With Chip Out and Tear Out

It's a hazard of routing rabbets. As the bit cuts, it tends to tear wood strands (tear-out) and lift chips (chip-out) along the edges of the cut. Tear-out seems to happen most along the shoulder of the cut. while chip-out occurs along the bottom edge. The explanation is depicted in the drawing.

When you arc feeding the router in the proper direction, chip-out occurs as the cutting edge of the bit sweeps off the wood. Because the cutting edge is almost perpendicular to the work's edge, it's cutting end grain as it exits. With nothing backing them up. the outer wood libers tend to be forced out from the cut, and they break and split. Often the splitting extends below the base of the case, taking chips out of the cut's bottom edge.

In a climb cut. the cutting edge is sweeping into the wood, forcing the wood fibers in so there arc no chips lifting out. But you are feeding with the bit's rotation, and the router wants to gallop ahead, even if it has to pull you along.

Tear-out is influenced by grain direction rather than feed direction. If the grain is straight and your cut is paralleling it. the cutting edge sweeps easily and cleanly. But if the grain bows and shifts and cuds, the cutter tends to bring up shavings that don't get sliced off but instead curl up along the edge of the wood. It's the same

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problem you have planing wood with shifting, changing grain directions.

Most experienced router woodworkers have settled on some approach that—if only in their minds—minimizes these tendencies. The most common approach is to rout the full rabbet in two or more passes, and to make one of those passes a climb cut—cutting with the rotation of the bit. rather than against it. There are two schools of thought here. One says you make the first pass a shallow climb cut—this is often called a scoring cut. The other says you make the second pass the climb-cut.

In theory neither pass needs to be a climb cut. The drawing shows how a shallow first pass will alter the angle between the cutting edge and the work's edge at the exit point. Chip-out is minimized if the cutting edge is skimming the edge, slicing along the grain rather than chopping across it. The second pass should be the deep one.

Hold on to the router if you do make a climb cut. The bit will grab and jerk the tool along the cut, and it can startle you if you aren't expecting it. The caveat to hold on applies doubly when doing this on the router table. If the bit grabs the work, it can jerk it out of your grasp, not inconceivably resulting in injury (and a botched workpiecc).

great job. Use the largest-diameter bit you have—however big it is—to producc those wide rabbets.

As the cut gets wider—wide to the point that you have to make three or four passes to complete it—avoiding wobbles and dips is the challenge. On the router table, you have to keep the uncut surface of the piece tight against the table. And if the ultimate cut is wider than the remaining uncut surface, then the last pass or two can be dicey. Pressure on the wrong area of the work can cause it to tip, gouging it. Doing the cut with a hand-held router isn't likely to be any easier.

One solution is to treat the rabbet as a wide dado or groove. Cut the work with some excess width or length (whichever is appropriate).

By supplanting the pilot with a fence,you can greatly increase the width of the rabbet you can cut with the router. Here, the rabln't matches the diameter of the bit. But by adjusting the fence away from the bit, the rabbet could be made even wider.

TO CUT A WIDE RARBET.CUT THE WORKPIECE OVERSIZED.

WITH A UAND-HIlP ROUTER

By supplanting the pilot with a fence,you can greatly increase the width of the rabbet you can cut with the router. Here, the rabln't matches the diameter of the bit. But by adjusting the fence away from the bit, the rabbet could be made even wider.

Leave a ridge of unrouted stock at the outer edge of the cut. This will support the router or the work. After the router cut is done, you trim the ridge of waste away on the tabic saw. reducing the work to its final width and simultaneously turning the dado into a rabbet.

An alternative is to use double-sided carpet tape to stick a couple of shims to the router table at the fence after making the first pass. The shims will support the workpiece as you make subsequent passes.

Another approach is to deal with the rabbet as a deep cut. Address the depth of the rabbet with the fence or edge-guide setting, and

TRICKS FOR CUTTING WIDE. RABBETS

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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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