Friday Hack Chat: Playing With Fire

We’re pretty sure all the hackers and tinkerers and makers out there were a tiny bit of a pyromaniac in their youth. That’s what makes this week’s Hack Chat so exciting: we’re talking about Hacking With Fire.

Our guest for this week’s Hack Chat will be [Brice Farrell], who, like most of us, has been interested in fire his entire life. He’s taken this interest and turned his amateur passion into something semi-professional. He’s a PGI certified pyrotechnician, an electrical engineer, and an ice carver. This year, he appeared on BattleBots where he built the flame system for Battle Royale with Cheese.

Given [Brice]’s extensive expertise, this Hack Chat is going to cover the relevant safety concerns of work with fire, how to keep yourself safe, and how to do everything legally. We’ll be talking about fireball shooters of all sizes, ignition techniques, and the use (and introduction) of fire in combat robotics. That last point is extremely interesting: is fire on a BattleBot actually useful, and what can you do to protect your bot from it?

Points of interest for this Hack Chat will include:

  • Fire safety
  • The difference between generating flames and fireballs
  • Ignition techniques
  • Fire safety
  • Fire in combat robotics
  • Fire safety

You are, of course, encouraged to add your own questions to the discussion. You can do that by leaving a comment on the Hacking with Fire event page and we’ll put that in the queue for the Hack Chat discussion.

join-hack-chat

Our Hack Chats are live community events on the Hackaday.io Hack Chat group messaging. This week is just like any other, and we’ll be gathering ’round our video terminals at noon, Pacific, on Friday, September 14th. That’s not the same in every time zone, but don’t worry, we have some amazing time conversion technology.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io.

You don’t have to wait until Friday; join whenever you want and you can see what the community is talking about.

Fail of the Week: Solid State Relay Fails Spectacularly

A lot of times these days, it seems like we hackers are a little like kids in a candy store. With so many cool devices available for pennies at the click of a mouse, it’s temptingly easy to order first and ask questions about quality later. Most of the time that works out just fine, with the main risk of sourcing a dodgy component being a ruined afternoon of hacking when a part fails.

The stakes are much higher when you’re connecting your project to the house mains, though, as [Mattias Wandel] recently learned when the solid-state relay controlling his water heater failed, with nearly tragic results. With aplomb that defies the fact that he just discovered that he nearly burned his house down, [Mattias] tours the scene of the crime and delivers a postmortem of the victim, a Fotek SSR-25DA. It appears that he mounted it well and gave it a decent heatsink, but the thing immolated itself just the same. The only remnant of the relay’s PCB left intact was the triac mounted to the rear plate. [Mattias] suspects the PCB traces heated up when he returned from vacation and the water heater it was controlling came on; with a tank full of cold water, both elements were needed and enough current was drawn to melt the solder build-up on the high-voltage traces. With the solder gone, the traces cooked off, and the rest is history. It’s a scary scenario that’s worth looking at if you’ve got any SSRs controlling loads anywhere near their rated limit.

The morals of the story: buy quality components and test them if possible; when in doubt, derate; and make sure a flaming component can’t light anything else on fire. And you’ll want to review the basics of fire protection while you’re at it.

Continue reading “Fail of the Week: Solid State Relay Fails Spectacularly”

A Dramatic Demo of AC Versus DC Switching

Switches seem to be the simplest of electrical components – just two pieces of metal that can be positioned to either touch each other or not. As such it would seem that it shouldn’t matter whether a switch is used for AC or DC. While that’s an easy and understandable assumption, it can also be a dangerous one, as this demo of AC and DC switching dramatically reveals.

Using a very simple test setup, consisting of an electric heater for a load, a variac to control the voltage, and a homemade switch, [John Ward] walks us through the details of what happens when those contacts get together. With low-voltage AC, the switch contacts exhibit very little arcing, and even with the voltage cranked up all the way, little more than a brief spark can be seen on either make or break. Then [John] built a simple DC supply with a big rectifier and a couple of capacitors to smooth things out and went through the same tests. Even at a low DC voltage, the arc across the switch contacts was dramatic, particularly upon break. With the voltage cranked up to the full 240-volts of the UK mains, [John]’s switch was essentially a miniature arc welder, with predictable results as the plastic holding the contacts melted. Don your welding helmet and check out the video below.

As dramatic as the demo is, it doesn’t mean we won’t ever be seeing DC in the home. It just means that a little extra engineering is needed to make sure that all the components are up to snuff.

