Woodworker's Journal 1992-16-5, страница 47

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in. wide stock. The arm and stop are made from '/- in. thick stock.

The lengths of the fixed and sliding fence parts w ill be determined by the width of the platform. However, they shouldn't be any shorter than the 20 in. and J8⁷/s in. lengths, respectively. Whatever the platform width, make certain that the sliding fence is 1 '/k in. shorter than the fixed fence.

Once the fence, arm and stop parts have been cut lo length and width, establish the various holes and slots. The slots are all cut on the router table using a straight hit that 's equal to the slot diameter. with stopblocks clamped to the router table fence to index where the slots will start and stop. Don't try to make the slots in a single pass. Instead, make the slot in . a series of passes, raising the bii about in. for each subsequent cut until the slot is complete.

As shown in the exploded view, the Via in. wide by 11¹/- in. long slot in the fixed fence starts 5'/- in. from the end of the fence that's flush with the base edge that kisses the saw blade. Also eul the slots in the pivoting fence, locking arm and adjustable stop. Note thai there'-- a second slot. V⁴ in. wide by 'A in. deep, cut into the inside face of the pivoting fence. This oversize slot, which is cut with a 'A in. diameter router bit, serves as a counterbore so the head of the bolt thai holds the stop in place doesn't protrude, a siluation that would be a problem when I he jig is used as a cutoff lable. When drilling the various bolt holes, note that the two holes through Ihe sliding fence and the single hole through ihe pivoting fence are also counterbored.

Mortise the sliding and pivoting fence parls for the hinge (It. then make small rabbet cuts inlo the fence parls and slop, as a relief area to prevent sawdust buildup between the fence parts and platform, and on the inside corner where the pivoting fence and stop meet. Finally, you may want to add a sandpaper surface to the working face of the pivoting fence. The sandpaper (which should be glued in place with a spray-lvpe adhesive thai would allow for easy

September/October 1992

paper replacement | serves to provide some extra support to keep stock from creeping when the jig is being used for tapering or miteinig

Fence Assembly

Locate and mount ihe fixed lence to the

Bill ol Materials

(all dimensions actual)

No.

Part Description Size Req'd.

No.

Part Description Size Req'd.

' Width ol base, and length of fixed and sliding fence pans will depend on the size ol your ^rJw table, but should not be less than Ihe sues indicated. If the distance on your saw table from the blade to the left edge of the table measures less than 18 in then increase the width of the end runner to a dimension that, when added to the distance from the blade to the table edge, will total 20 in. Thickness and width of mrter gauge runner is sued to fit your miter gauge slot

platform. Don't assume lhat the back edge of the base is automatically square to the blade edge. Instead, use a large square (such as a framing square) to set the fixed fence at an exact right angle to the base edge that kisses the blade. Then use glue and countersunk screw s lo permanently fasten the fixed fence to the base.

Join the sliding and pivoting fence parts with ihe hinge, insert ihe V/2 in. long carriage bolls (L. M) and mount the locking arm, then mount the stop to the pivoting arm, and the sliding fence to the fixed fence, using the remaining carriage bolts (J, K).

Setting the Scale

As shown in Fig. I, you'll want to scribe a scale on the locking arm, making index marks for. al the very least, the mast common angles. We've scribed index marks at 15, 30, 45. 60 and 75 degrees, but you can add more if you wish.

Here's how to locale the various points on the locking arm. First, using an adjustable triangle, a machinist's protractor. or fixed triangles, set the adjustable fence to each desired angle, and lock it m place. One by one, at each specific angle selling, scribe an index mark vertically on the edge of the locking arm, so it aligns with the top edge of the sliding fence. Use a combination square as a guide to scribing these index marks, lo insure that they are straight. You can write in the angle at each scribe mark on the locking arm, or use a set of number punches, as we have, lo stamp the numbers into the wood. Given the length of the locking arm. if you are reasonably accurate in making the index marks, this jig will yield superior accuracy compared to using your tabic saw's miter gauge angle settings.

Finishing Up

As mentioned earlier, don'l sand surfaces. However, the back edge of ihe fixed fence should be gently rounded, since this is where your hands grasp the jig. No finish is needed, though you may want to rub in a little penetrating oil to give the piece a finished appearance.

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