Author: Dan Maloney

3359 Articles

Get Into Meshtastic On The Cheap With This Tiny Node Kit

March 8, 2025 by 16 Comments

There’s been a lot of buzz about Meshtastic lately, and with good reason. The low-power LoRa-based network has a ton of interesting use cases, and as with any mesh network, the more nodes there are, the better it works for everyone. That’s why we’re excited by this super-affordable Meshtastic kit that lets you get a node on the air for about ten bucks.

The diminutive kit, which consists of a microcontroller and a LoRa module, has actually been available from the usual outlets for a while. But [concretedog] has been deep in the Meshtastic weeds lately, and decided to review its pros and cons. Setup starts with flashing Meshtastic to the XIAO ESP32-S3 microcontroller and connecting the included BLE antenna. After that, the Wio-SX1262 LoRa module is snapped to the microcontroller board via surface-mount connectors, and a separate LoRa antenna is connected. Flash the firmware (this combo is supported by the official web flasher), and you’re good to go.

What do you do with your new node? That’s largely up to you, of course. Most Meshtastic users seem content to send encrypted text messages back and forth, but as our own [Jonathan Bennett] notes, a Meshtastic network could be extremely useful for emergency preparedness. Build a few of these nodes, slap them in a 3D printed box, distribute them to willing neighbors, and suddenly you’ve got a way to keep connected in an emergency, no license required.

Trio Of Mods Makes Delta Printer More Responsive, Easier To Use

March 7, 2025 by 9 Comments

Just about any 3D printer can be satisfying to watch as it works, but delta-style printers are especially hypnotic. There’s just something about the way that three linear motions add up to all kinds of complex shapes; it’s mesmerizing. Deltas aren’t without their problems, though, which led [Bruno Schwander] to undertake a trio of interesting mods on his Anycubic Kossel.

First up was an effort to reduce the mass of the business end of the printer, which can help positional accuracy and repeatability. This started with replacing the stock hot-end with a smaller, lighter MQ Mozzie, but that led to cooling problems that [Bruno] addressed with a ridiculously overpowered brushless hairdryer fan. The fan expects a 0 to 5-VDC signal for the BLDC controller, which meant he had to build an adapter to allow Marlin’s 12-volt PWM signal to control the fan.

Once the beast of a fan was tamed, [Bruno] came up with a clever remote mount for it. A 3D-printed shroud allowed him to mount the fan and adapter to the frame of the printer, with a flexible duct connecting it to the hot-end. The duct is made from lightweight nylon fabric with elastic material sewn into it to keep it from taut as the printhead moves around, looking a bit like an elephant’s trunk.

Finally, to solve his pet peeve of setting up and using the stock Z-probe, [Bruno] turned the entire print bed into a strain-gauge sensor. This took some doing, which the blog post details nicely, but it required building a composite spacer ring for the glass print bed to mount twelve strain gauges that are read by the venerable HX711 amplifier and an Arduino, which sends a signal to Marlin when the head touches the bed. The video below shows it and the remote fan in action.

Continue reading “Trio Of Mods Makes Delta Printer More Responsive, Easier To Use” →

Hacking Digital Calipers For Automated Measurements And Sorta-Micron Accuracy

March 6, 2025 by 14 Comments

We’ll take a guess that most readers have a set of digital calipers somewhere close to hand right now. The cheapest ones tend to be a little unsatisfying in the hand, a bit crusty and crunchy to use. But as [Matthias Wandel] shows us, these budget tools are quite hackable and a lot more precise than they appear to be.

[Matthias] is perhaps best known around these parts for making machine tools using mainly wood. It’s an unconventional material for things like the CNC router he loves to hate, but he makes it work through a combination of clever engineering and a willingness to work within the limits of the machine. To assess those limits, he connected some cheap digital calipers to a Raspberry Pi by hacking the serial interface that seems to be built into all of these tools. His particular calipers output a pair of 24-bit words over a synchronous serial connection a couple of times per second, but at a level too low to be read by the Pi. He solved this with a clever resistor ladder to shift the signals to straddle the 1.8 volt transition on the Pi, and after solving some noise problems with a few strategically placed capacitors and some software debouncing, he was gathering data on his Pi.

Although his setup was fine for the measurements he needed to make, [Matthias] couldn’t help falling down the rabbit hole of trying to milk better resolution from the calipers. On paper, the 24-bit output should provide micron-ish resolution, but sadly, the readings seem to fluctuate rapidly between two levels, making it difficult to obtain an average quickly enough to be useful. Still, it’s a good exercise, and overall, these hacks should prove handy for anyone who wants to dip a toe into automated metrology on a budget.

Continue reading “Hacking Digital Calipers For Automated Measurements And Sorta-Micron Accuracy” →

Piggyback Board Brings Touch Sensing To USB Soldering Iron

March 5, 2025 by 20 Comments

The current generation of USB-powered soldering irons have a lot going for them, chief among them being portability and automatic start and stop. But an iron that turns off in the middle of soldering a joint is a problem, one that this capacitive-touch replacement control module aims to fix.

