Scroll saw

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Dremel scroll saw

A scroll saw is a small electric or pedal operated saw useful for cutting intricate curves where a jigsaw or coping saw is not appropriate. It is somewhat similar to a band saw, but unlike band saws, where the sawblade is a continuous loop, scroll saws use sawblades similar to those used by coping saws and operate through a reciprocating up and down motion.

There are many different brands of scrollsaws on the market today. Notable ones include Excalibur (made in Canada), RBI (made in the USA), Hegner (made in Germany), Eclipse (made in the USA), and DeWalt (originally made in Canada, but now made in the Far East). There are also a number of less expensive scroll saws made in the Far East including: Delta, Dremel (Bosch), Craftsman, Ryobi and others.

There are different types of scroll saws. The most common design is the parallel arm in which a motor is attached near the back of the arms, and the two arms always remain parallel to each other. The C-arm has a solid "C" shape with the blade being mounted between the two ends of the "C". The parallel link, used by Excalibur and DeWalt, has rods in the upper and lower arms that are "pushed" by the motor to move short (about 4 inches – 100 [millimetres]– long) articulated arms and the end which hold the blade. The rigid arm scroll saw, which was very popular up until the 1970s, but is no longer made, has a single-piece cast iron frame. The blade is attached to a pitman arm on the bottom which pulls the blade down, and a spring in the upper arm pulls the blade back up again. This resulted in a significant weakness in that tension on the blade changed with every stroke of the blade. Modern scroll saws are all "constant tension" saws. Uncommon and larger industrial type scrollsaws, included spring or vacuum sprung scrollsaws, these variations didn't have arms. Instead they had the reciprocation mechanism at one end of the blade and a tension device on the other to return the push stroke, their advantage being the tension/spring device could be hung from the ceiling of a building and large parts that otherwise could not be cut on arm-style scrollsaws could be cut, eg. aircraft frames of the past.

[edit] Blades

Scroll saw blades come in many different types. With the exception of blades made for very light duty saws, typical blades are five inches long. The major types are:

Skip tooth (or single skip tooth) which has a tooth, a gap then another tooth;
Double skip tooth (two teeth, a gap then two teeth);
Crown or two-way which has teeth facing both up and down so it cuts on both the down-stroke (as with all other blades) and on the up-stroke; and
Spiral blades which essentially are a regular flat blade which is twisted so that there are teeth sticking out on all sides.
Metal cutting blades using hardened steel;
Diamond blades (a wire coated with diamond bits) for cutting glass.

Blades come in many different sizes ranging from #10/0 for making jewelry (about the size of a coarse hair) to #12 which is like a small band saw blade. There is also a variation called Reverse Tooth blades. On Reverse Tooth blades, the bottom 3/4" of the teeth are reverse (point up). This helps to clean out the sawdust and also cleans up the tear-out on the under side of the wood. Reverse tooth blades are especially useful when cutting softwoods, and plywood such as Baltic birch plywood.

[edit] Scrollsawing resources

There is a scroll saw organization called the Scrollsaw Association of the World (SAW). Scroll saw magazines include: Scroll Saw Woodworking & Crafts and Creative Wood Works and Crafts. There are also dozens of scrolling pattern books, and several companies which sell scrolling patterns. These can be located through the SAW website. There are also scrolling discussion groups on Yahoo Groups.

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Intarsia, Fretwork, Compound cutting, 3-D cutting, Large Fretwork Clocks, Marquetry and Inlay and Antique Scroll Saws