The history of making fire at will is a long and storied one, stretching back to the days when we’d rub wooden sticks together, or use flint and steel to ignite tinder. An easier, albeit vastly more expensive and dangerous alternative came in the 19th century when chemists discovered auto-ignition using a potassium chlorate mixture and sulfuric acid. This method was refined and later patented by Samuel Jones in 1828 as the ‘promethean match’ after the God of Fire, Prometheus, which is the topic of a recent [NurdRage] chemistry video.
Using practically the same recipe of potassium chlorate and sugar as in the 19th century, [NurdRage] uses paper straws to contain this powder. Glue is used to section the paper straw into two compartments and seal in the components, with the smaller compartment used for a glass capsule containing sulfuric acid. This vial was produced from the tip of a glass pipette, using a hot flame to first seal the tip, then detach and seal the other end of the tip, resulting in the sulfuric acid capsule, ready to be added to the second compartment.
The moment this glass capsule is crushed, the sulfuric acid will soak into the paper, reaching the large compartment with the potassium chlorate and sugar mixture, causing a strongly exothermic reaction that ignites the paper. Yet as simple as this sounds, [NurdRage] found the three matches he made to be rather fickle, with one igniting beautifully after crushing the capsule with pliers, while one did nothing and the remaining match decided to violently explode rather than burn.
Considering the immense manual labor involved in making these matches, they never were very popular, and were quickly replaced by strike-anywhere matches, followed by safety matches, none of which require you to carry fragile glass capsules containing sulfuric acid with you. As a chemistry experiment, it is however a total blast that will set any boring chemistry class on fire.
The first thing to set up, after the hardware and OS, is the network configuration. Each Pi needs a static IP in order to communicate properly. In this case, [Dino] makes extensive use of SSH. From there, he gets to work installing Prometheus and Grafana to use as monitoring software which can track system resources and operating temperature. After that, the final step is to install Ansible which is monitoring software specifically meant for clusters, which allows all of the computers to be administered more as a unit than as four separate devices.
This was only part 1 of [Dino]’s dive into cluster computing, and we hope there’s more to come. There’s a lot to do with a computer cluster, and once you learn the ropes with a Raspberry Pi setup like this it will be a lot easier to move on to a more powerful (and expensive) setup that can power through some serious work.
There were plenty of projects and products to be seen at the 2015 World Maker Faire. In the maker pavilion, we found [Rocco Tuccio] showing off Prometheus, his PCB CNC router. Machines like this make prototyping circuits easy. Just place a blank piece of copper clad in the machine, load up your design, and a few minutes later you’ll have a board ready to stuff. Prometheus sports some impressive specs: 7 mil (0.18 mm) trace and space, and a Total Indicated Runout (TIR) of .0001 inches (2.5 micron). Not bad for a spindle turning 40,000 RPM. [Rocco] has spent the last two years designing this machine, and has sourced most of the parts from local US vendors. The unique part of Prometheus is the spindle design. Like many other small PCB routers, Prometheus uses a brushless quadcopter motor for power. Rather than go with a belt system, [Rocco] simplified things to a simple friction drive. The only precision parts he has to worry about are the bearings which hold the cutting bits in place. Prometheus isn’t for sale yet. [Rocco] plans to launch a Kickstarter campaign in the coming months.
A few minutes later we ran into [Victor Aprea] from Wicked Device, showing off the Air Quality Egg V2. [Victor] and his partner [Dirk] ran the design and manufacturing side of the Air Quality Egg, which had a successful Kickstarter campaign back in 2012. The eggs from that campaign can be found online at the project’s website. [Victor and Dirk] have greatly improved on the Egg since then. The biggest update are the sensors. Sensors for ozone, nitrogen dioxide, and sulfur dioxide are now much more sensitive units from SpecSensors. These sensors don’t come cheap though. To keep costs down, [Victor and Dirk] have released three separate versions of the product with different sensor suites. On the connectivity side, the egg is now based upon Wicked Device’s Wildfire, allowing it to connect to WiFi networks. These Eggs mean business too – [Victor and Dirk] obtained permission to co-locate a trio of eggs alongside an official New York State/EPA air quality sensing unit. The Eggs all read within 2 parts per million for carbon monoxide, and 10 parts per billion for sulfur dioxide. As with the original Egg, these devices are open source hardware. Source code is available on Wicked Device’s Github.
[Everett] is at it again with Prometheus, an arm mounted flame thrower.This is the third generation of the project and makes some huge advances over the second generation we saw last year. We’d say he’s reached cinema/stage-performance quality with his design.
The self-contained system is completely arm mounted with a fuel reservoir mounting behind the elbow. The new version adds an adjustable flow valve actuated by a servo motor to regulate the flame size. An arc generator has been incorporated to replace the lighter from the last version. A microcontroller measures wrist angle and takes care of creating the arc and regulating the fuel supply.
Prometheus is small, controllable, and frightening. See a full demonstration as well as some video of the prototyping process after the break. Does this make you wonder how much burn cream [Evertt’s] needed over the years?