You may have heard of a heart of glass or have a glass jaw, but have you ever seen a glass robot?
[Simone Giertz], has taken two of her favorite things, stained glass and robotics, and fused them into a single project. Using an existing metal robot arm as a template, she cut and soldered her stained glass panels before reassembling the robot with its new solarpunk limbs. During testing though, one of the glass panels repeatedly failed at a solder joint.
Undaunted, [Giertz] replaced the faulty piece with an original metal component allowing this “grandma cyberpunk-core” bot to prepare tea as intended. We really love when makers bring us through the whole process, mishaps and all, and [Giertz] never disappoints in this respect. We do wonder a bit about the long-term health impacts of making tea with a robot containing leaded solder though.
If you’re interested in more robots made from unusual materials, checkout this gripper made from a dead spider or this work on phase changing robots.
Continue reading “Glass Robot From A Solarpunk Future”
While there are plenty of places around the world to get a great cup of tea, no one has quite burned it into their culture like those in the United Kingdom. While they don’t have the climate to grow the plants themselves, they at least have figured out the art of heating water extremely rapidly in purpose-built electric kettles while the rest of us wait to heat water on our stoves and microwaves. But that’s still not fast enough for some, like [Finlay Shellard], who just completed this jet-powered tea kettle.
[Finlay] took some inspiration cues and parts from another jet engine he had on hand that was powering his toaster. This is a pulse jet design, which is welded together from laser-cut pieces of sheet metal with guides welded in place to allow water to flow around the combustion chamber and exhaust. Pressurized water sits in a reservoir at the top of the engine, and when it is up to temperature, a valve allows it to flow to the engine to heat up. When it has passed the jet engine section, it passes a tea bag holder and then out of a spout at the end of the engine.
A few tests at 100 PSI had the hot tea exiting the engine in a non-linear fashion, so the pressure was reduced. The device now makes tea at incredibly fast speeds, with the only downsides being access to some sort of jet fuel, and also the need for a protective hearing device of some sort. For anyone attempting to do this themselves, take a look at this build which includes a turbocharger design for improved efficiency of the pulse jet itself.
Continue reading “Jet Engine Powers Tea Kettle”
When it comes to high-speed, high-voltage switching, there are a wealth of components to choose from — MOSFETS, thyristors, IGBTs, and even vacuum tubes like thyratrons. But who needs all that expensive silicon (or glass) when all you need to build a high-voltage switch is some plumbing fixtures and a lathe?
At least that’s the approach that budget-minded laser experimenter [Les Wright] took with his latest triggered spark gap build. We’ve been watching his work for a while now, especially his transversely excited atmospheric (TEA) lasers. These are conceptually simple lasers that seem easy to build, at least compared to other lasers. But they do require a rapid pulse of high voltage across their long parallel electrodes to lase, and controlling the pulse is where this triggered spark gap shines.
The spark gap is made from brass plumbing fittings on either end of a short PVC coupler. [Les] used his lathe to put a thread into one of the caps to accept a spark plug, the center electrode of which pokes through a small hole in the metal cathode. To trigger the spark gap, [Les] built a trigger generator that outputs about 15,000 volts, which arcs from the spark plug electrode to the spark gap cathode in the low-pressure nitrogen environment. Little spark leads to big spark, big spark discharges a capacitor across the laser electrodes, and you’ve got a controlled single-shot laser. Check it out in the video below.
Honestly, the more we see of [Les]’ videos, the more we want to play with lasers and high voltage. From DIY doorknob caps to blasting Bayer arrays off cheap CCD cameras, there’s always something fun — and slightly dangerous — going on in [Les]’s lab.
Continue reading “Spark Plug And Plumbing Parts Bring Nitrogen Laser Under Control”
How far would you go for your cup of tea? [samsungite]’s missus doesn’t like clutter on her countertops, so away the one-cup kettle would go back into the cupboard for next time while the tea steeped. As long as there’s room for it in there, why not install it there permanently? That’s the idea behind RoboTray, which would only be cooler if it could be plumbed somehow.
RoboTray went through a few iterations, most importantly the switch from 6mm MDF to 4 mm aluminum plate. A transformer acts as a current sensor, and when the kettle is powered on, the tray first advances forward 7 cm using a 12 VDC motor and an Arduino. Then it pivots 90° on a lazy Susan driven by another 12 VDC motor. The kettle is smart enough to turn itself off when finished, and the Arduino senses this and reverses all the steps after a ten-second warning period. Check it out in action after the break.
If [samsungite] has any more Arduinos lying around, he might appreciate this tea inventory tracker.
