The Explodium is a power supply used for purposes of Mad Science. The first version, the Mark I, was no more than a microwave oven rewired. Since then it has been the subject of many upgrades and improvements to become a safe, reliable means of generating very high current discharges.

No video or images were produced of the early experiments. It was only after the first upgrade that the group decided to name the construction the 'Mark III,' in reference to it being the third configuration to be tested. Since then, each significent design alteration has increased the number.


Mark III

Bulb go boom.Mark III saw a substantial upgrade: The replacement of a 1uF capacitor with a 100uF. You can get so much on eBay. A 100W 230V bulb was used as a test object, at 2KV. The bulb didn't last very long.


Mark IV

The Mark Four: Voltage doubled microwave transformer, one kilojoule cap at 4KV.

Mark IV

The Mark IV improved upon the Mark III by adding a new pneumatic switch. Safety considerations limited the Mark III to no more than two kilovolts: Any more was judged too dangerous to be anywhere close to, even at the length of the hot stick. With a new pneumatic switch, far higher voltages and energies can be used without endangering the operators: Pneumatics ensures complete electrical insulation even at voltages a hundred times greater than the equipment is intended to produce.

The use of a voltage doubler raises the output to four kilovolts (approx - exact measurement not yet possible), and the addition of three more capacitors holds a kilojoule. A single test was performed on a grape. Although the grape was instantly destroyed, the demonstration proved overwhelming to both the camera and the diodes. As each 'diode' was actually six diodes in parallel each rated for a surge of 60A, this is quite concerning.


The Mark V was intended to add resistors in series with the (replacement) diodes to protect them and to enclose more of the high-voltage equipment. This was a dismal failure: The first charging resistor proved too high, and when removed even the new over-speced diodes burned out. Worse, the camera was knocked out of place and recorded only the ceiling and puff of smoke! However, from the remains it was possible to determine that the diodes failed due to a reverse bias far, far in excess of what they were rated for. The only source of such a potential would be inductive, so plans were made to add three huge relays to isolate the charger completly before discharge. Relays good for isolating ten kilovolts or more are not common, but ebay can provide so much.

Though a failure, the Mark V design was able to discharge once. The test material used was a pokemon card dampened in vinegar. Though most of the energy was wasted in destroying the diodes, enough made it to the card to cause some damage. The markings left by the paperclip contacts are visible, along with a noticeable fading of the dye. As this is present only in the current-carrying regions, it cannot be attributed to a chemical effect of the vinegar. The most likely explanation is destruction of the dye by heating.

Fire-type does not resist electricity.

Mark VI

Mark VI schematic.

Mark VI solved the serious design flaw of the Mark IV and V: Failure of the voltage doubler diodes due to very high voltages resulting from inductance within the discharge wires. This was solved by adding three relays which completly isolate the transformer and diodes from the capacitor bank. This is when the schematic starts to get complicated. A second control is required for the charging system - rather than a pneumatic link, this is a simple microswitch with a piece of string attached. This small switch in turn operates a set of relays: Two (shown on the diagram as just one for simplicity) connect the AC supply to the transformer, while another three (Likewise shown as one for simplicity) are used to isolate the voltage doubler from the capacitor bank. This was a huge success. A fuse with a 20KA rupture current was not just blown but entirely obliterated leaving nothing but the end caps and a cloud of ceramic, while a PC speaker experienced such force on the voice coil that it was ejected at considerable velocity. The equipment took no damage from either of these, and was even able to achieve our first can crush with nothing more serious than a few melted wires and a banana plug welding into place - problems that can be easily solved with nothing but thicker wire. The next improvement was planned to be a less unweildy and improvised control system than relays and string, and the enclosure of components for protection and safety.

No video survived from the speaker test. The mobile phone was too close to the high-current wire, and crashed as a result of the magnetic field. We also required some improved recording equipment - the video quality from a mobile phone is not good, and the audio even worse.


Mark VIb

Mark VI: Session two. No changes were made this time, just additional testing performed - work continued, but the new control system was far more complicated electronically and took more time to complete. We did have access to an old DV camera that records at a full 25FPS so some jerky slo-mo was possible. After three shots, the bank ceased to function due to a failure of the pneumatic switch contact.


Mark VII


These are our hazmat suits. They are made of hazmat.

Mark VII was intended to add a new control system. Installation of this was delayed by the Olympics - with police rumored to be conducting random anti-terror searches on public transport, it was judged too dangerous to transport a box of homemade electronics and wireing that may be mistaken for a bomb. Instead a new chamber was added to contain shrapnel. A sandblasting chamber modified to stand on end.

With this, we could finally achieve one of our great plans: The fastest ever scrambled egg.

The blast chamber. Splat.

Session two


11/12-08-12

With the olympics still delaying the installation of the new control box, there was time to refine the equipment further. Most importantly, this meant the use of a new high-speed camera. A Praktica DVC 10.10 FHD. Not a dedicated high-speed camera, but a budget low-cost video camera that happens to support a 240FPS mode. A true high-speed camera remains prohibatively expensive - but the Praktica can perform acceptably, even if limited to a very low resolution and with evident sensor noise. Like all high-speed cameras, high illumination is essential - for this, we used a 400W security floodlight.

432x240 at 240FPS. It's as good as I could afford.

We also discovered that the equipment was no longer capable of crushing cans. The new blast chamber requires longer connecting cables, and the increased inductance was a serious impediment to the type of ultra-fast pulses needed for electromagnetic crushing efforts. Plans were drawn up to fix this by mounting the capacitors on the rear of the chamber - not just for the reduced inductance, but as a means to render the equipment more compact and less prone to accidential damage.


Session three


02-09-12

The olympics finish, but the paralympics prolong the delay yet again. Still unable to install the new controls, instead we exploded bananas. One new item was added: A Franklin bell, which served briefly as an indicator of charge. Before any video was made of this, an unfortunate malfunction occured resulting in explosive disassembly.



Mark VIII


Mark VIII introduced the control unit first intended for Mark VII. A fibre optic cable to replace the string-and-switch charge control, and in future the discharge and safety relays. With the new controls it was also almost possible to enclose the charge unit entirely in it's own box, both safer and tidier. Almost, but not quite - a few more changes are needed to remove the need for a bulky external supply for the charge isolator relays.

The first session of the MK VIII tested it upon three victims: A pineapple, a tomato, and a can.

Mark VIIIa

Three weeks later, the Mark VIIIa alters corrected the flawed power supply for the charge isolation relays, allowing the charger to be completly enclosed in safe, insulating plastic.

Mark IX


Pneumatics out, spark gap in.


With the design up to Mark IX, we installed the final major component: A trigered spark gap, based on the trigatron design. This completed the most functional aspects: All that remained after that were some finishing details like quick-assembly connectors and a magic smoke extractor.

The first victim of the Mark IX design was a failed CFL. The test revealed a flaw in the design: The spark gap was narrow enough to arc prematurely, before full charge was reached. Even at this reduced energy, the CFL exploded in a most spectacular manner. Unfortunately the premature fireing destroyed the voltage doubler diodes.

We had hoped to run a simulated accident. Many people have asked what would happen were one of us to accidentially touch the high-voltage lines, a possibility we had been calling the 'red mist scenario.' The obvious way to find out would be to connect a suitable analog for human flesh, such as a piece of pork with skin. This experiment was postponed due to the destruction of the voltage doubler.