Disposable Rocket Stove Keeps You Fueled In The Wild

June 1, 2021 by Kristina Panos 55 Comments

Don’t know about you, but we can’t start the day without coffee and a shower. If you were to drag us on some overnight trip into the wilderness, we could probably forego the shower for a day, but we will be a grumpy trail mate without some kind coffee, even instant.

Yes, if you were to get us on an overnight outdoor adventure, we would insist on bringing along a couple of these little disposable, self-destructing rocket stoves, if for no other reason than that we can have some coffee without having to forage for a bunch of firewood and build a whole regular-sized campfire. Don’t worry — we’ll share the water because there’s plenty of time built in. Per [smogdog], these Swedish torches will boil water in 20 minutes and burn for 60 — that’s enough time to make a coffee, a bowl of soup, and toast a single marshmallow before the fire consumes the scrap wood.

We love the use of bike chain as a burner to raise up the pot for fire ventilation. But our favorite bit has to be the dual-purpose packaging. It’s nice-looking, it’s informative, and it’s paper, so you can use it as a fire starter. Failing that, [smogdog] has a backup fire starter system — rubbing alcohol in a small spray bottle. Unwrap a protein bar and check out the demo video after the break.

Tired of the same old, boring trail foods? How about flat-pack pasta that morphs into fun shapes when you boil it?

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Tiny DeLorean Made From Lighters Is A Total Gas

May 18, 2021 by Kristina Panos 29 Comments

There’s making stuff out of trash, and then there’s mind-blowing stuff like this: a DeLorean built from four disposable cigarette lighters and various other bits and bobs like wire sheathing and cotton bud sticks. If it weren’t for the video evidence embedded below, we would have never believed that [Ank Creative] or anyone else could have turned boxy acrylic into the fastback time machine we all know and love.

Is the back window the most important detail? Maybe.

[Ank Creative] seems to have wasted no parts of the lighters, and even saved themselves a bit of trouble by using curved scraps to make the wheel wells. After installing the windshield, we certainly didn’t expect them to saw the thing in half, but how else are they going to put in the little seats and the steering column when the gull-wing doors aren’t real?

This build is all about unbelievable craftsmanship and deft but daring use of hand tools. Although this totally qualifies as an open source how-to video, you’d have to be quite the sorcerer to pull this one off. Zoom past the break (if you haven’t already) and check out this amazing build.

Disposable lighters are dirt cheap, but they get the job done and you can always see how much gas is left in the tank. On the other hand, a refillable lighter is just that, and if you build it yourself, you can make it actuate like a cap gun.

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Shipping A CRT: Lessons Learned

April 29, 2021 by Chris Lott 75 Comments

Old CRT computer enthusiast [x86VileR] recently tracked down an IBM 5153 monitor for which he had been searching several years. Unfortunately shipping a heavy glass CRT isn’t easy. In fact, it took [VileR] three tries to get a functioning monitor delivered intact and working. The first one seemed reasonably protected in its packaging, but arrived so banged up that the CRT had become dislodged inside the monitor and the neck broke off! The second attempt was packaged even better, and he was sure it would arrive problem-free. Alas, it too arrived all banged up and broken.

This one clearly had superior packaging, so I find it difficult to account for this truly stupendous level of damage. The most promising theory is that several people jumped on it simultaneously, just before the delivery truck ran it over. As my friend put it, it would’ve arrived in better shape if he had just smashed it himself before boxing it up.

Double-boxing appears to be the answer, although it might result in a box too large to ship depending on your courier’s rules. Short of building custom wooden crates, do you have any packing tips for shipping heavy and fragile items? Thanks to [J.R. Dahlman] for sending us the tip.

Wireless MicroPython Programming With Thonny

April 29, 2021 by Chris Lott 11 Comments

I’ve been playing with a few MicroPython projects recently on several different embedded platforms, including a couple of ESP32 WiFi modules. There are various ways to program these modules:

Use a serial terminal and ampy (maintained by [devxpy] since being dropped by Adafruit in 2018).
If you use Pycom boards or WiFy firmware, there are the pymakr plugins for Atom and Visual Studio.
If you prefer the command-line like me, there is rshell by one of the top MicroPython contributors [Dave Hylands].

For over a year, I have been quite happy with rshell until I started working on these wireless nodes. Being lazy, I want to tinker with my ESP32 modules from the sofa, not drag my laptop into the kitchen or balcony to plug up a USB cable. Can’t I work with them wirelessly?

Well, you can use WebREPL. While its functional, it just didn’t strike my fancy for some reason. [Elliot] mentioned in a recent podcast that he’s using telnet to access his wireless nodes, but he’s using esp-link on an ESP8266, which means throwing another chip into the mix.

