Thermoelectric power jig saw:
1 — M4 screw, 2 — strip, 3 — nichrome filament, 4 — wing nut M4, 5 — ring, 6 — clip, 7 — power cord 8 — switch 9 — panel, 10 — handle, 11 — tube arc.
The jig saw consists of a tubular arc, handles, electric buttons, nichrome wire, screws with wing nuts, insulating spacers, earrings, and electrical wires.
Arc made of duralumin tubes Ø 12 mm. she Can be of plywood. This detail needs to be lightweight and durable. The handle is made of textolite with a thickness of 10 mm. It has a cylindrical shank whose diameter corresponds to the hole tube arc. The shank is slotted groove for the power wires, the noise inside the tubular arc.
Earring is made of sheet copper with a thickness of 1 mm is fixed on the arc with two screws. To it with a screw with a wing nut is attached to the end of the nichrome wire (heating element). On the handle between the two cheeks made of sheet aluminum, 0.8 mm thick, installed electric button.
As the heating element applied in a spiral electric iron; the most suitable — Ø 0,5 mm. the length of the thread depends on the length of the tubular arc. Nichrome filament is fixed with a certain tension.
On the electrothermal jig saw is powered with a voltage of 12-14 V; when sawing, it is advisable to use a rheostat. The value of the input current depends on the material, length and thickness of the nichrome filament. When specified on the drawing the dimensions of the arc and the diameter of the nichrome filament 0.5 mm current consumption for various materials is 3-5 A.
Before starting work, depending on the type of material used, the rheostat sets the required current. Be aware that when a large current (high temperature fiber) plywood may flare up, and if insufficient heating plexiglass only softened, but not cut.
Jigsaw is simple in design, convenient in operation, allows you to cut (burn) the details of any form.
The disadvantages of the tool should include only what stands out when cutting out the smoke with an unpleasant odor from the treated material.
Work with electrothermal jigsaw requires compliance with security measures: hands should be protected from burns, from the workplace to remove flammable items, the room must be constantly aired.
P. KAPITONOV, Cheboksary
Recommend to read THERMOMETERS WITHOUT MERCURY For the guys from the club for young technicians Novosibirsk Akademgorodok has long been the rule: the work performed in the groups should be of a socially useful nature, contain... CAMERA… OUT OF NOTHING Is it worth to reinvent the wheel? Readers of our magazine have long been convinced that it is worth. Example to the materials published in recent years in our magazine, spoke about the... 
The scroll saw is a common tool. However, when working with him, guys sometimes faced with certain difficulties: the blade breaks, POPs out of the clips, if the cut on a curved path is often twisted, making it difficult to maintain the required direction.