Tesla Cannon

There are not enough fingers on the hands (and on the legs) to count all the fantastic books, films and games, where the energy weapon appears. Admit it, each of you wanted to get hold of a similar thing, so that with ominous laughter, roast enemies with multimeter artificial lightning. Comrade with the nickname Rob was no exception, and under the impression of the comic book The Five Fists of Science gathered his own Tesla gun.

The weapon did not become an exact copy of the cannon from the comic book, but it compares favorably with its literary prototype in that it actually exists. And working!

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At the heart of the gun lies, as you probably guessed, Tesla's resonant transformer . The simplest version of it is used - in the spark gap (SGTC - Spark Gap Tesla Coil).

Housing

The body is made of aluminum by sand casting. As a model for the form was used a children's gun (Nerf Swarmfire).

After casting, a rather rough surface is obtained, so the casing was machined on a CNC milling machine to achieve a perfect match between the casing halves.

High voltage arrester

The heart of the Tesla coil is a high-voltage switch, the role of which in this case is the uncontrolled spark gap. The current in the pulse reaches thousands of amperes, so you need to choose materials that are resistant to enormous temperatures and have good electrical properties.

The body of the arrester chamber was made of porcelain. First of all, a form was printed on a 3D printer.

The form was filled with a ceramic mass, and after a couple of days of air drying, the parts went to the kiln for firing.

Tungsten welding electrodes were used as the electrodes of the discharger. During operation, air will be continuously blown through the discharger chamber using a fan to cool the electrodes and extinguish the electric arc.

Power supply

The gun is powered by a 18-volt lithium battery from a screwdriver. Low voltage is applied to the converter, which raises it to 20,000 volts. The converter is made by a push-pull circuit with switching at zero voltage ( ZVS - zero voltage switch).

The circuit is placed in a plastic cap for sewer pipes.

As a step-up transformer used from the line of the TV.

Battery capacitor

Another essential component of a Tesla coil is a storage capacitor bank. The battery is assembled from capacitors 942C20P15K-F 0.15 µF 2000 V, 6 pieces in series. Each is shunted with a resistor to equalize voltages and to safely discharge after shutdown. For capacitors had to make a separate plexiglass housing. Body parts are laser cut.

Coil

The primary winding consists of five turns of high-voltage wire, and is closed with two milled covers made of high-pressure polyethylene (LDPE).

The secondary winding is wound on a 2.5-inch ABS plastic pipe and contains 1,100 turns of wire with a diameter of 0.25 mm (30 AWG). Outside, the winding is coated with an aerosol polyurethane varnish, and the lower part is additionally insulated with fluoroplastic tape.

The coil is crowned with an aluminum torus providing the secondary winding capacity needed for resonance. It is from him that lightning will strike. Finally, a few photos of discharges: