Lap Joints and Gauges

The simplest timber joints are lapped notches, just like those used in log buildings. For plain half-laps, you take away half of each timber at the area of overlap. You'll find half-laps at the very bottom of a building in the corners where the sills intersect, and in the very top where the rafters join at the peak.

The laps usually get pegged for security, but as always, the joint carries the load, not the peg.

Half-laps bring equally thick timbers into the same plane, but few timbers are equally thick. If one side of the assembly is more important than the other, this is termed the face side. You ensure that the face side is level by making all measurements from that surface and letting the back side take care of itself.

When using a gauge, the rule is to always gauge from the face side. The gauge is just a small beam with a scratcher set through an adjustable fence, used to mark a line or lines parallel to any surface. For a half-lap, set your gauge for half the thickness of your timbers and run it around with the fence riding on the face sides (say, the upper sides) of both timbers. When the lap is cut to those lines, the face sides of the timbers will be dead level, and any difference in thickness thrown to the back sides.

The face side is not just a matter of appearance. For example, if joists are to receive flooring, then their tops need to be all on the same level. This makes the joist tops the face sides—the side you measure from, the side where the fence of the gauge must ride. If the notches in the top of the plate (the top beam of the wall) have already been cut evenly to the depth of a chalk line, then gauging down from the tops of the joists will ensure that they will sit level with one another. The square or any straightedge will transfer the width of the lower timber onto the upper one, and the gauge gives you the depth of the notch.

The saw defines the shoulders of the joint, making stopping cuts for the splitting to follow. A four-inch-thick, half-seasoned timber makes slow going for a fine-toothed saw. Undignified as it seems, the same bucksaw used for cutting firewood can quickly cut the shoulders of a timber joint. In seasoned, hard timber, however, a coarse saw will jump around, so the teeth have to match the task.

Splitting saves time only if it doesn't weaken the joint or ruin the timber. You can safely split away perhaps two-thirds of a lap joint with a hatchet—more if the grain looks good. The risk is a split that turns deep into the timber, guided by a buried knot. Work your way deeper as you repeatedly turn the timber to work from the other side. After the first big chunk comes out, the smaller waste wood will bend away from the hatchet blade. This bending waste will exert less leverage, and the hatchet's edge will do more work than its wedge.

Of course the other risk of splitting out a joint with a hatchet is striking the wrong spot. Many folks use their hatchet as a broad chisel, setting the blade on the wood and striking the back with a mallet.

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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