Hot Wire Foam Cutter Does Circles, Too

Foam is all kinds of useful, but trying to cut it with scissors or a serrated plastic knife is usually an exercise in futility. What you really need is a hot wire for nice clean cuts. [Elite Worm] built a hot wire foam cutter that can cut any type of foam with ease, be it Styrofoam or grey craft foam.

There are a ton of ways to heat up a taut piece of nichrome wire, but few of them are as good looking as this one. [Elite Worm] designed and printed a table with an adjustable fence so it can be used like a table saw. There is also a circle-cutting jig that looks really handy.

This design uses a 12 V power regulator to heat up a piece of tension-adjustable nichrome wire for buttery smooth cuts. This thing looks fantastic all the way down to the cable management scheme. All the files are available on Thingiverse if you want to build one for yourself, but you’ll need to use something other than PLA.

This wire cutter is pretty versatile, but you could go even smaller with a handheld version, or build a larger, CNC-based machine.

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Smart Screen Heal Thyself

The Korea Institute of Science and Technology (KIST) have announced a transparent, self-healing polyimide material designed for smart phone screens. A KIST team from the Composite Materials Applications Research Center led by Dr Yong-chae Jung and a team at Yonsei University’s Electronics Materials Lab led by Dr Hak-soo Han collaborated on this project. While the goal was to improve the material used in folding smart phone screens, the results seem applicable to all glass screens that are prone to cracks and scratches.

This new material can heal itself in 12 hours at room temperature, even faster under UV light. As we understand it, many micro-balloons of flaxseed oil are impregnated on the surface and break open if the material is damaged. Thus liberated, the oil is now free to flow into and fill up the cracks. We imagine it’s like repairing windshield cracks, but on a much smaller scale.

The idea is to eliminate the need for user-added screen protection films and increase the life of your phone screen. But cynical people might wonder if smart phone manufacturers will embrace this new technology with much enthusiasm — after all, if people use their phones longer it might cut into sales. Those with access to academic journals can read the report here.

Fridge Compressor Turned Into Capable Little Four-Stroke Engine

Never underestimate the power of a well-stocked junk bin. Along with a TIG welder and mechanical ingenuity bordering on genius-level, all of which come to bear on this fridge compressor to four-stroke engine build.

The video posted by [Let’s Learn Something] is long, but watching it at double speed doesn’t take away much from the enjoyment. By using a piston-type compressor, a lot of the precision machining is already taken care of here. Adding the intake and exhaust valves, camshaft, timing chain, carburetor, and ignition system are still pretty challenging tasks, though. We loved the home-made timing chain sprockets, made with nothing more than a drill and an angle grinder. In a truly inspired moment, flat-head screws are turned into valves, rocker arms are fabricated from bits of scrap, and a bolt becomes a camshaft with built-up TIG filler. Ignition and carburetion are cobbled together from more bits of scrap, resulting in an engine that fired up the first time — and promptly melted the epoxy holding the exhaust header to the cylinder head.

Now, compressor-to-engine conversions aren’t exactly new territory. We’ve seen both fridge compressors and automotive AC compressors turned into engines before. But most of what we’ve seen has been simple two-stroke engines. We’re really impressed with the skill needed to bring off a four-stroke engine like this, and we feel like we picked up quite a few junk-box tips from this one.

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European Right To Repair: Poor Repairability Shamed With Rating System

Happily the right to repair movement is slowly gaining ground, and recently they’ve scored a major success in the European Parliament that includes a requirement that products be labelled with expected lifetime and repairability information, long-term availability of parts, and numerous measures aimed at preventing waste.

… including by requiring improved product information through mandatory labelling on the durability and reparability of a product (expected lifetime, availability of spare parts, etc.), defining durability and reparability as the main characteristics of a product…

Even the UK, whose path is diverging from the EU due to Brexit, appears to have a moment of harmony on this front. This builds upon existing rights to repair in that devices sold in Europe will eventually have to carry a clearly visible repair score to communicate the ease of repairability and supply of spare parts, making a clear incentive for manufacturers to strive for the highest score possible.

We live in an age in which our machines, appliances, and devices are becoming ever more complex, while at the same time ever more difficult to repair. Our community are the masters of fixing things, but even we are becoming increasingly stumped in the face of the latest flashy kitchen appliance or iDevice. The right to repair movement, and this measure in particular, seeks to improve the ability of all consumers, not just us hackers, to makebuying decisions for better products and lower environmental impact.

With a population of around 450 million people spread across 27 member countries, the EU represents a colossal market that no manufacturer can afford to ignore. Therefore while plenty of other regions of the planet have no such legislation this move will have a knock-on effect across the whole planet. Since the same products are routinely sold worldwide it is to be expected that an improvement in repairability for European markets will propagate also to the rest of the world. So when your next phone has a replaceable battery and easier spares availability, thank the EU-based right to repair campaigners and some European lawmakers for that convenience.