The Thonny IDE

I had all but given up when by chance I saw this video on the Dronebot Workshop channel about running MicroPython on the new Raspberry Pi Pico boards. Bill was using Thonny, a Python IDE that is popular in the education community. Thonny was introduced in 2015 by Aivar Annamaa of the University of Tartu in Estonia. Thonny was designed to address common issues observed during six years of teaching Python programming classes to beginners. If you read about the project and its development, you’ll see that he’s put a lot of effort into making Thonny, and it shows.

Leaning about Thonny got me curious, and after a little digging I discovered that it has WebREPL support for MicroPython right out-of-the-box. Although this is a new feature and classified as experimental, I found it reasonably stable to use and more than adequate for home lab use. Continue reading “Wireless MicroPython Programming With Thonny” →

Guide To Mastering OpenSCAD Costs Roughly The Same As OpenSCAD

April 17, 2021 by Kristina Panos 36 Comments

OpenSCAD is a fantastic free tool for 3D modeling, but it’s far less intuitive to use for non-programmers than mouse-driven programs such as Tinkercad. Powerful as it may be, the learning curve is pretty steep. OpenSCAD’s own clickable cheat sheet and manual comes in handy all the time, but those are really more of a reference than anything else. Never fear, because [Jochen Kerdels] had quite the productive lockdown and wrote a free comprehensive guide to mastering OpenSCAD.

[Jochen]’s book opens with a nice introduction to OpenSCAD and it’s user environment and quickly moves into 10 useful projects of increasing complexity that start with simple stuff like wall anchors and shelf brackets and ends with recursive trees.

There are plenty of printing tips along the way to help realize these projects with minimum frustration, and the book wraps up by covering extra functions not expressly used in the projects.

Of course, you could always support [Jochen]’s Herculean effort by buying the print edition and forcing yourself to type everything in instead of copy/pasting, or give it to someone to introduce them to all the program has to offer.

Need help mastering OpenSCAD workflow? We’ve got that. Just want to make some boxes or airfoils? We have those in stock, too.

Main and thumbnail images via [Devlin Thyne]

Three Ways To Detect The Silver Ball

April 16, 2021 by Kristina Panos 13 Comments

We speak from experience when we say that making pinball targets is harder than you might think. The surface area of the part of the ball that touches is oh-so-small, and you really need to have gravity on your side for best results. Luckily, [TechnoChic] did the work for us and came up with these three versatile sensor designs that would be good for any game, not just pinball. They all use fresh, pristine cardboard from the Bezos Barn and a conductive fabric tape made by Brown Dog Gadgets that they call maker tape.

With the possible exception of not being solderable (can you solder it? ours hasn’t showed up yet), maker tape is seemingly superior to copper tape because it is designed to be conductive in the Z-direction, and if you’ve ever laid out a copper tape circuit, you know that tape overlaps are pretty much par for the course.

First on the list is the track switch, which we think is pretty much necessary. After all, what fun is a pinball machine without at least one pair of rails to ride? Might as well score some points at the same time. This one looks to be the trickiest since the rails have to be consistently spaced, otherwise the ball will fall. The drawbridge target uses a cardboard hinge and the weight of the ball to force two pieces of tape together to complete the circuit.

The flappy hole target is probably our favorite because it’s the most adaptable. You could use it for all kinds of things, like getting the ball to a basement level of a pinball game, or if you want to be evil, set it up in the drain area and deduct points every time you lose the ball, or just use it to trigger the next ball to drop. This one would also be really good for something like Skee-Ball and would really keep the BoM cost down compared to say, IR break-beam targets or coin slot switches.

You can check out these sensors in a brief demo after the break, and then see how [TechnoChic] put these ideas to use in this winter-themed pinball machine we showed you a few weeks ago.

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You Need An Automated Overhead Camera Assistant

April 14, 2021 by Kristina Panos 13 Comments

It’s 2021. Everyone and their mother is filming themselves doing stuff, and a lot of it is super cool content. But since most of us have to also work the video capture devices ourselves, it can be difficult to make compelling footage with a single, stationary overhead view, especially when there are a lot of steps involved. A slider rig is a good start, but the ability to move the camera in three dimensions programmatically is really where it’s at.

[KronBjorn]’s excellent automated overhead camera assistant runs on an Arduino Mega and is operated by typing commands in the serial monitor. It can pan ±20° from straight down and moves in three axes on NEMA-17 stepper motors. It moves really smoothly, which you can see in the videos after the break. The plastic-minimal design is interesting and reminds us a bit of an ~~ophthalmoscope~~ phoropter — that’s that main rig at the eye doctor. There’s only one thing that would make this better, and that’s a dedicated macro pad.

If you want to build your own, you’re in luck — there’s quite a lot of detail to this project, including a complete BOM, all the STLs, code, and even assembly videos of the 3D-printed parts and the electronics. Slide past the break to check out a couple of brief demo videos.

Not enough room for a setup like this one? Try the pantograph version.

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