Kerfing

■ I ran into a problem as I was building the frame for the top of the Patio Table (page 6). The frame sections of the table top are mitered then joined with splines that fit in kerfs. But they're not just any splines — these splines are Vfc" thick and 441 long. Which means cutting some pretty serious kerfs. (I used a V'i'-wide dado blade set to cut 2" deep.)

With that much blade exposed I wanted my hands in a safe position, but still in control of the workpiece. The jig I came up with securely supports the workpiece as it runs vertically along the rip fence. It also prevents chipout at the back end of the cut.

making the jig. Two of the pieces needed to make this jig are cutoffs from the already-

mitered frame sections. The other two parts of the jig are simply plywood strips that hold the jig together and create a "pocket" for the workpiece.

To make the kerfing jig. glue the two plywood sides to the mitered cutoffs with a third cutoff temporarily held in place as a spacer, see Fig. 1.

i slngthe jig. To cut a kerf on the end of a mitered workpiece.

first raise the saw blade to the desired depth. Then position the jig against the rip fence and adjust the fence so the blade is roughly centered on the thickness of the jig, see Fig. 2.

To ensure the kerfs are centered on the thickness, cut each kerfin two passes. Justturn the jig around backwards for the second pass (without removing the workpiece), see Fig. 3.

GLUE PLYWOOD SIDES TO FRAME CUTOFFS

SO BLADE IS -CENTERED ON JIG

FRAME SECTIONS

SUDE JIG ALONG FENCE TO CUT KERF

GLUE PLYWOOD SIDES TO FRAME CUTOFFS

SO BLADE IS -CENTERED ON JIG

SUDE JIG ALONG FENCE TO CUT KERF

TEMPORARY SPACER FROM FRAME CUTOFFS

FRAME SECTIONS

HOLD WORKPIECE TIGHT TO TABLE, AND JIG TIGHT

TO FENCE ON EACH PASS

HOLD WORKPIECE TIGHT TO TABLE, AND JIG TIGHT

TO FENCE ON EACH PASS

ROUTER BEARING TRACKS

■ After rounding over the Patio Table frame (page 9). I noticed a shallow "track" left by the router bit bearing, see Fig. 1. A line of wood fibers in the soft redwood had been compressed.

I've seen this on other woods, and on plywood with softwood inner plies. (Sometimes it's not obvious until finish is applied.)

preventing a track. One way to prevent a track with a handheld router is to use an edge guide, see Fig. 2. The wide edge distributes the pressure more evenly so the bearing doesn't press into the wood.

Note: When using an edge guide, adjust the guide so it's flush with the bearing.

removing a track. If vou can't avoid a router bearing track, there's a simple way to remove ¡L And it doesn't take a lot of extra sanding, either.

Restore the compressed wood fibers to their original shape by using a damp cloth and ahotiron, see Fig. 3. Steam causes the fibers to swell back to surface level.

To steam out a bearing track, put the damp cloth on the affected area of the workpiece. Then, with a medium heat settting, slowly run the iron over the cloth.

Keep the cloth damp and check the wood often to avoid scorching. Then, once the track is raised, sand the workpiece smooth as you normally would.

ROUNDOVER BIT WITH PILOT BEARING

BEARING LEAVES LIGHT "TRACK" OF COMPRESSED WOOD FIBERS

ROUNDOVER BIT WITH PILOT BEARING

EDGE GUIDE DISTRIBUTES PRESSURE MORE EVENLY THAN PILOT BEARING

CLOTHES IRON

HOT IRON ON DAMP CLOTH

RAISES COMPRESSED FIBERS

DAMP CLOTH

WORKPIECE

CLOTHES IRON

DAMP CLOTH

WORKPIECE

HOT IRON ON DAMP CLOTH

RAISES COMPRESSED FIBERS

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