European Parliament from EU, CC BY 2.0.

Templateize Your Timetable With EPaper Templates

To date, e-paper technology has been great for two things, displaying static black and white text and luring hackers with the promise of a display that is easy on the eyes and runs forever. But poor availability of bare panels has made the second (we would say more important) goal slow to materialize. One of the first projects that comes to mind is using such a display to show ambient information like a daily summary weather, train schedules, and calendar appointments. Usually this means rolling your own software stack, but [Christopher Mullins] has put together a shockingly complete toolset for designing and updating such parameterized displays called epaper_templates.

To get it out of the way first, there is no hardware component to epaper_templates. It presupposes you have an ESP32 and a display chosen from a certain list of supported models. A quick search on our favorite import site turned up a wide variety of options for bare panels and prebuilt devices (ESP32 and display, plus other goodies) starting at around $40 USD, so this should be a low threshold to cross.

Once you have the device, epaper_templates provides the magic. [Christopher]’s key insight is that an ambient display is typically composed of groups of semi-static data displayed in a layout that never changes. The only variation is updates to the data which is fully parameterized: temperature is always integer Fahrenheit, train schedules are lists of minutes and hours, etc. Layouts like this aren’t difficult to make, but require the developer to reimplement lots of boilerplate. To make them easy to generate, epaper_templates provides a fully featured web UI to let the user freely customize a layout, then exports it as JSON which the device consumes.

The sample layout configured in the video below

The web UI is shockingly capable, especially for by the standards of the embedded web. (Remember it’s hosted on the ESP32 itself!) The user can place text and configure fonts and styles. Once placed, the text can be set to static strings or tied to variables, and if the string is a timestamp it can be formatted with a standard strftime format string.

To round out the feature set, the user can place images and lines to divide the display. Once the display is described, everything becomes simple to programmatically update. The ESP can be configured to subscribe to certain MQTT topics from which it will receive updates, or if that is too much infrastructure there is a handy REST API which accepts JSON objects containing variables or bitmaps to update on device.

We’re totally blown away by the level of functionality in epaper_templates! Check out the repo for more detail about its capabilities. For a full demo which walks through configuration of a UI with train arrival times, weather, both instant temperature and forecast with icons, and date/time check out the video after the break. Source for the example is here, but be sure to check out examples/ in the repo for more examples.

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A Case For Project Part Numbers

Even when we share the design files for open source hardware, the step between digital files and a real-world mechatronics widget is still a big one. That’s why I set off on a personal vendetta to find ways to make that transfer step easier for newcomers to an open source mechantronics project.

Today, I want to spill the beans on one of these finds: part numbers, and showcase how they can help you share your project in a way that helps other reproduce it. Think of part numbers as being like version numbers for software, but on real objects.

I’ll showcase an example of putting part numbers to work on one of my projects, and then I’ll finish off by showing just how part numbers offer some powerful community-building aspects to your project.

A Tale Told with Jubilee

To give this idea some teeth, I put it to work on Jubilee, my open source toolchanging machine. Between October 2019 to November 2020, we’ve slowly grown the number of folks building Jubilees in the world from 1 to more than 50 chatting it up on the Discord server. Continue reading “A Case For Project Part Numbers”

Clone Console Cribs Ben Heck’s Classic SNES Caché

“I don’t get mad when people rip me off. I actually think its kinda cool, because imitation is the sincerest form of flattery.” — Ben Heckendorn

For some “hacking things together” can mean heavily borrowing from other’s work in order to make a new, derivative work. Though longtime hardware hacker, Ben Heckendorn, didn’t expect one of his early SNES handheld projects to become the inspiration for a Famicom-style clone console. There have been a number of clone consoles available online for years, and all have been made to varying levels of build quality. The subject clone console in question is called the Easegmer 12-bit Retro Console, so [Ben] decided to record his teardown of the handheld borrowing from his original design. (Video, embedded below.)

The Easegmer handheld has a “surprising” list of features according to its packaging including: sports games, logic games, memoyr games, USB charger management, double power supply option, and dirunal double backlight option. All big (and slightly misspelled) promises though the most egregious claim has to be that, “No violent games, your child’s body and mind get full exercise.”. The statement may have a modicum of truth to it, except for the fact that game 84 of 220 is literally named “Violent”. Dunking aside, the handheld does feature a standard size rechargeable battery in addition to the option of powering the device with three AAA batteries. There’s even a “fun size” screwdriver and a few replacement screws included which is more than you can say for most modern electronics.

It has been almost twenty years after [Ben] originally published his SNES portable project on his website. So as a long awaited follow-up, [Ben] plans to make a “meta-portable”. This meta portable will start with the Adobe Illustrator files he kept from that SNES portable in 2001 and incorporate pieces of the Easegmer clone console. Thus spawning a new clone of the clone of his clone…or whatever that project ends up being its sure to be worth repeating.

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