Page 21 - 15 Dangerously Mad Projects for the Evil Genius

2 15 Dangerously Mad Projects for the Evil Genius

WARNING! What You Will Need

This is not a real gun. You could probably throw the The components for this coil gun are all readily
projectile as fast as it comes out of the end of the available. It’s worth shopping around for the
gun. In addition, the projectile is lightweight.
capacitors; eBay usually has a good selection of
However, this project has a number of dangerous suitable ones if you search for “electrolytic
aspects.
capacitors.” You’ll need the parts in the Parts Bin.
High currents. These are not high voltages, but
You will also need the following tools listed in
the currents are very high and produce strong
the Toolbox.
magnetic fields, so do not build this project or use
it anywhere near anyone with a pace-maker.
T OOLBO X
Do not short-circuit the capacitors when they are
■ Soldering equipment
charged up. You may melt whatever you are
■ Hacksaw
shorting them with, which means there will be small
quantities of molten metal flying around. ■ Wood saw
■ Drill and assorted drill bits
And do not place your eye or anyone else’s in
■ Epoxy resin glue or hot glue gun
the line of fire of this gun.
■ Multimeter

P A RT S BIN

Part Quantity Description Source
Firing tube 1 Disposable transparent ballpoint pen about
5 ⁄16 of an inch (7mm) in diameter
Coil retainers 2 Plastic brackets cut from a plastic food
container (see the following description)
1
Projectiles 2 Iron/steel nails ⁄8 inch (3mm) Hardware store
Lumber 18 inches (45cm) length of ⁄8" × 1 ⁄4" Hardware store
1
5
(18mm 33mm) wood
Plastic drink bottles 1
Plastic insulating tape Hardware store
Coil wire 13 feet (4m) of 20 or 21 AWG enameled copper wire Farnell: 1230984

Batteries 4 Budget PP3 9V batteries
Battery clips 4 PP3 battery clips Farnell: 1183124
C1-8 8 4700μF 35V electrolytic capacitors, or any set Farnell: 9452842
of 35V capacitors totaling around 38,000μF eBay
SCR 1 40TPS12A Thyristor 55A Farnell: 9104755

S1 1 DPDT On-off-momentary toggle switch Farnell: 9473580
R1 1 100 2W Farnell: 1129029
R2 1 100 0.5W Farnell: 1127903
D1 1 5mm Red LED Farnell: 1712786
R3 1 2.7K 0.5W Farnell: 9338667
D2 1 5.1V 5W Zener diode Farnell: 1705663