Radial arm saw

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Radial Arm Saw

A radial arm saw is a cutting machine consisting of a circular saw mounted on sliding horizontal arm. Invented in 1923, the radial arm saw was the primary tool used for cutting long pieces of stock to length until the introduction of the mitre saw in the 1970s.

In addition to making length cuts a radial arm saw may be configured with a dadoe blade to create cuts for dado, rabet or half lath joints. In addition some radial arm saws allow the blade to be turned parallel to the back fence allowing a rip cut to be performed.

[edit] Origins

Unlike most types of woodworking machinery, the radial arm saw has a clear genesis: it was invented by Raymond De Walt of Bridgeton, New Jersey. De Walt applied for patents in 1923, which were issued in 1925. De Walt and others subsequently patented many variations on the original, but De Walt's original design (sold under the moniker Wonder Worker) remained the most successful: a circular sawblade directly driven by an electric motor held in a yoke sliding along a horizontal arm that is some distance above a horizontal table surface.

Before the advent of the radial arm saw, table saws and hand saws were most commonly used for crosscutting lumber. Table saws can easily rip stock, but it is awkward to push a long piece of stock widthwise through a table saw blade. In contrast, when a radial arm saw is used for crosscutting, the stock remains stationary on the saw's table, and the blade is pulled through the stock.

Beginning about the late 1970s, the compound miter saw began to replace the radial arm saw somewhat, but only for crosscuts and miter cuts since it is unable to perform rip cuts. The radial arm saw can be less safe when used by an inexperienced or untrained operator, but is not dangerous when used properly. In the hands of an experienced operator, the radial arm saw can safely cut compound mitres necessary for picture and door frames, rip lumber precisely to width, cut tongues and grooves, and make variable dados. Most cuts are followed with a fit and require more material be removed, sometimes a tiny amount (which is easy to do). Like the compound mitre saw, the radial arm saw can make these cuts with absolute precision, but is capable of making a wider variety of cuts, including more complex ones.