Continue reading “A Dramatic Demo of AC Versus DC Switching”

3D Printer Guardian Watches for Worst-case Failures

Some devices have one job to do, but that job can have many facets. To [jmcservv], an example of this is the job of protecting against worst-case failures in a 3D printer, and it led him to develop the 3D Printer Watchdog Guardian. When it comes to fire, secondary protection is the name of the game because it’s one thing to detect thermal runaway and turn off a heater, but what if that isn’t enough? The MOSFET controlling the heater could have failed closed and can no longer be turned off in a normal sense. In such cases, some kind of backup is needed. Of course, a protection system should also notify an operator of any serious problem, but what’s the best way to do that? These are the kinds of issues that [jmcservv] is working to address with his watchdog, which not only keeps a careful eye on any heating elements in the system, but can take a variety of actions as a result.

Some outcomes (like fire) are bad enough that it’s worth the extra work and cost of additional protection, and that’s the thinking that has led [jmcservv] to submit his watchdog system for The Hackaday Prize.

Friday Hack Chat: Fire and Cars

Summer is here, and it’s time for the question on everyone’s mind: how are they going to get the fuselage of a 747 from the California desert to Burning Man? You can’t put it on a train, and it’s much wider than any truck.

This Friday, we’re not going to be answering the modern-day riddle of the Sphinx, but we are going to the talking about other art cars. For this week’s Hack Chat, we’re going to be discussing dragons made out of school buses and pyrotechnics.

Our guest for this Hack Chat will be [Kevin Bracken], best known as the founder of International Pillow Fight Day, but now he’s the project lead fo Heavy Meta, Canada’s largest art car and fire-breathing dragon sculpture/stage. Heavy Meta is a 30-foot long mutant vehicle with flame effects and a 15,000 watt sound system. It’s also the 3tress, a 2,000 square foot workshop founded with the purpose of building this gigantic art car, and it’s the Toronto Art Car Community, a group of people tasked with manufacturing gigantic lumbering behemoths.

Kevin will be discussing how the Heavy Meta crew transformed a GMC school bus into a dragon, how the team learned to build flame effects, how the pneumatics work, and what it’s like to be on tour with half a dozen Maker Faires.

During this Hack Chat, we’ll be talking about:

  • What an art car is
  • How do you make the electronics
  • What precautions do you take to keep it working on the road
  • How do you control flame effects
  • What are the legal and regulatory considerations of art cars

You are, of course, encouraged to add your own questions to the discussion. You can do that by leaving a comment on the Hack Chat Event Page and we’ll put that in the queue for the Hack Chat discussion.join-hack-chat

Our Hack Chats are live community events on the Hackaday.io Hack Chat group messaging. This week is just like any other, and we’ll be gathering ’round our video terminals at noon, Pacific, on Friday, July 6th.  Here’s a clock counting down the time until the Hack Chat starts.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io.

You don’t have to wait until Friday; join whenever you want and you can see what the community is talking about.

Émilie du Châtelet: An Energetic Life

Émilie du Châtelet lived a wild, wild life. She was a brilliant polymath who made important contributions to the Enlightenment, including adding a mathematical statement of conservation of energy into her French translation of Newton’s Principia, debunking the phlogiston theory of fire, and suggesting that what we would call infrared light carried heat.

She had good company; she was Voltaire’s lover and companion for fifteen years, and she built a private research institution out of a château with him before falling in love with a younger poet. She was tutored in math by Maupertuis and corresponded with Bernoulli and Euler. She was an avid gambler and handy with a sword. She died early, at 41 years, but those years that she did live were pretty amazing. Continue reading “Émilie du Châtelet: An Energetic Life”

Fire. Vortex. Cannon. Need We Say More?

Tornadoes are a rightfully feared natural disaster. Fire tornadoes are an especially odious event to contend with — on top of whatever else is burning. But, a fire vortex cannon? That’s some awesome eye candy.

The madman behind this cannon belching huge gouts of fire is none other than Youtuber [JAIRUS OF ALL]. This build is actually an upgrade to one of his previous projects — a fire tornado gun that burned itself out and is now twice-revived — and is arguably better at creating a proper vortex to direct the flames. Built around a modified NERF gun, a pair of 60mm electric ducted fans with some additional venting — and tunable via a speed controller — direct the airflow through slits in a vortex chamber. A backpack of liquid propane literally fuels this phoenix of a flamethrower, so [JAIRUS] had plenty of time to put together some great footage. Check it out!

Continue reading “Fire. Vortex. Cannon. Need We Say More?”