Continue reading “RoboTray Is A Secret Tea Butler”
Mouser and Digi-Key are great for servicing most needs, and the range of parts they offer is frankly bewildering. But given the breadth of the hardware hacking community’s interests, few companies could afford to be the answer to everyone’s needs.
That’s especially true for the esoteric parts needed when one’s hobby involves high voltages and homemade lasers, like [Les Wright]. He recently came up with a DIY doorknob capacitor design that makes the hard-to-source high-voltage caps much easier to obtain. We’ve seen [Les] use these caps in his transversely excited atmospheric (TEA) lasers, a simple design that uses high-voltage discharge across a long, narrow channel filled with either room air or nitrogen. The big ceramic caps are needed for the HV supply, and while [Les] has a bunch, they’re hard to come by online. He tried a follow-up using plain radial-lead ceramic capacitors, and while the laser worked, he did get some flashover between the capacitor leads.
[Les]’s solution was to dunk the chunky caps in acetone for a week or so to remove their epoxy covering. Once denuded, the leads were bent into a more axial configuration and soldered to brass machine screws. The dielectric slug is then put in a small section of plastic tubing and potted in epoxy resin with the bolts protruding from each end. The result is hard to distinguish from a genuine doorknob cap; the video below shows the build process as well as some testing.
Hats off to [Les] for taking pity on those of us who want to replicate his work but find ourselves without these essentials. It’s nice to know there’s a way to make unobtanium parts when you need them.
Continue reading “Homebrew Doorknob Caps For High-Voltage Fun”
Sometimes the decision to tackle a project or not can boil down to sourcing parts. Not everything is as close as a Digi-Key or Mouser order, and relying on the availability of surplus parts from eBay or other such markets can be difficult. Knowing if and when a substitute will work for an exotic part can sometimes be a project all on its own.
Building lasers is a great example of this, and [Les Wright] recently looked at substitutes for hard-to-find “doorknob” capacitors for his transversely excited atmospheric lasers. We took at his homebrew TEA lasers recently, which rely on a high voltage supply and very rapid switching to get nitrogen gas to lase. His design uses surplus doorknob caps, big chunky parts rated for very high voltages but also with very low parasitic inductance, which makes them perfect for the triggering circuit.
[Les] tried to substitute cheaper and easier-to-find ceramic power caps with radial wire leads rather than threaded lugs. With a nominal 40-kV rating, one would expect these chunky blue caps to tolerate the 17-kV power supply, but as he suspected, the distance between the leads was short enough to result in flashover arcing. Turning down the pressure in the spark gap chamber helped reduce the flashover and prove that these caps won’t spoil the carefully engineered inductive properties of the trigger. Check out the video below for more details.
Thanks to [Les] for following up on this and making sure everyone can replicate his designs. That’s one of the things we love about this community — true hackers always try to find a way around problems, even when it’s just finding alternates for unobtanium parts.
Continue reading “No Doorknobs Needed For This Nitrogen Laser Build”
If lasers are your hobby, you face a conundrum. There are so many off-the-shelf lasers that use so many different ways of amplifying and stimulating light that the whole thing can be downright — unstimulating. Keeping things fresh therefore requires rolling your own lasers, and these DIY nitrogen TEA and dye lasers seem like a fun way to go.
These devices are the work of [Les Wright], who takes us on a somewhat lengthy but really informative tour of transversely excited atmospheric (TEA) lasers. The idea with TEA lasers is that a gas, often carbon dioxide in commercial lasers but either air or pure nitrogen in this case, is excited by a high-voltage discharge across long parallel electrodes. TEA lasers are dead easy to make — we’ve covered them a few times — but as [Les] points out, that ease of construction leads to designs that are more ad hoc than engineered.
In the video below, [Les] presents three designs that are far more robust than the typical TEA laser. His lasers use capacitors made from aluminum foil with polyethylene sheets for dielectric, sometimes with the addition of beautiful “doorknob” ceramic caps too. A spark gap serves as a very fast switch to discharge high voltage across the laser channel, formed by two closely spaced aluminum hex bars. Both the spark gap and the laser channel can be filled with low-pressure nitrogen. [Les] demonstrates the power and the speed of his lasers, which can even excite laser emissions in a plain cuvette of rhodamine dye — no mirrors needed! Although eye protection is, of course.
These TEA lasers honestly look like a ton of fun to build and play with. You might not be laser welding or levitating stuff with them, but that’s hardly the point.
Continue reading “How About A Nice Cuppa TEA Laser?”