Shop Notes

AVOIDING STEPPED MORTISES

•A good way to cut mortises is on a router table. But if you use a non-plunge router there may be a problem. You could end up with small steps in the mortise, see photo. These steps can give you a poor glue surface and a loose fitting joint.

With non-plunge routers, you will usually have some play in the height adjustment mechanism. This means that each time the height is changed, the bit

Make the first pass with the spacer in position

Make the first pass with the spacer in position

Set bit to full height isn't in the exact same position it was before. And when routing deeper mortises, where it takes a couple of passes to reach the full depth, you end up with one or more steps.

The good news is, you won't need to buy a plunge router. Instead of changing the height of the bit, change the height ofthe workpiece. Simply lay a spacer, made of V4" hardboard (Ma-sonite), under the workpiece to raise it so the bit cuts less stock.

To cut mortises with a spacer, first set the height of the bit to cut the full mortise depth, see Fig. 1. Then, install the spacer and make your first pass, see Fig. 2. Nowbeforeyoumakethe second pass, remove the spacer, see Fig. 3. Since you aren't adjusting the router height, the bit stays in the same location, and you don't end up with a small step in the mortise.

Set bit to full height

A After changing the height of the bit, somerouters may leave a small step in the mortise.

3

Remove spacer and make the second pass at full depth

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MAKING STRAIGHT CUTS BETWEEN PROFILES

•When you look at the base of the walnut cabinet (featured on page 6), you might expect the ogee profiles are the hardest parts to make. But making the straight cut between the two profiles is more of a challenge.

There's nothing tricky about cutting out the profiles. You just follow the layout lines with your band saw (or sabre saw) and then sand them smooth. But this won't work when cutting along the layout line that separates the two profiles.

Here, the goal is to have a line that's perfectly straight. If your blade wanders even a little, it's easy to see. So I don't try to cut right to the line. Instead, I'll cut on the waste side of the layout line leaving about Vie" of stock.

Then I switch to a flush trim bit in my router table to rout up to the line. But to get a straight cut, you have to guide the bit. To do this, I use double-sided car pet tape to "clamp" a straightedge flush with the layout line, see Fig. 1. Now the bearing on the bit follows the straightedge to rout a straight line, see Fig. 2.

You'll have to stop short ofthe the profile because the diameter of the bit (Vi>") won't let you get into tight corners. But it's simple to finish the cut. Just use a chisel to clean up the corner. Note: I left the straightedge in place to help guide my chisel.

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