Making a Slip Joint

The best single illustration of the horizontal router table's capabilities is to make a slip joint.

The slip joint is a simple variation on the mortise-and-tenon; it's really a slot-and tenon joint, sometimes called an open mortise-and-tenon, a bridle joint, a saddle joint. It's a good joint for simple door frames, face frames, and the like. It offers more glue area than any other joint you could substitute. AND it is truly easy to set up and cut. To do it on the horizontal muter table, all you need is a single bit and a sled. Layout work is as simple as layout work can ever be.

The process of routing the slot is a paradigm for slotting the edges of long, wide boards, for routing dovetail slots, and for other similar operations. Making the tenon for the slip joint is no different from making a tenon for a mortisc-and-

tenon joint. This process is a paradigm for routing wide rabbets. and even for routing moldings and raising panels.

1. Set up to cut the slot. In the ideal—and probably-unachievable—setup, the slot is exactly the width of the cutter. If you subscribe to the Rule of Thirds, use a '/»-inch straight bit for making the joint in ^t-inch stock.

Here's the extent of the layout work. On a sample of the stock make two marks, dividing the thickness into thirds. It doesn't have to be perfect; use a ruler if it comforts you to do so. Set that piece on the saw table, and set up the router.

Fit the bit in the collet. Raise the swing arm enough that the bit is up where you can see it. Adjust the bit extension first. Put the piece of stock against the swing arm. and adjust the router so the bit projection is a hair greater than the width of the stock. Now adjust the bit height by moving the swing arm. Set the stock beside the bit. and align the bit between the layout marks.

2. Cut a test slot and fine-tune the setup. Lay the stock flat on the saw table, its end butted against the swing arm. Bring the sled up behind it, then back the stock's end away from the swing arm. You shouldn't try to hog out the full-depth slot in a single pass.

Switch on the router and cut the slot. Keep the sled squarely against the swing arm. Feed the work into the bi;. cutting a slot about '/» inch deep. Pull the sled and work back and shift the work about '/* inch closer to the arm. Make a second pass. Pull back, shift the work toward the arm, and make a third pass. Continue this routine until the slot has re-ached full depth.

Now roll the workpiece over and make a full-depth pass. This will probably widen the slot, but it definitely will center it on the workpiece.

Switch off the router and examine your cut. As long as the slot walls are ho inch thick or better, your setup is okay.

3. Cut the slots. Using the multipass procedure described in Step 2, cut the slots in all the workpieccs.

4. Revise the setup to cut die tenons. Unlock the swing arm and lower the bit. lay a slotted piece beside die bit and visually align the cutting edge of the bit with the slot wall. You want to make a cut that matches the wall's thickness.

Do NOT alter the bit extension.

5- Cut a test tenon and fine-tune the setup. Cut a tenon and a test piece of the working stock. Orient die stock and sled as you did for cutting the slot. Feed the work in the same way. Cut one side, then roll the stock over and cut the second.

Test the fit of the tenon in a slot.

It is that simple. Use the jaekserew for these adjustments. Remember that the change is doubled because you cut twice to form the tenon (and keep it centered).

Loosen the locking knobs and turn the jackscrcw. Tighten the knobs. Cut a new test tenon (or recut the first one if it was too thick).Test the fit in the slot. If necessary, adjust the bit height again and cut a third test piccc.

6. Cut the tenons. When the setting produces a tenon that fits the slots perfectly, cut tenons on the working stock.

Routing the slip joint's slot produces smooth, square surfaces. Back up the workpiece with the sled. Cut the slot in three or four passes. Hold the work-piece back from the swing arm. so the first cut is only % to '/f inch deep. Move the workpiece closer to the arm on the second pass, as shown here, and butt it against the arm for the third pass. Then roll the work piece over, and, with the workpiece butted to the swing arm. make a Final pass to center the slot.

The typical tenon can be routed quickly on the horizontal router table. The amount of material being removed is modest, so a single pass can complete a cheek-and-shoulder cut. For a slip joint, two passes completes the tenon. For a mortise-and-tenon joint, a tenon can be completed in four passes, a speed that matches any other approach. The cheeks will be smooth, the shoulders square.

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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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