Hackaday Podcast 071: Measuring Micrometers, The Goldilocks Fit, Little Linear Motors, And 8-bit Games On ESP32

Hackaday editors Mike Szczys and Elliot Williams fan through a fantastic week of hacking. Most laser cutters try to go bigger, but there’s a minuscule one that shows off a raft of exotic components you’ll want in your bag of tricks. Speaking of tricks, this CNC scroll saw has kinematics the likes of which we’ve never seen before — worth a look just for the dance of polar v. Cartesian elements. We’ve been abusing printf() for decades, but it’s possible to run arbitrary operations just by calling this Turing-complete function. We wrap the week up with odes to low-cost laptops and precision measuring.

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (60 MB or so.)

Continue reading “Hackaday Podcast 071: Measuring Micrometers, The Goldilocks Fit, Little Linear Motors, And 8-bit Games On ESP32”

Retrotechtacular: Wire Splicing The Army Way

For those of us who started experimenting with electricity when we were very young, one of the essential first skills was learning how to twist wires together. It seems like there’s not much to learn, but after a few failed attempts with nothing but your fingers, you learned a few tricks that are probably still with you to this day. It’s not surprising, then, that there’s an official US Army way to twist wires together, as this Signal Corps training film from 1941 shows.

Considering that the Signal Corps had nearly 80 years of experience with wiring battlefield communications at the outbreak of World War II, their methods were pretty solid, as were their materials. The film mainly concerns the splicing together of rolls of type W110-B field wire, used by the Signal Corps to connect command posts to forward positions, observation posts, and the rear echelons. More often than not laid directly upon the ground, the wire had to be tough, waterproof, and conductive enough that field telephone gear would still work over long loop lengths. As such, the steel-reinforced, rubber-and-fabric clad cable was not the easiest stuff to splice. Where we might cringe at the stresses introduced by literally tying a conductor in knots, it was all part of the job for the wire-laying teams that did the job as quickly as possible, often while taking enemy fire.

The film also has a section on splicing a new line into an existing, in-service circuit, using a T-splice and paying careful attention to the topology of the knots used, lest they come undone under stress. It’s fascinating how much thought was put into something as mundane as twisting wires, but given the stakes, we can appreciate the attention to detail.

Continue reading “Retrotechtacular: Wire Splicing The Army Way”

A Beginner’s Guide To Lithium Rechargeable Batteries

Batteries were once heavy, awkward things, delivering only a limp amount of current for their size and weight. Thankfully, over time, technology has improved, and in 2020, we’re blessed with capable, high-power lithium polymer batteries that can provide all the power your mobile project could possibly need. There are some considerations one must make in their use however, so read on for a primer on how to properly use LiPos in your project!

So Many Types!

With the first commercial lithium-ion battery entering the market in 1991, the (nearly) 30 years since have seen rapid development. This has led to a proliferation of different technologies and types of battery, depending on construction and materials used. In order to treat your batteries properly, it’s important to know what you’ve got, so paying attention to this is critical. Continue reading “A Beginner’s Guide To Lithium Rechargeable Batteries”

Surviving The Pandemic As A Hacker: Making A Mask Of Your Very Own

As the COVID-19 pandemic has continued along its way through the world, our community has responded as it always does, by designing and making things intended to solve the problems thrown up by the situation we find ourselves in. Much of this effort has gone into the production of PPE to plug the gap and many essential staff have been protected by maker-provided equipment, while the remainder of the effort has produced a wide array of clever designs for COVID-related items.

With curves flattened in many areas, Governments around the world are now encouraging the wearing of face masks in everyday social interactions. The purpose of mask for the general public is for droplet catching rather than virus filtering, and home made masks easily accomplish this. So let’s take a look at what you need to know about making a mast of your very own.

Continue reading “Surviving The Pandemic As A Hacker: Making A Mask Of Your Very Own”

The Hackaday Prize: Field Ready Is Changing The Face Of Humanitarian Relief

It’s one of the enduring images of a humanitarian aid mobilization: military transport planes lined up on runways, ready to receive pallets of every conceivable supply. The cardboard boxes on those shrink-wrapped pallets are filled with everything from baby formula to drinking water, and will join crates filled with the tools and materials needed to shelter, clothe, feed, and heal people in places where civilization has suddenly come into short supply thanks to a disaster, sometimes natural, but often man-made.

What if it didn’t need to be that way? What if, instead of flight after flight of supplies sent in to help rebuild, perhaps just one flight was needed, one stuffed with the tools of our trade: 3D-printers, Arduinos, electronic components, machine tools, and the experts to use them. It certainly wouldn’t make up for the short-term need for food and water, but importing the ability to manufacture the items needed locally would go a long way to repairing infrastructure in the disaster area.

Rethinking disaster response is the core mission of Field Ready, one of the groups we’ve partnered with for the 2020 Hackaday Prize. By way of introduction to this non-profit with a potentially world-changing mission, and to help those who are participating in the 2020 Hackaday Prize challenges, here’s a little bit about Field Ready — what they do, how they see digital manufacturing fitting into their mission, and where they’re going in the future.

Continue reading “The Hackaday Prize: Field Ready Is Changing The Face Of Humanitarian Relief”

Teardown: The Writer Word Processor

For modern students, the spiral notebook has given way to the laptop and the pocket calculator has been supplanted by the smart phone. We’re not just talking about high school and college, either. Today, the education of even grade school children is intrinsically linked with technology. While some might question the wisdom of moving away from the pencil and pad at such a young age, there’s little question that all the kids stuck at home right now due to COVID-19 would have had a much harder time transitioning to remote learning otherwise.

But that certainly wasn’t the case when Advanced Keyboard Technologies released the Writer in 2003. Back then, five years before the first netbooks hit the market, you’d be hard pressed to find a laptop cheap enough to give to a grade school student. In comparison, these small electronic word processors could be purchased for as little as $150. Not only was the initial price low, but the maintenance costs were almost negligible. They ran for hundreds of hours on a standard AA batteries, and didn’t require schools to have any IT staff to manage them. Sure they couldn’t get on the Internet or even run any software, but they would give students a chance to hone their keyboarding skills. Continue reading “Teardown: The Writer Word Processor”

Vernier Calipers And Micrometer Screw Gauges, Measuring Without Compromise

I needed a temperature controller module recently, so off I went to Banggood to order one. As one does I found myself browsing, one thing led to another, and I bought a micrometer screw gauge. While micrometers are pretty expensive devices, reflecting their high precision engineering and construction, this micrometer cost me only about £8, or just under $10, definitely in the spirit of our long-running series of reviewing very cheap tools in search of a diamond in the rough. But perhaps more importantly, this is also the cue for an examination of high precision dimensional measurement. So I’ve assembled a collection of micrometers and vernier calipers of varying quality, and it’s time to dive in and measure some very small things.

Some of you will be metrology enthusiasts with an array of the finest devices available, but I am guessing that many of you will not. The ubiquitous precision measurement device in our community appears to be the digital caliper, a sliding clamp with an LCD display, an instrument that can be had in its most basic form for a very small outlay indeed. For the purposes of this piece though we’re not looking at digital devices but their analogue precursors. If you want a feel for metrology and you’d like some of those heritage tools that parents pass onto their kids then it’s time to learn something about the vernier caliper and the micrometer. Continue reading “Vernier Calipers And Micrometer Screw Gauges, Measuring Without Compromise”