clamp it; one clamp should do. Set the router's depth of cut, and have at it. If you are using a pattern bit. an offset baseplate can help eliminate tippiness, which could cause you to gouge the work. With a regular straight bit, a support block attached to the baseplate with double-

WJien routing the stiles, you can orient them as shown, so the guides or templates together support the router.

sided carpet tape is probably the best solution to router tippiness.

With the rails done, turn to the stiles. The stiles are lapped across their faces. Clamp the appropriate guide to each piece and, with the router setting unchanged, rout each lap. Repeat until all are cut.

Router tippiness can be a problem in lapping the stiles, too. but a different solution presents itself here. Try positioning two stiles at right angles to each other, their ends almost touching, each with a guide clamped to it. The router can straddle the guides for sure supportand cut both laps at the same time.

Dovetail Half-Lap

A mechanical lock is offered by the dovetail half-lap. The end-lap can't just slip out of die cross-lap, it's got to be lifted. So it is a stronger joint than the standard half-lap. It has that dovetail look, to boot, so it imparts a touch of class to your frame.

To get these benefits, you have to do a little extra work.

If you have only a couple of these joints to craft, use a saw to cut the tails out of routed end-laps. Then use the tail to lay out the socket for it on the mating workpiecc. Clamp a self-positioning guide or template on each fine, and rout the socket.

However, if production is what you have in mind, a couple of templates can be made to expedite your work. The templates shown require the use of a pattern bit. It's possible to resize them to use with a guide bushing, if that's your preference. (If you switch to wider stock, you'll have to scale up the layouts and make new templates. You can probably make these work on narrower stock, though I won't guarantee it.)

TO WORK WITH STRAIGUT &ITS.USE THESE. MITERED HALF-LAP GUIPES

Finding the right balance between template thickness and your pattern bit's range is critical in cuttingjoinery with templates. Routing the dovetail shape into a half-lap may take a couple of passes if you use a very short pattern bit with a thick template. The first pass is made with the template clamped to the work and the bit cheated out of the collet (left). The bearing rides on the template, while the cutter addresses the worhpiece. To complete the cut, remove the template and reset the bit. The bearing then rides on the surface of the previous cut (right).

Finding the right balance between template thickness and your pattern bit's range is critical in cuttingjoinery with templates. Routing the dovetail shape into a half-lap may take a couple of passes if you use a very short pattern bit with a thick template. The first pass is made with the template clamped to the work and the bit cheated out of the collet (left). The bearing rides on the template, while the cutter addresses the worhpiece. To complete the cut, remove the template and reset the bit. The bearing then rides on the surface of the previous cut (right).

the latter were substantial cuts, and Phil, in the interest of speed, made almost all of them with a radial arm saw equipped with a dado cutter. As you can imagine, the cuts all had the corrugated bouoms characteristic of the dado cutter.

Consider these cuts in terms of the router. With a 6-inch-diameter router base and a Winch bit, a 3-inch-wide la? is about as wide as I'd want to cut. Beyond that, the router will lose its support on one side of the cut. To cut these laps, you need a custom baseplate to bridge the recess you and your router arc creating.

For that 5'/>-inch-widc bp, I'd make a rectangular baseplate a minimum of 12V* inches long, with the router bit at dead center. With a Winch bit doing the cutting, I'd have at least 1 inch of bearing on both sides, even at the shoulders of the cut. Dctemimmg Baseplate Length gives you my formula for determining how long to make the baseplate. Use it to tailor your baseplate to your lap.

Make the bases out of plywood and the fences from a straight-grained hardwood. Cut the bases, but "nine" them before adding the fences.

To tunc the templates, you should use them to cut test joints. If the tail won't go into the socket, do a little trimming on whichever template seems appropriate. If the tail is loose, well, start over. When the templates are tuned, add the positioning fences to the socket template.

