Chess is a slow game of careful decision-making, looking several moves ahead of the current state of the board. So is machining, and combining the two is an excellent way to level up your machine shop chops. And so we have the current project from [John Creasey] who is machining a chess set out of stainless steel.
This isn’t that new-fangled computer numerical control at work, it’s the time-tested art of manual machining. Like chess, you need to plan several steps ahead to ensure you have a way to mount the part for each progressive machining process. In this first video of the series [John] is milling the knights — four of them, with two which will eventually get a black oxide treatment.
Milling the horse head is fun to watch, but you’ll be delighted when the work gets to the base. [John] is using a pipe fitting as a fixture to hold the already-milled horse-head-end while working the base on his lathe. The process begins by getting rid of the inner threads, then working the pipe fitting very carefully to the diameter of the chess piece for a perfect press fit. Neat!
At the end, [John] mentions it took “quite a few months of weekends to get to this point” of having four pieces made. They look great and we can’t wait to see the next piece in the set come to life. You’ll find the video embedded below, but if you can’t sink this kind of time into your own chess set, you may try three-dimensional laser cut acrylic pieces.
[Niklas Roy] has always wanted to try out thermal imaging and saw his opportunity when he received one of those handheld IR thermometers as a gift. But not content with just pointing it at different spots and looking at the temperatures on the LCD display, he decided to use it as the basis for a scanning, thermal imaging system that would display a heat map of a chosen location on his laptop.
He still wanted to to be able to use the IR thermometer as normal at a later date so cutting it open was not an option. Instead he firmly mounted a webcam to it pointing at the LCD display. He then wrote software on his laptop to process the resulting image and figure out what temperature was being displayed.
Once he got that working, he next put the thermometer on a platform with servos connected to an Arduino for slowly rotating it in the horizontal and vertical directions, also under control of the software on his laptop. Each time the thermometer measures the temperature of a spot, the software decodes the temperature on the LCD display and then tells the Arduino to use the servos to point the thermometer at the next spot to be measured. Each measurement takes a little time, so scanning an entire location as 70×44 spots takes around a half hour. But the end result is a heat map drawn on the laptop, done by a device that is low-tech. [Editor’s Snark: Because attaching a webcam and processing the images is “low-tech” these days.] He can overlay the heat map on a normal photo to see at a glance where the hot spots are.
The software he wrote is available on GitHub and the video below shows it in action. We’ve got to admit, it’s pretty awesome to watch. You can even see the heat map being filled in one measurement at a time.
Recently, [Manuel] did a post on making logic gates out of anything. He mentioned a site about relay logic. While it is true that you can build logic gates using switch logic (that is, two switches in series are an AND gate and two in parallel are an OR gate), it isn’t the only way. If you are wiring a large circuit, there’s some benefit to having regular modules. A lot of computers based on discrete switching elements worked this way: you had a PCB that contained some number of a basic gate (say, a two input NAND gate) and then the logic was all in how you wired them together. And in this context, the SPDT relay was used as a two input multiplexer (or mux).
In case you think the relay should be relegated to the historical curiosity bin, you should know there are still applications where they are the best tool for the job. If you’re not convinced by normal macroscopic relays, there is some work going on to make microscopic relays in ICs. And even if they don’t use relays to do it, some FPGAs use mux-based logic inside. So it’s worth your time to dig into the past and see how simply switching between two connections can make a computer.
How do you go from a two input mux to an arbitrary logic gate? Simple, if you paid attention to the banner image. (Or try it interactive). The mux symbols show the inputs to the left, the output to the right and the select input at the bottom. If the select is zero, the “0” input becomes the output. If the select is one, the “1” input routes to the output.
When we see a new build by [Gord] from Gord’s Garage, we never know what to expect. He seems to be pretty skilled at whatever he puts his hand to, with a great design sense and impeccable craftsmanship. You might expect him to tone it down a little for a STEM-outreach wind turbine project then, but when you get a chance to impress 28 fifth and sixth graders, you might as well go for it.
Starting with an idea from his daughter’s teacher for wind turbines each kid could make, [Gord] applied a little lean methodology so the kids would be able to complete the build in the allotted time. The design is simple – a couple of old CDs holding vertical sections of PVC tubing to catch the breeze and spin neodymium magnets over four flat coils of magnet wire. It’s enough to light a single LED and perhaps a kid’s imagination.
