Crackle, Spark, and Flash!
The classic high voltage generator - with limited current for safe experiments! For many people this machine is the most vivid memory of their physics classes at school. Everybody is fascinated by the crackling flashes of lightning that appear between the electrodes when the crank on the back is turned.
Two counter-rotating acrylic discs with aluminium segments produce static electricity of up to 70,000 volts that is stored in two Leyden jars made from PVC and aluminium foil. The Leyden jars are discharged via two spherical electrodes, producing bright sparks. The capacity of the Leyden jars is limited by design, so that the produced electricity is completely harmless (rather like the light electric shock one receives sometimes when touching a door knob).
A fantastic kit!
This electrostatic induction machine was invented in 1880 by James Wimshurst (1832 - 1903). Wimshurst was an English naval engineer and inventor, who developed a special interest in electricity and how to produce it. His machines were the first to make possible continuous currents at very high voltages. These were necessary for the first x-ray machines, for example.
An Electric Amusement
Other electrostatic generators had been used since the early 1700s to amuse members of high society, for example with the "electric kiss": the gentleman who dared to kiss a charged lady was payed back with an electric shock.
Harmless Voltage
The AstroMedia Wimshurst Machine can produce voltages of up to 70,000V and sparks of 5 cm length. Nevertheless, it is completely safe to touch the machine. The capacity of the two Leiden flasks is small enough so that the energy of the discharges is well below the legal limit.
Safety First
Never use the machine in the vicinity of flammable fluids or gases. The sparks could cause an explosion. Children should not operate the machine without adult supervision. Although the sparks can not cause any physical harm, they might nevertheless frighten a child unexpectedly.
This kit contains:
- 11 pre-cut and printed A4 sheets of construction cardboard and paper
- 1 pre-cut sheet of aluminium foil, A4, self-adhesive
- accessories:
2 sheets of PVC foil, 105 x 297 x 0.3 mm, transparent (Leiden bottles)
2 discs of acrylic glass, 210 mm (OD) x 6 mm (ID) x 2 mm, transparent (lamellar discs)
4 wooden spheres, Ø 10 mm, with half hole Ø 5.3 mm (spherical electrodes)
2 wooden spheres, Ø 20 mm, with half hole Ø 5.3 mm (spherical electrodes)
2 wooden spheres, Ø 20 mm, with through hole Ø 5.3 mm (ball electrodes)
2 wooden round rods, Ø 5 mm x 45 mm (ball electrodes)
2 wooden round rods, Ø 5 mm x 180 mm (ball electrodes)
2 perforated discs made of pressed cork, 19.5 mm (OD) x 4 mm (ID) x 5 mm (ball electrode holders)
1 rubber shrink sleeve, Ø 6, 4 mm x 140 mm, black (ball electrode insulation)
1 wooden round bar, Ø 5 mm x 40 mm (crank handle)
2 bent parts made of spring steel wire, 119 x 47 x 2.5 mm, cross-section Ø 2.5 mm (current collector electrodes)
1 acrylic glass crossbar, 190 x 20 x 4 mm (insulating crossbar)1 metal threaded rod, M4, Ø 4 mm x 106 mm (running axle)
4 metal washers, 15 mm (OD) x 4.3 mm (ID) x 1.5 mm (running axle)
2 metal nuts, M4, 7 x 3 mm (running axle)
1 aluminium tube, 6 mm (OD) x 4 mm (ID) x 84 mm (running axle)
1 aluminium tube, 6 mm (OD) x 4 mm (ID) x 127 mm (drive shaft)
5 discs made of rigid PVC, 20 mm (OD) x 6 mm (ID) x 1 mm (bearing running axle and drive shaft)
2 O-rings made of NBR, 9 mm (OD) x 4.5 mm (ID) x 2.5 mm, black (drive shaft)1 braid made of copper, tinned, 2 x 150 mm, cross-section Ø 0.75 mm (collector brushes)
1 terminal block, 6-pole, 57 x 17 x 20 mm, white (collector brush holders)
4 metal cardboard nails, Ø 2.5 mm x 30 mm (equaliser electrodes)
2 rubber rings, Ø 90 x 5 x 1 mm, black (drive belts), also available separately as replacements - detailed construction manual
Dimensions of the built model: approx. 24 x 19 x 28.5 cm
Construction time: approx. 15 hours
Producer: AstroMedia GmbH, Im Wirrigen 30, 45731 Waltrop, Germany, astromedia.de
Below you can download the instructions for this kit.
Things you need for a successful assembly:
- a firm and flat working surface
- a set square
- a sharp craft knife or a scalpel
- scissors
- a good universal glue
- some super glue in gel form
- some fine sandpaper
- some adhesive tape
- a pin
- two rather small and preferably pointed combination pliers
- a small screwdriver
- a few clothes pegs
Adult supervision:
Children under the age of 14 should use the kit and the built model under adult supervision to avoid risks due to improper handling.
Take care with small parts:
Choking hazard! Keep small parts out of the reach of small children.
Risk of injury:
Take particular care when handling pointed and sharp parts! Use sharp tools with care and take suitable safety measures to avoid injury.
Fire and explosion hazard:
Keep away from naked flames and heat sources. Product contains highly flammable materials. Components of the kit can release harmful substances when burnt. Never operate in the vicinity of flammable liquids and gases, as sparks may occur.
Avoid contact:
Avoid direct contact with electrical parts during operation. Spark discharges are not dangerous due to the low amperage, but can be painful.
Commissioning:
Do not use in the vicinity of sensitive devices. High voltage can damage electronic devices. Warn people with pacemakers, as high voltage can be potentially dangerous even at low current levels. If necessary, ventilate the room after commissioning, as flashovers can cause ozone formation.
Adhesive use:
Observe the manufacturer's safety instructions when using adhesive. Work in well-ventilated areas and avoid skin or eye contact.
Intended use:
The kit should be used in accordance with the enclosed instructions. Independent modifications may impair the functionality and safety of the model built.
