The sliding dovetail is ideal for joining a breadboard end to a glued-up panel, like a tabletop or chest lid.
The breadboard end, which is simply a narrow strip of wood, is a traditional method for preventing wide, glued-up panels from cupping. It is attached across the panel's end, concealing the end grain. The breadboard end prevents the cupping, but because its grain direction is perpendicular to that of the panel, it introduces a new problem: It has to be attached in a way that allows the panel to expand and contract, as wood is wont to do.
The sliding dovetail does this. You plow a dovetail groove in the breadboard and cut a tail across the end of the panel. Slide the breadboard end onto the tail, and drive a nail or dowel through the assembly, roughly at the center, locking the two pieces together. The breadboard end can't pop off the tail, but the panel can expand and contract.
The tough pan is achieving the appropriate fit. Glue can tighten a loose sliding dovetail in a lot of situations, but not this one. If you glue die pans together, you'll defeat the purpose of the joint. Be as precise as you can in the fit. and before assembly, nib some paste-wax on the tail.
The process doesn't change significantly. The bit-height adjustment has the same effect on cither router table. But on the horizontal router table, you adjust the router height rather than adjust the fence. Again, for safety's sake, the cut should be made between the work and the tabletop, so you don't trap the work between the bit and the table.
A couple of fcatherboards clamped to the router mounting board help keep the work flat on the tabletop, in consistent contact with the cutter. These hold-downs can even straighten out minor bowing.
Tightly crafted, it is almost totally hidden: There's a barely discernible scam, and right there, the figure of the wood changes direction sharply. You don't see any end grain. That's the best of iL
The worst is that the simple miter joint is—structurally—a terrible joint. It's sissy weak. If you glue it, you're trying to glue end grain to end grain, a hopeless causc. Run some fasteners into it, and you're running them into end grain, where they won't hold very well. Moreover (when things go bad. they go really bad), the joint is vexing to assemble. Because of the angles involved, a mitered corner always wants to slide out of line when you apply clamping pressure to it.
The solution to all the problems, a solution that doesn't affect the pure, pristine appearance of the miter in any way, is a spline.
A spline is a separate piece of wood.often plywood, that reinforces a joint. Usually, the spline is set into slots in the mating surfaces in such a way :hat the grain of the spline will run across the main joint to resist splitting along that joint. This placement just happens to be ideal for holding the pieces in place for gluing, too.
The question is how to cut the slots in the right places. There arc several answers, and all involve the router as the cutting tool. The main reason that there are several answers, which arc spread out on these pages, is that there's fair variety among miters. How many can you list? Here arc three main groups:
• Flat miters, in which the angled cuts run across the faces of the pieces
• Edge miters, in which the pieces to be jointed are actually beveled rather than mitered
• Compound miters, in which the picces are cut with combination miter and bevel cuts
Each kind of miter joint requires a slightly different approach to cutting the grooves for the splines—a different router table fence, perhaps, or a different router fixture. Within each group, it's possible to isolate variations that require a change of approach.
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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.