To use the templates, cut an end-lap on the piece that's to have the tail. Clamp the tail template to the stock, and use your pattern bit to trim the edges of the lap. Then clamp the socket template in posi-tior. and, again, use the pattern bit to cut the socket.

Cutting VJ'tde. Laps

In designing and building projects for our book Outdoor Furniture, Fred and our colleague Phil Gehrct used lap joints for many of the chairs and loungers. In some applications, the pieces being lapped were 1 inch thick and m inches wide, while in others they were as much as 1 Vi inches thick or 5Vi inches wide. Obviously.

Router Inside Corner Cutting Board
Because the router creates rounded inside corners on the tail,you have to wake your dovetail socket template so it produces outside comers of a watching radius. That's the reason for the goiterlike cutouts on the neck of this tewplate.

rout flashy joinery with these dovetail half-lap templates ■ "

round ours«* corners at

RkPMJS Of 5IT. SO TUEY'LL MATCH CONTOUR OF IUS»9t CORUCRS

tue.lt template} are scaled for use. with a straight patte.rn ®fl on 2vtwi0e stock.

TEMPLATE

rout flashy joinery with these dovetail half-lap templates ■ "

round ours«* corners at

RkPMJS Of 5IT. SO TUEY'LL MATCH CONTOUR OF IUS»9t CORUCRS

tue.lt template} are scaled for use. with a straight patte.rn ®fl on 2vtwi0e stock.

TEMPLATE

In many applications, the half-lap is hidden on the back of the finished assembly. But the dovetail half-lap needs to be exposed. The joint is pretty and strong, and when routed with complementary templates, it's tight yet easy to assemble.

Curting a 5Vi-inch-wide half-lap in Winch-thick stock with a router can be time-consuming. And dirty.

Even though you end up with a clean cut.

Think about it. If you use a y«-inch bit.you need eight passes. Eight passes at each of two depth settings. And every half-lap involves two pieces of wood, so you're cutting a combined recess 5Yi inches wide and 11 inches long. Thai's a lot ofchips inyour lap, as well as a chunk of time out of your work session.

Dc yourself a favor. If you have a stack of really wide boards to lap. rough out those cuts with a dado cutter or on the band saw. then bring them to final depth and pristine smoothness with your router. You won't need as much time, and you won't get quite so much dirt in your lap.

And do this work on the router table. Work from the side or back, so the workpiecc is well supported, and use the fence as a stop.

The real trick in bottom-cleaning a wide lap is preserving the shoulder. If you can mount a bearing on the shank of your bottom-cleaning bit, turning it into a pattern bit, do it. If you can't, tape Fred's dadoing baseplate to the router (see the chapter "Dadoing and Grooving"), and clamp a matching fence across the lap's shoulder, as shown here. This will stop the router at the shoulder.

The real trick in bottom-cleaning a wide lap is preserving the shoulder. If you can mount a bearing on the shank of your bottom-cleaning bit, turning it into a pattern bit, do it. If you can't, tape Fred's dadoing baseplate to the router (see the chapter "Dadoing and Grooving"), and clamp a matching fence across the lap's shoulder, as shown here. This will stop the router at the shoulder.

In many applications, the half-lap is hidden on the back of the finished assembly. But the dovetail half-lap needs to be exposed. The joint is pretty and strong, and when routed with complementary templates, it's tight yet easy to assemble.

To eliminate any possibility that a heavy router could cause this broad baseplate to sag, I'd make it out of '/i-inch plywood.

Using a baseplate this wide means the fences have to be backed away from the cut. Cutting the hypothetical 5'/j-inch-wide lap with my new 12'A-inch-long baseplate means I have to position my fences a very real 23Y* inches apart.

At chis point, I think I'd turn to the template guide bushing. Using the guide bushing would allow me to position my fences just M» inch from the shoulder lines. But because the baseplate is so wide, the fences also would have to be wide—8 inches or so—so that the clamps wouldn't interfere with the baseplate.

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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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