Routing Laps

Conceptually, cutting laps is a lot like cutting rabbets and dadoes. Don't reach for the rabbeting bit, though. Laps are usually much wider than cuts we typically think of as dadoes and rabbets. In some cases, a lol wider, and therein lies whatever nib there is. But I'll get to that.

Because of their similarity to dadoes and rabbets, the techniques for routing laps mimic those for cutting dadoes and rabbets. You use some variety of straight bit—straight, shear-cut. spiral, what have you. And you use a guide—a fence, a T-square, a straight template.

The depth of cut necessary makes the plunge router the first choice for this job. The correct depth setting—exactly half the thickness of the stock—can be elusive. To have to monkey around with intermediate depths compounds the frustration. And if you have to repeat the operation to lap both ends of each piece, it can send you over the top. Now if the total depth isn't more than Ys inch, you can probably do it in one pass; the first cut is unavoidably heavy, but as you work back and fonh, widening the cut. you can nibble. But the plunge router is the real solution here. You can set the final depth right at the start, but use two or three intermediate settings before that ultimate depth.

dovetail

HALF-LAP

tue lap joint in many of its variations end-lap t-lap

Mitered Haif Lap Joint

edge-lap end dovetail malf-lap mitered half-lap full lap dovetail

HALF-LAP

tue lap joint in many of its variations end-lap t-lap edge-lap end dovetail malf-lap mitered half-lap full lap

An offset base can help you cut end-laps with a pattern bit. Push down firmly on the outboard knob to keep the hose fiat on the work, ensuring that the lap is a consistent depth. The pattern bit's bearing rides the template, ensuring that you get a crisp, square shoulder cut.

Two T-squares can be used to guide your router in cutting a cross-lap. Use a locat-ingjig to position them from the layout lines. Alternate the crossbars so they don't conflict.

Routing End- and Cross-Laps

The usual technique for laying out end- and cross-laps is to use the work itself. Lay one workpiecc on top of the other, right where they are supposed to be lapped. Scribe along the edges of the top piece, marking the bottom piece. Turn the two over and repeat.

Now clamp a guide of some son to the work, set up the router, and cut. If you are cutting several pieces— end-laps on four sides to a frame, for example—save time by aligning all the pieces, clamping them together, and cutting them all at once.

If you are cutting end-laps, you can use a T-square—along with a T-square locating jig (see 'T-Square" on page 225) to position it—as the router's guide. The end-lap has only one shoulder, so you need only one guide. But you can also use the self-positioning dado guide or, in conjunction with a template guide bushing or a pattern bit. a straight template. (See the chapter 'Template-Guided Work.")

The rumple in the operation is router tippiness. Usually, you make the first pass with the router riding the fence, to establish the shoulder of the lap. Then you make passes back and fonh, working out to the end. For most of the operation, there's suppon for the router on both sides of the bit. But as you make that last pass, you're removing vital support. The router's going to tilt, and the bit's going to gouge the work.

Several possibilities present themselves.

• Lay out and cut the end-laps as cross-laps, thus leaving a ridge of waste to suppon the router. Trim the waste away after the laps arc

An offset base can help you cut end-laps with a pattern bit. Push down firmly on the outboard knob to keep the hose fiat on the work, ensuring that the lap is a consistent depth. The pattern bit's bearing rides the template, ensuring that you get a crisp, square shoulder cut.

Two T-squares can be used to guide your router in cutting a cross-lap. Use a locat-ingjig to position them from the layout lines. Alternate the crossbars so they don't conflict.

CUT TOO DEEP

CUT JUST RIGHT

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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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Responses

  • Mikael
    Can straight bits cut half laps?
    1 year ago
  • jayden
    How to use a router for half lap joints?
    3 months ago

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