An Over-Engineered Basement Monitor

[Stephen] has a basement that depends on a sump pump. What that means is if the pump fails or the power goes out, the basement floods—which is rather undesirable. Not wanting to rely on a single point of failure, [Stephen] decided to build a monitor for the basement situation, which quickly spiralled to a greater degree of complexity than he initially expected.

The initial plan was just to have water level sensors reporting data over a modified CATS packet radio transmitter. On the other end, the plan was to capture the feed via a CATS receiver, pipe the data to the internet via FELINET, and then have the data displayed on a Grafana dashboard. Simple enough. From there, though, [Stephen] started musing on the possibilities. He thought about capturing humidity data to verify the dehumidifier was working. Plus, temperature would be handy to get early warning before any pipes were frozen in colder times. Achieving those aims would be easy enough with a BME280 sensor, though hacking it into the CATS rig was a little challenging.

The results are pretty neat, though. [Stephen] can now track all the vital signs of his basement remotely, with all the data displayed elegantly on a nice Grafana dashboard. If you’re looking to get started on a similar project, we’ve featured a great Grafana guide at a previous Supercon, just by the by. All in all, [Stephen’s] project may have a touch of the old overkill, but sometimes, the most rewarding projects are the ones you pour your heart and soul into!

E-Ink Screen Combined With Analog Dial Is Epic Win

Analog dials used to be a pretty common way of displaying information on test equipment and in industrial applications. They fell out of favor as more advanced display technologies became cheaper. However, if you combine an analog dial with a modern e-ink display, it turns out you get something truly fantastic indeed.

This build comes to us from [Arne]. The concept is simple—get an e-ink display, and draw a dial on it using whatever graphics and scale you choose. Then, put it behind a traditional coil-driven analog dial in place of the more traditional paper scale. Now, you have an analog dial that can display any quantity you desire. Just update the screen to display a different scale as needed. Meanwhile, if you don’t need to change the display, the e-ink display will draw zero power and still display the same thing.

[Arne] explains how it all works in the writeup. It’s basically a LilyGo T5 ESP32 board with an e-ink screen attached, and it’s combined with a MF-110A multimeter. It’s super easy to buy that stuff and start tinkering with the concept yourself. [Arne] uses it with Home Assistant, which is as good an idea as any.

You get all the benefits of a redrawable display, with the wonderful visual tactility of a real analog dial. It’s a build that smashes old and new together in the best way possible. It doesn’t heart that [Arne] chose a great retro font for the dial, either. Applause all around!

3D Printed Boat Uses Tank Tracks For Amphibious Propulsion

Boats normally get around with propellers or water jets for propulsion. Occasionally, they use paddles. [Engineering After Hours] claims he is “changing the boat game forever” with his new 3D printed boat design that uses a tank tread for propulsion instead. Forgive him for the hyperbole of the YouTuber. It’s basically a modified paddle design, but it’s also pretty cool.

It works on land, even if it doesn’t steer well!

The basic idea is simple enough—think “floating snowmobile” and you’re in the ballpark. In the water, the chunky tank track provides forward propulsion with its paddle-like treads. It’s not that much different from a paddle wheel steamer. However, where it diverges is that it’s more flexible than a traditional paddle wheel.

The tracked design is actually pretty good at propelling the boat in shallow water without getting stuck. In fact, it works pretty well on dirt, too! The video covers the basic concept, but it also goes into some detail regarding optimizing the design, too. Getting the float and track geometry right is key to performance, after all.

If you’re looking to build an oddball amphibious craft, maybe working with the snowmobile concept is worth your engineering time. Continue reading “3D Printed Boat Uses Tank Tracks For Amphibious Propulsion”

Drilling Rig Makes Accurate Holes In Seconds

Drilling holes can be quite time consuming work, particularly if you have to drill a lot of them. Think about all the hassle of grabbing a part, fixturing it in the drill press, lining it up, double checking, and then finally making the hole. That takes some time, and that’s no good if you’ve got lots of parts to drill. There’s an easy way around that, though. Build yourself a rad jig like [izzy swan] did.

