Cracks Splits

Sometimes a crack will develop on a glue joint after the project is complete. Wood filler isn't the answer— there's a better way.

■ It's not unusual to see an edge-glued table top—or any project—split apart because of wood movement caused by changes in humidity. Here's how I handle the problem.

First I cut the split panel apart right through the crack. This relieves any built-up stress on the crack line. Then I glue the pieces back together and clamp them tight.

I would not use wood putty in a situation like this — putty won't expand or contract like the wood. And if the wood does expand later, the putty can be forced out of the joint

Steve Curtis Shop Manager

putty. Instead, continue the crack with a machine cut. Then re-glue the two edges.

There are two ways to repa ir a crack. If the On a larger panel, a hand-held router with router bit possible. Then re-glue andclamp panel is a manageable size, Steve uses the a straight bit works just as well. To min- the boards back together. If the panel has to table saw to rip through the split joint line, imize the loss of material, use the smallest be the same width, add a wood *'filler" strip.

TOOLS, TECHNIQUES & JIGS

Router Table Tips

How many times have you started to work on a router table and wondered which way to feed the workpiece? Or how fast to feed it? When I'm about to use the router table, I stop and think about these two questions.

feed direction. The most important thing in using a router table is to always have control of the workpiece. And the way to do this when routing an edge is to feed the workpiece into the rotation of the bit — not with the rotation, see Fig. 1.

Since the bit is spinning counterclockwise, feeding the workpiece from right to left (into the rotation) causes the bit to pull the workpiece against the fence, see Fig. la.

If you're not using a fence, and the bit has a bearing on it feeding the workpiece from right to left has the same effect — the bit pulls the workpiece against the bearing.

backroiting. Feeding the workpiece from left to right, called backrouting, can be disastrous, see Fig. 2. When backrouting the bit can grab the workpiece, push it away from the fence or bearing, and out of your hands. Or, if you're still hanging onto the workpiece. pull your fingers into the bit.

another danger. Another technique that's just as dangerous is placing the work-piece between the bit and the fence, see Fig. 3. If you're routing from right to left the bit will grab the workpiece and pull it (and your fingers if they're still holding on) right on through the bit and send it flying out the other side of the router table.

sijOts & grooves. One thing I like about using a router table is it cuts a cleaner slot or groove than a table saw. But when routing a slot or a groove, there is one thing you must always keep in mind — if you widen the groove, always make sure the bit is cutting on the edge of the groove closest to you, see Fig. 4a. This way, the bit is safely pulling the workpiece into the fence.

If you rout the other edge, the same thing will occur as when placing the workpiece between the bit and the fence, the work-piece (or your hands) will get pulled through the bit feed rate. A normal tendency when using a router table is to be cautious and feed the workpiece slowly. But, if the workpiece is fed too slowly the wood can burn.

The best way to determine if the wood is going to burn is to rout a piece of the same type of wood before you rout your actual workpiece. 0 use a piece of scrap from my project.) Then, once you've got an idea what feed rate it will take to get a clean cut rout the workpiece at the same rate.

ijght passes. Another technique to reduce burning (and increase control) is to rout the profile in two or three passes, raising the bit or moving the fence slightly between passes. This technique helps reduce chipout as well.

BIT ROTAnON

FRONT EDGE OF ROUTER TABLE

NOTE:

FEED WORKPIECE FROM RIGHT TO LEFT

BIT PULLS WORKPIECE TOWARDS FENCE

FRONT EDGE OF ROUTER TABLE

NOTE:

FEED WORKPIECE FROM RIGHT TO LEFT

BIT ROTAnON

BIT PULLS WORKPIECE TOWARDS FENCE

FEED

DON'T ROUT WITH WORKPIECE BETWEEN Bn AND FENCE

CUTTER GRABS WORKPIECE

BIT ROTATION

DON'T ROUT WITH WORKPIECE BETWEEN Bn AND FENCE

FEED

FENCE

CUTTER GRABS WORKPIECE

Oooo

BIT ROTATION

Homemade Tenon Jig Plans

IT'S OKAY TO ROUT A SLOT OR GROOVE BECAUSE BIT IS BETWEEN FENCE AND WORKPIECE

INWARD PRESSJRf:

FENCE

FIRST PASS

SECOND PASS

BIT ROTAnON

SLOT OR GROOVE

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