Problem Solver

Trying to adjust your router setup so the mortise is exactly positioned on the workpiece is difficult and often frustrating. A better focus for your attention is marking each workpiece so the mortises will be consistently positioned.

Example: You rout mortises in the stiles of a framc-and-panel cabinet door. The mortises aren't quite centered on the stile edges. The tenons are centered, so when assembled, the faces of the rails and stiles aren't flush. A typical solution is to sand the assembled frame to bring the faces flush.

But because you referenced the back face for one mortise and the front face for the other, the faces of the assembly aren't parallel. One end of the rail is proud of the stile's back face, and the other end is proud of the front face. See Twisted Frames. Moreover, the panel will have to be twisted slightly to fit into the groove for it. The assembly is more likely to warp.

REFERENCE FACE HOT MARKED» RAIL UIOJ ON OWE SIDE.LOW ON THE OTHER. FLATTENING THE FRAME WILL REQUIRE. A LOT OF

TWISTED FRKMLS: ON BOTH 5)013. FRAME IS PLAT.

WJIL rn BRINOUC, RAIL FLUSH REOJIRLS OWtY

prevention is better tu&n a cure MODEST SAMDIMG

TWISTED FRKMLS: ON BOTH 5)013. FRAME IS PLAT.

WJIL rn BRINOUC, RAIL FLUSH REOJIRLS OWtY

prevention is better tu&n a cure MODEST SAMDIMG

RkVDOM MftAUGHMENT GCTWllX MORTISES O-O TENONS PROOUCES A TWISTED FRAME.

REFERENCE FACE HOT MARKED» RAIL UIOJ ON OWE SIDE.LOW ON THE OTHER. FLATTENING THE FRAME WILL REQUIRE. A LOT OF

and though sanding will improve its appearance, it just won't be totally satisfactory.

If the mortises are consistently closer to one face or the other, the misalignment is a whole lot easier to cure with a little planing or sanding. The planes of the rails and stile will be parallel, so the panel will be flat.

So mark a reference face on each of the pieces to be mortised. Lay out :he pieces as they'll be assembled. Mark the face that's up. When you rout the mortises, always have the reference face oriented the same way. The mortises may not be perfectly positioned, but all of them will be the same.

Doing this will require two slightly different setups for a full firame-and-pancl job. For example, if you rout the mortises on the horizontal router table, you have to shift the location of the work-piece positioning stop. Rout one mortise on each stile, then move the stop and do the other mortise.

each piece, move the locating stop so you can do the second mortise in each and still keep that reference face properly oriented.

The rail-mortising sled is a mutation of the stile-mortising sled. The fence is parallel to the bit axis rather than perpendicular to it. Its construction is virtually the same as the other sled. Align the fence as shown in Stile-Mortising Sled.

Setup and use of this jig also mimics the other sled. Set the guides to govern the side-to-sidc movement but also to position the mortise in the workpiece. A good way to set up

To keep the reference face up,you need to relocate the positioning block for the second mortise on each stile. Do this only after all the stiles have one mortise cut in them.

BIT DRAWER

The bit of choice for excavating mortises is the upcut spiral bit. This is the router bit that looks a lot like a twist-drill bit.

There are several reasons you want to use this bit. First of all, it's a true plunge-cutting bit. It's designed to bore straight down into the work, cutting a clean hole. In addition, it has an augering action that moves the chips sliced from the workpiccc; the upcut configuration moves them up and out of the mortise. Finally, a spiral bit has both high hook and shear angles, so it doesn't take a lot of horses to power one. Nevertheless, it slices smoothly through wood and cuts aggressively.

A second-choice bit for mortising would be an upshear straight bit. This won't auger the chips from the cut so efficiently as a spiral, but the upshear flutes still slice the wood rather than scraping it. The cut is still smooth without requiring major horsepower.

The last choice—the one used more often than not, unfortunately—is the common plunge-cutting straight. It does the job. and if that's what you have, don't be deterred from mortising. It won't clear the chips, and consequently, it'll run hotter.

In selecting a bit for mortising, look for the longest one you can find. The cutting length is less important than the overall length. You'll be trimming about Y♦ inch at a time as you plunge deeper and deeper into the mortise, so the cutting is being done at the rip of the bit. A long cutting edge isn't particularly useful. A long shank, however, is essential to reach into thai deep mortise.

EAGLE AMERICA H"UPCUT SPIRAL BIT

MLCS W UPCUT SPIRAL BIT

Usually we advise you to use the '/2-inch-shank version of any bit. This is the exception. For mortising, try to match the shank diameter to the cutting diameter. A Winch cutter should be on a Winch shank. A Vs-inch cutter should be on a Vfc-inch shank (assuming you have cither a Winch collet or a reducer for your router). The reason is that deep reach.

A Winch cutter on a Winch shank has a transition—often an abrupt one—from the cutting diameter to the shank diameter. Usually the transition is right at the end of the cutting edges. When it contacts the work, the transition will chamfer the edges of the cut just a little and bum the wood quite a lot. You just can't get the bit to cut deeper than its cutting length.

The bit I like to use for Winch-wide mortises is this 2 Winch-long

EAGLE AMERICA H" UPCUT SPIRAL BIT

upcut spiral from MLCS. The cutting length is 1 inch, but its Winch shank will reach nicely into the cut, so I can, with care, plunge about lYi inches into a mortise with it—and still have at least Yt inch of the shank in the collet. This is a solid carbide bit, so you can't be too aggressive. It will break.

For mortises Ya inch wide, 1 use Eagle America's Jit-inch solid-carbide upcut spiral. The cutting length is 1 Yi inch, and it's on a Winch shank, so the cutting length represents the maximum cutting depth.

Once you get to the Winch diameter, there are a lot of long-shank bits available. Eagle America has a 4-inch-long spiral, and even though the cutting edges end at 1 Vi inches, the shank will get those edges 2Yi inches or more into a mortise.

Setting up the rail-mortising sled should he done with a marked workpieee clamped to it. Raise and extend the bit. Align the bit with layout marks made on the face nf the workpieee. Move the edge guide against the table-top edge and tighten the setscrews.

Chair-making frequently involves cutting angled mortises. It's easy with the rail-mortising sled. Cut a wedge or spacer and stick it to the sled base beside the fence. Then the rail is clamped in place for mortising.

Setting up the rail-mortising sled should he done with a marked workpieee clamped to it. Raise and extend the bit. Align the bit with layout marks made on the face nf the workpieee. Move the edge guide against the table-top edge and tighten the setscrews.

Chair-making frequently involves cutting angled mortises. It's easy with the rail-mortising sled. Cut a wedge or spacer and stick it to the sled base beside the fence. Then the rail is clamped in place for mortising.

:he jig is to lay out the ends of the nonise on the face of a workpieee. Clamp it in the jig: with the mounting board set high (so the bit is above the work), align the bit with rhe marks, then set the guides.

To cut a mortise, plunge-cut the ends to the full depth, then nibble away at the waste in between, cither with additional plunge cuts or by working the sled side to side, cutting a bit deeper with each pass.

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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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