IKEA’s Billy Bookshelf Is A Useful 3D Printing Enclosure

August 29, 2023 by 49 Comments

The results from your 3D printer may be improved if you use a dedicated enclosure for the job. This is particularly helpful for printing certain materials which are more sensitive to cold drafts or other thermal disruptions to the working area.  If you want an elegant solution to the problem, consider getting yourself an IKEA Billy bookshelf, says [wavlew].

The Billy makes a remarkably elegant 3D printing workstation, overall. It’s got a nifty slide-out drawer that makes a perfect mounting point for a 3D printer. It lets you slide out the printer for maintenance, using the controls, or extracting finished prints. It also naturally features plenty of storage for your filament, tools, and other accoutrements. When it comes to the business of actually printing though, you just slide the printer inside and shut the door. Its thermal and noise isolating performance can also be further improved by adding a silicone door seal.

We love this idea. Too often, 3D printers are left chugging away on messy desks, where they’re subject to blasts from AC vents and other disruptions. Having everything tidily tucked away in a cupboard neatens things significantly, and could also prove helpful if you pursue fume extraction, too.

If you’ve identified any other nifty maker applications for IKEA furniture, be sure to let us know!

Checking Belt Tension Gets Easier For (Some) Prusa 3D Printers

August 29, 2023 by 22 Comments

Belts on a 3D printer should be tight enough, but not too tight. That can be an iffy thing to get right for someone who lacks familiarity with CNC platforms. Prusa Research aims to make it a bit easier with a web app that can measure tension via your mobile phone’s microphone and diagnose belt tightness, at least for their MK4 and XL printers.

Using different tools to analyze belt tightness (including belt acoustics) have been tried in the past with mixed results, but this is a pretty focused approach that aims to give exact guidance for specific printer models. It’s pretty useful to provide someone with a reliable go/no-go number, after all.

What happens to a printer if a belt’s tension is not right? Well, there’s actually a pretty forgiving range within which the printer will mostly work fine, but not as well as it could be. Loose belts can have novices chasing other problems, and overly-tightened belts definitely put extra strain on parts. It’s one of those things that’s worth a little extra work to get right.

3D printable tension meter is a different option for Prusa MK3 and Mini printers, if one has some Prusament PETG to print it in.

Everything about belt tension for Prusa printers is covered in their documentation, but did you know there’s also neat 3D printable tension meter for Prusa MK3 and Mini printers? It’s meant to be printed in Prusament PETG (printing in other materials may have different results) but it’s a pretty neat idea for a tool.

If you have a Prusa MK4 or XL and want to try their new method, go here and allow access to your device’s microphone. Then select a printer model and an axis to test. Gently strum the upper part of the belt (avoid touching the bottom belt in the process) and watch live results telling you whether the belt is too tight, too loose, or just right. Prusa have a video demonstrating the process, also embedded below.

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A WiFi RGB Camera Grip Is Probably Not Ideal For Night Shoots

August 29, 2023 by 1 Comment

RGB LEDs can be found on everything from motherboards to sticks of RAM these days. [dslrdiy] wanted to bring this same visual flair to his camera setup, so built what he’s calling the world’s first RGB camera grip.

The build is based on an existing off-the-shelf camera grip. It’s disassembled for the build, with a pair of 18650 lithium batteries installed inside as a power supply. They run a small DC-DC converter, which powers a Raspberry Pi Zero and a WS2812B LED strip which provides the lovely colorful lighting effects. The LEDs light up a translucent spacer installed in the camera grip solely for the purpose of aesthetics.

So far, so straightforward. However, [dslrdiy] also implemented one more useful feature. The Pi Zero is able to scrape photos from the camera, and automatically load them on to a Windows network share. That’s a nice zero-fuss way to get pictures off your camera when you return to your home network.

We’re not sure too many professional photographers will rush after the RGB grip, as it’s often poor practice to introduce strange uncontrolled colorful lights into a scene. However, the wireless tethering feature does seem attractive depending on your usual workflow. Video after the break.

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Retro Gadgets: The 1974 Breadboard Project

August 29, 2023 by 36 Comments

It is hard to imagine experimenting with electronics without the ubiquitous solderless breadboard. We are sure you have a few within arm’s reach. The little plastic wonders make it easy to throw together a circuit, try it, and then tear it down again. But, surprisingly, breadboards of that type haven’t always been around, and — for a while — they were also an expensive item. Maybe that’s what motivated [R. G. Cooper] to build Slip-n-Clip — his system for quickly building circuits that he published in a 1974 edition of the magazine Elementary Electronics.

The system isn’t really what you would think of as a breadboard today, but it was effective and certainly cheap to build. The biggest problem? It wasn’t something you’d use with DIP ICs. But in the early 1970s, you might not be building very much with ICs, and the ones you used might be in oddball transistor-like packages. Things were strange in the 70s!

A Brief History of Breadboards

In the very old days, people built radios and such on wooden substrates that were actually bread-cutting boards. That’s where the name came from. It was common to draw a diagram with the physical layout you had in mind, glue it to the board, and use it as a guide for building and troubleshooting. Wood was easy to drill and cut. A nail or a thumbtack would make dandy terminals. Probably the last time we saw that done was about a dozen years ago in Make Magazine. Even then, it was only a novelty — few people still build circuits like this, but you can see how [Colin] did it in the video below.

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WiFi, PWM Backlight, And Graphics On Updated Chumby Kernel

August 29, 2023 by 5 Comments

For some, the Chumby was a peek at what could have been. That vision never died for [Doug Brown], and he has been working tirelessly on bringing mainline Linux kernel support to the customizable smart display. He has posted several updates but recently got graphics and the PWM backlight working.