As simple as the turbine is, the process of building it needed to be stripped of as much unnecessary work as possible, and [Gord] really shines here. He built jigs and fixtures galore, pre-built some assemblies, and set up well-organized workstations for each step of the build. Everything was clearly labeled, adult volunteers were trained using the video after the break, and a good time was had by all.
Sometimes the hack isn’t in the product but in the process, and [Gord] managed to hack a success out a potential disaster of disappointed kids. If getting a taste of [Gord]’s style makes you want to see more, check out his guitar fretting jig or his brake rotor mancave clock.
Scenario: your little three-hour boat tour runs into a storm, and you’re shipwrecked on a tropic island paradise. You’re pretty sure your new home was once a nuclear test site, but you have no way to check. Only your scrap bin, camera bag, and hot glue gun survived the wreck. Can you put together a Geiger-Müller counter from scrap and save the day?
Probably not, unless your scrap bin is unusually well stocked and contains a surplus Russian SI-3BG miniature Geiger tube, the heart of [GH]’s desert island build. These tubes need around 400 volts across them for incident beta particles or gamma rays to start the ionization avalanche that lets it produce an output pulse. [GH]’s build uses the flash power supply of a disposable 35mm camera to generate the high voltage needed, but you could try using a CCFL inverter, say. The output of the tube tickles the base of a small signal transistor and makes a click in an earbud for every pulse detected.
You’ll no doubt notice the gallons of hot glue, alligator clips, and electrical tape used in the build, apparently in lieu of soldering. While we doubt the long-term robustness of this technique, far be it from us to cast stones – [GH] shows us what you can accomplish even when you find yourself without the most basic of tools.
KiCad is the premiere open source electronics design automation suite. It’s used by professionals and amateurs alike to design circuits and layout out printed circuit boards. In recent years we’ve seen some incredible features added to KiCad like an improved 3D viewer and push-and-shove routing. This Friday at 10 am PST, join in a Hack Chat with KiCad lead developer [Wayne Stambaugh] to talk about recent improvements and what the team has planned for KiCad in the future.
[Wayne] has been an electronics engineer for over 30 years with a wide range of experience in analog and digital hardware design and embedded and application software design. He started hacking on KiCad ten years ago when the project was first opened to public development and a little over two years ago became the project leader. This is an excellent opportunity to learn how the development team works, what their current goals are, and to talk all things KiCad.
Also on Friday, taking place just an hour before the KiCad chat, is a Tindie Hack Chat. All are welcome as the 9:00 am PST discussion gets under way. Discussion will focus on all aspects of selling unique hardware on Tindie.
Here’s How to Take Part:
Hack Chat are live community events that take place in the Hackaday.io Hack Chat group messaging. Visit that page (make sure you are logged in) and look for the “Join this Project Button” in the upper right. Once you are part of the project, that button will change to “Team Messaging” which takes you to the Hack Chat.
You don’t have to wait for Friday, join Hack Chat whenever you like and see what the community is currently talking about.
Join Us Next Week Too for CircuitPython
Block out your calendar for noon PST on Friday the 27th for next week’s Hack Chat. Joining us are Adafruit’s Ladyada, Tony DiCola, and Scott Shawcoft. They’ll be leading a discussion about CircuitPython Beta, Adafruits new extension to MicroPython that adds SAMD21 support and other enhancements.
In most mechanical systems, metal gears that bend are a bad thing. But not so for strain wave gearing, which is designed to take advantage of a metal gear flexing to achieve an action much like planetary gears. The fun isn’t limited to metal anymore, though, if you 3D print a strain wave gear like this.
Strain-wave gearing is nothing new – it was invented in 1957 and has traveled to the moon on the lunar rover. And you may recall [Kristine Panos]’ recent article on a LEGO strain wave gear, which makes it easy to visualize how they work. She also has a great description of how the flex spline, wave generator, and circular spline interact, so we’ll spare those details here. [Simon Merret]’s interpretation of the strain wave gear is very simple and similar to other 3D-printed versions, except that he uses an inside-out timing belt as the flex spline. The wave generator is just an arm with a roller bearing at each end, and despite needing a few tweaks the gear does an admirable job.
Simon is reaching out for help in getting this gear ready for use where the industrial versions see frequent application – the first and second degrees of freedom of robotic arms. If you’ve got any ideas, head over to his project page on Hackaday.io and pitch in.