Coved Insert Panel

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Fig. b The Height Board

This is simply a scrap of plywood about 8 in. x 12 in., with a pencil line along one edge to mark the maximum height to which you will raise the blade. This height is the depth of the coved profile. For a panel that will be flush with the top of the door frame (the common arrangement), you simply measure from the top of the frame to the groove.

top of frame-

Locate the center of your saw arbor. Mount the centering board on the arbor as if it was the saw blade, and clamp the height board to the rip fence, with the bottom edge at the level of the saw table. Raise the arbor of your saw until the top of the centering board is at the line on the height board. Mark where the arbor line meets the height line.

height board centerline zero-clearance insert

Transfer the centerline from the height board to the ^¡■ii zero-clearance throat plate.Then raise the blade to the maximum height you will be using, while the zero-clearance throat plate is clamped down.

Transfer the centerline from the height board to the ^¡■ii zero-clearance throat plate.Then raise the blade to the maximum height you will be using, while the zero-clearance throat plate is clamped down.

First, Set Up Your Saw

The actual cutting of the panels is fairly straightforward; you clamp a fence at an angle to the saw blade and pass the panels over the blade, taking shallow cuts. But to get perfect results, you need to set up the fence accurately. We've developed a guaranteed system:

1. First, build the auxiliary fence (Photo 3) and make the centering and height boards (opposite page) that you'll use to set the location of the fence.

2. Find top-dead-center of the blade using the centering board and height board (Photo 1). It's important that the fence be located over top-dead-center so the tongue of the panel is properly shaped to fit the groove in your frames (see Oops!, page 40). This is difficult on many tablesaws because the blade actually swings forward as it is raised. You need to find top-dead-center at the maximum height to which you will be raising the blade, because that height will give you the profile you want.

3. Transfer the location of top-dead-center to your zero-clearance insert (Photo 2). Raise your blade through the zero-clearance insert if you haven't already.

4. Position the fence on the tablesaw so it covers the front half of the blade, where the teeth point down toward the table (Photo 3). The blade must be down. Use your miter gauge to set the fence at 35 degrees. The edge of the fence must be directly over the intersection of the blade kerf and the top-dead-center line on the insert (below). Clamp the fence securely to the saw, and you're ready to make a panel.

3 Clamp a shop-made fence to your saw using the miter gauge to set its angle to 35 degrees. (See page 40 for other options.) The fence edge should be directly over the intersection of the centerline on the insert and the blade kerf (at left).

This is how the edge should look after two passes front and back. At this point the coved profile on the back of the panel is complete, so mark which sides of the panels you want to be the front and back.

Cut the Coved Profile

Now that your fence is set, it's time to actually cut the panels. Here's the process:

1. Raise the blade 1/16-in. above the surface of the tablesaw and cut the end-grain of the panel (Photo 4). Note that the panel is being pushed "uphill" against the fence. Cut the long grain and repeat the process on the other side of the panel.

2. Increase the height of the blade 1/16 in. and make another pass on all four edges of both faces, end grain first. Now the back of the panel is complete (Photo 5).

3. Finish the front of the panel by continuing to raise the blade 1/16 in. per pass. Use test cuts on the scrap piece to monitor your progress. It will take about six passes to complete the profile on the front.

4. Measure the thickness of the panel tongue (Photo 7). Leave it 1/32-in. thicker than the groove in the frame to allow for sanding. Dial calipers are an accurate and convenient way to take this measurement.

4 Always machine the end grain first, using a push block to hold the panel.The blade should only protrude l/16-in. above the table. Cut all four edges of both sides of the panel twice, taking off no more than 1/16 in. at a time.

This is how the edge should look after two passes front and back. At this point the coved profile on the back of the panel is complete, so mark which sides of the panels you want to be the front and back.

elt will take approximately six passes in all on the front of the panel to achieve the final shape. Stop cutting when the edge of the panel (the tongue) is the correct thickness (Photo 7).

7 Measure the edge of the panel carefully. To allow for sanding, it should be 1/32-in. thicker than the groove in the frame.

Sand the Profile

To sand the saw scratches out of the profile without spoiling its shape and crisp edges, you need a sanding block that's made to fit the profile. An easy way to do this is with Bondo-type auto-body filler (Photo 8).

When you sand the profile, start with 80-grit sandpaper and move up to 220 grit. When the panel is fully sanded, it should easily slip into the door frame without rattling around inside it.

SAdd a handle to the sanding block while the filler is wet.This makes it a lot easier to hold the block when you're sanding. When dry, the filler creates a sanding block perfectly formed to the cove.

ffi m Sand the cove, starting with 80-grit sandpaper Jf I and moving up to 220 grit. Every so often, check the fit of the panel, to be sure you're not making the tongue too thin.

Attach sandpaper to the sanding block. Self-adhesive sheets are the easiest, but you can also use self-adhesive discs, cut in half.

0Make a sanding block that's the exact shape of your coved profile. Mix auto-body filler and pack it into the cove, with a layer of wax paper over the wood to prevent it from sticking. A piece of scrap creates a dam to hold the filler in place.

Attach sandpaper to the sanding block. Self-adhesive sheets are the easiest, but you can also use self-adhesive discs, cut in half.

Tips

For Great Coved Panels t/ Raise the blade in small increments; 1/16 in. at a time. Light passes make these cuts easier on your saw and provide the smoothest surface.

l/ Have on hand an extra panel, of the same dimensions and thickness as your good ones. Use this for test cuts as you machine the panel.

Imagine the Possibilities

Now that you understand the technique, the possibilities are limitless. The look of the cove changes with every change of blade diameter and fence angle.

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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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