The iron in question is an SJ1 from Awgem, which [DoganM95] picked up on Ali Express. It seems well-built, with a sturdy aluminum handle, a nice OLED display, and fast heat-up and cool-down. The problem is that the iron is triggered by motion, so if you leave it still for more than a second or two, such as when you’re soldering a big joint, it turns itself off. To fix that,[DoganM95] designed a piggyback board for the OEM controller with a TTP223 capacitive touch sensor. The board is carefully shaped to allow clearance for the existing PCB components and the heater cartridge terminals, and has castellated connections so it can connect to pads on the main board. You have to remove one MOSFET from the main board, but that’s about it for modifications. A nickel strip makes contact with the inside of the iron’s shell, turning it into the sensor plate for the TTP223.

[DoganM95] says that the BA6 variant of the chip is the one you want, as others have a 10-second timeout, which would defeat the purpose of the mod. It’s a very nice bit of design work, and we especially like how the mod board nests so nicely onto the OEM controller. It reminds us a little of those Quansheng handy-talkie all-band mods.

Big Chemistry: Glass

March 5, 2025 by 12 Comments

Humans have been chemically modifying their world for far longer than you might think. Long before they had the slightest idea of what was happening chemically, they were turning clay into bricks, making cement from limestone, and figuring out how to mix metals in just the right proportions to make useful new alloys like bronze. The chemical principles behind all this could wait; there was a world to build, after all.

Among these early feats of chemical happenstance was the discovery that glass could be made from simple sand. The earliest glass, likely accidentally created by a big fire on a sandy surface, probably wasn’t good for much besides decorations. It wouldn’t have taken long to realize that this stuff was fantastically useful, both as a building material and a tool, and that a pinch of this and a little of that could greatly affect its properties. The chemistry of glass has been finely tuned since those early experiments, and the process has been scaled up to incredible proportions, enough to make glass production one of the largest chemical industries in the world today.

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CNC Router And Fiber Laser Bring The Best Of Both Worlds To PCB Prototyping

March 4, 2025 by 22 Comments

Jack of all trades, master of none, as the saying goes, and that’s especially true for PCB prototyping tools. Sure, it’s possible to use a CNC router to mill out a PCB, and ditto for a fiber laser. But neither tool is perfect; the router creates a lot of dust and the fiberglass eats a lot of tools, while a laser is great for burning away copper but takes a long time to burn through all the substrate. So, why not put both tools to work?

Of course, this assumes you’re lucky enough to have both tools available, as [Mikey Sklar] does. He doesn’t call out which specific CNC router he has, but any desktop machine should probably do since all it’s doing is drilling any needed through-holes and hogging out the outline of the board, leaving bridges to keep the blanks connected, of course.

Once the milling operations are done, [Mikey] switches to his xTool F1 20W fiber laser. The blanks are placed on the laser’s bed, the CNC-drilled through holes are used as fiducials to align everything, and the laser gets busy. For the smallish boards [Mikey] used to demonstrate his method, it only took 90 seconds to cut the traces. He also used the laser to cut a solder paste stencil from thin brass shim stock in only a few minutes. The brief video below shows the whole process and the excellent results.

In a world where professionally made PCBs are just a few mouse clicks (and a week’s shipping) away, rolling your own boards seems to make little sense. But for the truly impatient, adding the machines to quickly and easily make your own PCBs just might be worth the cost. One thing’s for sure, though — the more we see what the current generation of desktop fiber lasers can accomplish, the more we feel like skipping a couple of mortgage payments to afford one.

Continue reading “CNC Router And Fiber Laser Bring The Best Of Both Worlds To PCB Prototyping” →

Deep Space DX Hack Chat

March 3, 2025 by 5 Comments

Join us on Wednesday, March 5 at noon Pacific for the Deep Space DX Hack Chat with David Prutchi!

In the past 70-odd years, the world’s space-faring nations have flung a considerable amount of hardware out into the Void. Most of it has fallen back into Earth’s gravity well, and a lot of what remains is long past its best-by date, systems silenced by time and the harsh conditions that rendered these jewels of engineering into little more than space flotsam.

Luckily, though, there are still a few spacecraft plying the lonely spaces between the planets and even beyond that still have active radios, and while their signals may be faint, we can still hear them. True, many of them are reachable only using immense dish antennas.

join-hack-chatNot every deep-space probe needs the resources of a nation-state to be snooped on, though. David Prutchi has been listening to them for years using a relatively modest backyard antenna farm and a lot of hard-won experience. He’s been able to bag some serious DX, everything from rovers on Mars to probes orbiting Jupiter. If you’ve ever wanted to give deep space DX a try, here’s your chance to get off on the right foot.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, March 5 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.