Of course, we covered when [Doug] first started working on the new kernel, so it’s high time we revisited the progress. The WiFi hardware uses a Marvell 88W8686 chipset, which talks over the SDIO bus, so it’s a matter of convincing the libertas driver to talk to it. With a USB to Ethernet adapter, [Doug] could boot new kernels over NFS, so he didn’t have to walk over to swap the SD card. After dealing with an unhandled fault when trying to read the SDHCI_HOST_VERSION register, [Doug] had access points showing up in NetworkManager but could not connect. As a nasty hack, he temporarily removed the interrupts and switched to polling in the driver. While that worked, it would never get upstreamed. A critical interrupt was being dropped, and commands went out of sequence. A second, perhaps ugly hack, read a register after acknowledging an SDIO interrupt, which seemed to work. But it was still a hack, and [Doug] wanted something cleaner. In a blind stroke of luck, he found the errata online and noticed that it mentioned that an interrupt could be missed when a signal was asserted. After following the workaround with a lot of head-scratching and deep diving, he had a fully working WiFi driver.

Graphics were a more straightforward endeavor compared to WiFi. He enabled the simpledrm driver (similar to simplefb) but using Direct Rendering Manager. He had a working panel that could run Qt apps by adding the frame buffer to the device tree with the correct compatible string, registers, and data. However, there was a Vivante GC300 graphics accelerator onboard that he wanted to use. A driver for Vivante GPUs already exists in the kernel, but after enabling it, the driver detects the GC300 and then starts complaining. He discovered that older revisions of the GC300 (like the ones found in Chumbys) mapped registered at different addresses and didn’t set some bits in their idle registers. Of course, just loading a GPU driver isn’t quite enough. He modified an x11 server that supported Vivante accelerators to support the GC300.

For hacking purposes, [Doug] set the backlight GPIO high. While easy to see, perhaps not the best for a device meant to blend in. The PAX166 comes with PWM hardware, though confusingly, it has two PWM modes for pin 84. PWM1 and PWM2 share some common clock and reset bits in a decidedly undocumented way. PWM2 doesn’t work until you configure and then turn off PWM1. However, the backlight turned off once out of UBoot and into Linux. Linux re-initialized the hardware too quickly, causing the device to freak out. This was solved using the abrupt shutdown register.

It’s a journey through debugging, Linux internals, and device tree hackery. Perhaps the most incredible thing is that these changes are submitted for upstreaming to the Linux kernel, with many landing in Linux 6.2. While it’s a shame new Chumbys aren’t being made, making your own smart display has never been easier.

The 2003 Northeast Blackout And The Harsh Lessons Of Grid Failures

August 29, 2023 by 87 Comments

The grid failure in 2003 which reverted much of the eastern US and Canada back to a pre-electrification era may be rather memorable, yet it was not the first time that a national, or even international power grid failed. Nor is it likely that it will be the last. In August of 2023 we mark the 20th anniversary of this blackout which left many people without electricity for up to three days, while costing dozens of  people their lives. This raises the question of what lessons we learned from this event since then.

Although damage to transmission lines and related infrastructure is a big cause of power outages – especially in countries where overhead wiring is the norm – the most serious blackouts involve the large-scale desynchronization of the grid, to the point where generators shutdown to protect themselves. Bringing the grid back from such a complete blackout can take hours to days, as sections of the grid are reconnected after a cascade scenario as seen with the 2003 blackout, or the rather similar 1965 blackout which affected nearly the same region.

With how much more modern society relies today on constant access to electrical power than it did twenty, let alone fifty-eight years ago, exactly how afraid should we be of another, possibly worse blackout?

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Blame It On The Sockets: Forensic Analysis Of The Arecibo Collapse

August 29, 2023 by 58 Comments

Nearly three years after the rapid unplanned disassembly of the Arecibo radio telescope, we finally have a culprit in the collapse: bad sockets.

In case you somehow missed it, back in 2020 we started getting ominous reports that the cables supporting the 900-ton instrument platform above the 300-meter primary reflector of what was at the time the world’s largest radio telescope were slowly coming undone. From the first sign of problems in August, when the first broken cable smashed a hole in the reflector, to the failure of a second cable in November, it surely seemed like Arecibo’s days were numbered, and that it would fall victim to all the other bad luck we seemed to be rapidly accruing in that fateful year. The inevitable finally happened on December 1, when over-stressed cables on support tower four finally gave way, sending the platform on a graceful swing into the side of the natural depression that cradled the reflector, damaging the telescope beyond all hope of repair.

The long run-up to the telescope’s final act had a silver lining in that it provided engineers and scientists with a chance to carefully observe the failure in real-time. So there was no real mystery as to what happened, at least from a big-picture perspective. But one always wants to know the fine-scale details of such failures, a task which fell to forensic investigation firm Thornton Tomasetti. They enlisted the help of the Columbia University Strength of Materials lab, which sent pieces of the failed cable to the Oak Ridge National Laboratory’s High Flux Isotope reactor for neutron imaging, which is like an X-ray study but uses streams of neutrons that interact with the material’s nuclei rather than their electrons.

The full report (PDF) reveals five proximate causes for the collapse, chief of which is “[T]he manual and inconsistent splay of the wires during cable socketing,” which we take to mean that the individual strands of the cables were not spread out correctly before the molten zinc “spelter socket” was molded around them. The resulting shear stress caused the zinc to slowly flow around the cable strands, letting them slip out of the surrounding steel socket and — well, you can watch the rest below for yourself.

As is usually the case with such failures, there are multiple causes, all of which are covered in the 300+ page report. But being able to pin the bulk of the failure on a single, easily understood — and easily addressed — defect is comforting, in a way. It’s cold comfort to astronomers and Arecibo staff, perhaps, but at least it’s a lesson that might prevent future failures of cable-supported structures.

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