The first jig we get to see is simple. It has a wooden platter, which hosts a fixture for a plastic enclosure to slot perfectly into place. Also on the platter is a regular old power drill. The platter also has a crank handle which, when pulled, pivots the platter, runs the power drill, and forces it through the enclosure in the exact right spot. It’s makes drilling a hole in the enclosure a repeatable operation that takes just a couple of seconds. The jig gets it right every time.

The video gets better from there, though. We get to see even niftier jigs that feature multiple drills, all doing their thing in concert with just one pull of a lever. [izzy] then shows us how these jigs are built from the ground up. It’s compelling stuff.

If you’re doing any sort of DIY manufacturing in real numbers, you’ve probably had to drill a lot of holes before. Jig making skills could really help you if that’s the case. Video after the break.

Continue reading “Drilling Rig Makes Accurate Holes In Seconds”

Build Yourself A Useful Resistor Decade Box

If you’ve ever worked with guitar pedals or analog audio gear, you’ve probably realized the value of a resistor decade box. They substitute for a resistor in a circuit and let you quickly flick through a few different values at the twist of a knob. You can still buy them if you know where to look, but [M Caldeira] decided to build his own.

At its core, the decade box relies on a number of 11-position rotary switches. Seven are used in this case—covering each “decade” of resistances, from 1 ohm to 10 ohm and all the way up to 1 megaohm. The 11 positions on each switch allows the selection of a given resistance. For example, position 7 on the 100 ohm switch selects 700 ohms, and adds it to the total resistance of the box.

[M Caldeira] did a good job of building the basic circuit, as well as assembling it in an attractive, easy-to-use way. It should serve him well on his future audio projects and many others besides. It’s a simple thing, but sometimes there’s nothing more satisfying than building your own tools.

We’ve seen other neat designs like this in the past, including an SMD version and this neat digital decade box. Video after the break.

Continue reading “Build Yourself A Useful Resistor Decade Box”

Enhiker Helps You Decide If Its A Good Day To Hike

Many of us check the weather before heading out for the day — we want to know if we’re dressed (or equipped) properly to handle what Mother Nature has planned for us. This is even more important if you’re going out hiking, because you’re going to be out in a more rugged environment. To aid in this regard, [Mukesh Sankhla] built a tool called Enhiker.

The concept is simple; it’s intended to tell you everything you need to know about current and pending conditions before heading out on a hike. It’s based around Unihiker, a single-board computer which also conveniently features a 2.8-inch touch screen. It’s a quad-core ARM device that runs Debian and has WiFi and Bluetooth built in, too. The device is able to query its GPS/GNSS receiver for location information, and then uses this to get accurate weather data online from OpenWeatherMap. It makes some basic analysis, too. For example, it can tell you if it’s a good time to go out, or if there’s a storm likely rolling in, or if the conditions are hot enough to make heat stroke a concern.

It’s a nifty little gadget, and it’s neat to have all the relevant information displayed on one compact device. We’d love to see it upgraded further with cellular connectivity in addition to WiFi; this would make it more capable when out and about.

We’ve seen some other neat hiking hacks before, too, like this antenna built with a hiking pole. Meanwhile, if you’ve got your own neat hacks for when you’re out on the trail, don’t hesitate to let us know!

Learn About Robot Arms By Building Pedro 2.0

Whether you’re a kid or a kid at heart, learning about science and engineering can be a lot more fun if it’s practical. You could sit around learning about motors and control theory, or you could build a robot arm and play with it. If the latter sounds like your bag of hammers, you might like Pedro 2.0.

Pedro 2.0 is a simple 3D-printable robot arm intended for STEAM education. If you’re new to that acronym, it basically refers to the combination of artistic skills with education around science, technology, engineering and mathematics.

The build relies on components that are readily available pretty much around the world—SG90 servo motors, ball bearings, and an Arduino running the show. There’s also an NRF24L01 module for wireless remote control. All the rest of the major mechanical parts can be whipped up on a 3D printer, and you don’t need a particularly special one, either. Any old FDM machine should do the job just fine if it’s calibrated properly.

If you fancy dipping your toes in the world of robot arms, this is a really easy starting point that will teach you a lot along the way. From there, you can delve into more advanced designs, or even consider constructing your own tentacles. The world really is your octopus oyster.