Retrotechtacular: Making Porcelain Insulators

Here is a silent film produced by General Electric that depicts the making of many kinds of porcelain insulators for power lines. Skilled craftsmen molded, shaped, and carved these vital components of the electrical grid by hand before glazing and firing them.

Porcelain insulators of this time period were made from china clay, ball clay, flint, and feldspar. In the dry process, ingredients are pulverized and screened to a fine powder and then pressed into molds, often with Play-Doh Fun Factory-type effects. Once molded, they are trimmed by hand to remove fins and flashing. The pieces are then spray-glazed while spinning on a vertical lathe.

Other types of insulators are produced through the wet process. The clay is mixed in a pug mill, which is a forgiving machine that takes scrap material of all shapes, sizes, and moisture levels and squeezes out wet, workable material in a big log. Chunks of log are formed on a pottery wheel or pressed into a mold. Once they are nearly dry, the pieces get their final shape at the hands of a master. They are then glazed and fired in a giant, high-temperature kiln.

Continue reading “Retrotechtacular: Making Porcelain Insulators”

Caption CERN Contest – Dr. Frankenstein would be proud

Week 16 of the Caption CERN Contest just flew by, but not without sparking some cosmic comic genius in the minds of everyone who wrote a comment. Thanks to everyone who entered! If you followed last week’s blog post, you already know that this image isn’t an early POV display, or some sort of strange data display technique. It’s actually a spark chamber. Spark chambers use high voltage and noble gases to create a visible trail of cosmic rays. Since this image is dated 1979, well after spark chambers were used for hard science, we’re guessing it was part of a demonstration at CERN’s labs.

The Funnies:

  • “Here we see Doug playing a Massively multiplayer Pong game against his peers in the next building over.” – [John Kiniston]
  • “It said “Would you like to play a game?” and I said yes. Are those missile launch tracks?”- [jonsmirl]
  • “Before Arduino you needed a whole room full of equipment to blink LEDs!” – [mjrippe]

After two weeks as a runner-up, this week’s winner is The Green Gentleman with “‘Hang on, let me fix the vert-hold, and then get ready for a most RIGHTEOUS game of 3D PONG!’ Sadly, this CERN spinoff never made it to the market”

We’re sure [The Green Gentleman] will be very courteous to his fellow hackers in sharing his new Bus Pirate From The Hackaday Store! Congratulations [The Green Gentleman]!

Week 17

cern-17-smCoils, gleaming metal, giant domes, now this is a proper mad scientist image! The CERN scientists in this image seem to be working on a large metal device of some sort. It definitely looks like an electrode which would be at home either at CERN or the well equipped home lab of one Dr. Frankenstein’s. We don’t have a caption, but we do have a rough date of August, 1961. What is happening in this image? Are these scientists setting up an experiment, or plotting world domination?

You tell us!

This week we’re giving away a Logic Pirate from The Hackaday Store.

Add your humorous caption as a comment to the contest log. Make sure you’re commenting on the contest log, not on the contest itself.

As always, if you actually have information about the image or the people in it, let CERN know on the original image discussion page.

Good Luck!

A Scary Powerful Jacob’s Ladder

What to do with an extremely high voltage transformer and power supply… what to do…  what to do… Short it out Jacob’s Ladder style of course! Fresh from [Gristronics], a team of hackers had the opportunity to play around with a 11,000V transformer… and some copper pipe.

It’s 2.5m tall (just over 8′) and produces an awe-inspiring electrical arc. The transformer takes in 240V and spits out 11,000V. To help stabilize it, they’re even using some microwave oven capacitors to act as a ballast. The transformer is affectionately named “Betsy”. They even have a giant contactor (think relay with steroids) to act as the main switch.

During the initial setup, they noticed it wasn’t working very well, so they setup a camera to record at 240fps to see what was going on — turns out the coils were shorting to each other. After fixing the insulation, they got it working consistently — and holy cow is that a big arc.

Continue reading “A Scary Powerful Jacob’s Ladder”

Killer USB Drive is Designed to Fry Laptops

[Dark Purple] recently heard a story about how someone stole a flash drive from a passenger on the subway. The thief plugged the flash drive into his computer and discovered that instead of containing any valuable data, it completely fried his computer. The fake flash drive apparently contained circuitry designed to break whatever computer it was plugged into. Since the concept sounded pretty amazing, [Dark Purple] set out to make his own computer-frying USB drive.

While any electrical port on a computer is a great entry point for potentially hazardous signals, USB is pretty well protected. If you short power and ground together, the port simply shuts off. Pass through a few kV of static electricity and TVS diodes safely shunt the power. Feed in an RF signal and the inline filtering beads dissipate most of the energy.

To get around or break through these protections, [Dark Purple]’s design uses an inverting DC-DC converter. The converter takes power from the USB port to charge a capacitor bank up to -110VDC. After the caps are charged, the converter shuts down and a transistor shunts the capacitor voltage to the data pins of the port. Once the caps are discharged, the supply fires back up and the cycle repeats until the computer is fried (typically as long as bus voltage is present). The combination of high voltage and high current is enough to defeat the small TVS diodes on the bus lines and successfully fry some sensitive components—and often the CPU. USB is typically integrated with the CPU in most modern laptops, which makes this attack very effective.

Thanks for the tip, [Pinner].

11,000 Volt Jacob’s Ladder Sounds Like a Lightsaber

In the high-voltage world, a Jacob’s ladder is truly a sight to behold. They are often associated with mad scientist labs, due to both the awesome visual display and the sound that they make. A Jacob’s ladder is typically very simple. You need a high voltage electricity source and two bare wires. The wires are placed next to each other, almost in parallel. They form a slight “V” shape and are placed vertically. The system acts essentially as a short-circuit. The voltage is high enough to break through the air at the point where the wires are nearest to each other. The air rises as it heats up, moving the current path along with it. The result is the arc slowly raising upwards, extending in length. The sound also lowers in frequency as the arc gets longer, and once [Gristc] tuned his system just right the sound reminds us of the Holy Trilogy.

We’ve seen these made in the past with other types of transformers that typically put out around 15,000 Volts at 30mA. In this case, [Gristc] supersized the design using a much beefier transformer that puts out 11,000 Volts at 300mA. He runs the output from the transformer through eight microwave oven capacitors as a ballast. He says that without this, the system will immediately trip the circuit breakers in his house.

In the demo video below, you can see just how large the arc is. It appears to get about 10 inches long before breaking with a sound different from any Jacob’s ladders we’ve seen in the past as well. Continue reading “11,000 Volt Jacob’s Ladder Sounds Like a Lightsaber”

Low-Voltage Tesla Coil Uses a Relay Instead of a Spark Gap

[Teodor] writes in with a unique Tesla coil he designed and built. Unlike most Tesla coils, [Teodor]’s design is able to run with a fairly low input voltage because it doesn’t use a static spark gap like most Tesla coils. Instead, his coil uses a relay in place of a spark gap.

[Teodor] built his coil using leftover components from his old school, making good use of some parts that might have otherwise been thrown away. The most critical component of his circuit, the relay, is just a standard normally-closed relay that is rated at 20A. [Teodor] wired the relay so that it energizes its own coil whenever it is shut. This causes the relay to briefly open every time the coil is energized, creating a resonant circuit. The resonant circuit charges a tank capacitor and places it in series with the primary coil inductor every time the relay closes, forming the tank circuit of his design.

With [Teodor]’s design, the resonant frequency of the secondary is nearly identical to that of the primary. This creates a significant voltage boost, helping produce very high voltages from such a low input voltage. The only downside to this design that [Teodor] recently discovered is that the relay contacts get red-hot after a few minutes of operation. Not optimal, but it still works! Check out [Teodor]’s writeup for more details and instructions on how to build your own.

3D Printed Wimshurst Machine

Steampunk extraordinaire [Jake von Slatt] has released his latest creation. This time he’s built a Wimshurst machine from mostly 3D printed parts. The Wimshurst machine is an electrostatic generator and was originally invented in the late 1800’s by James Wimshurst. It uses two counter-rotating disks to generate an electrostatic charge which is then stored in two Leyden jars. These jars are also connected to a spark gap. When the voltage raises high enough, the jars can discharge all at once by flashing a spark across the gap.

[Jake’s] machine has a sort of Gothic theme to it. He designed the parts using Autodesk’s 123D Design. They were initially printed in PLA. Skate bearings were used in the center of the disks to ensure a smooth rotation. The axle was made from the fiberglass shaft of a driveway reflector. The vertical supports were attached the base with machine screws.

The Leyden jars were made from sections of clear plastic tube. The caps for the jars were 3D printed and are designed to accept a short length of threaded 1/8″ pipe. Copper wire was used for the interior contacts and are held in place with electrical tape. The metal sectors on each disk were made from pieces of cut aluminum tape.

You may be wondering how this machine works if it’s almost entirely made out of plastic. [Jake] actually painted most of the parts with a carbon paint. This makes them electrically conductive and he can then use the parts to complete electrical circuits. Unfortunately he found this to be rather ineffective. The machine does work, but it only produces sparks up to 1/2″ in length. For comparison, his other machine is capable of 6″ sparks using similar sized Leyden jars.

[Jake] actually tried rebuilding this project using ABS, thinking that the PLA may have been collecting moisture from his breath, but the result is still only 1/2″ sparks. He suspects that the bumpy surface of the plastic parts may be causing the charge to slowly leak away, preventing a nice build up. He’s released all of his designs on Thingiverse in case any other hackers want to give it a whirl.