Automated Blinds Opener On The Cheap

May 27, 2025 by Matt Varian 7 Comments

We love seeing hacks that involve salvaging parts from what you have on hand to make a new project work, and this project is a great example of that. [Simon], in a quick weekend build, created an automated blinds opener using parts he had available.

The project began with the desire to have his blinds open slowly and silently, gradually letting in more light. To accomplish this, a few key components were needed, including a motor with a gearbox to provide the torque required to actuate the blinds and a magnetic encoder to track their progress. To isolate vibrations and keep the system silent, the motor is mounted using a silicone motor mount that he salvaged from a broken water flosser.

The printed holder for the magnetic encoder is a nice touch.

To mount the motor to the wall near the window, he used some 3D printed parts. A clever combination of surgical silicone tubing and silicone tape attaches the motor to the window blind shaft while limiting vibration transfer, keeping things quiet. [Simon] advises against using magnetic encoders as he did, noting that while he had them on hand and made them work, the magnetic shaft’s misalignment with the encoders makes it a less-than-ideal approach. Nevertheless, he got it working.

Automating blinds is a fairly common project around these parts, made all the more accessible with clever 3D printed mechanisms. We’ve even seen variations that can be used in rentals, dorms, and other places were permanent modifications need to be avoided.

PCB Renewal Aims To Make Old Boards Useful Again

May 4, 2025 by Lewin Day 13 Comments

We’ve all made a few bad PCBs in our time. Sometimes they’re recoverable, and a few bodge wires will make ’em good. Sometimes they’re too far gone and we have to start again. But what if you could take an existing PCB, make a few mods, and turn it into the one you really want? That’s what “PCB Renewal” aims to do, as per the research paper from [Huaishu Peng] and the research group at the University of Maryland.

*The plugin quantifies resource and time savings made by reusing an old board.*

The concept is straightforward — PCB Renewal exists as a KiCad plugin that can analyze the differences between the PCB you have and the one you really want. Assuming they’re similar enough, it will generate toolpaths to modify the board with milling and epoxy deposition to create the traces you need out of the board you already have.

Obviously, there are limitations. You’ll never turn a PlayStation motherboard into something you could drop into an Xbox with a tool like this. Instead, it’s more about gradual modifications. Say you need to correct a couple of misplaced traces or missing grounds, or you want to swap one microcontroller for a similar unit on your existing board. Rather than making brand new PCBs, you could modify the ones you already have.

Of course, it’s worth noting that if you already have the hardware to do epoxy deposition and milling, you could probably just make new PCBs whenever you need them. However, PCB Renewal lets you save resources by not manufacturing new boards when you don’t have to.

We’ve seen work from [Huaishu Peng]’s research group before, too, in the form of an innovative “solderless PCB”.

Continue reading “PCB Renewal Aims To Make Old Boards Useful Again” →

Have Li-ion Batteries Gone Too Far?

March 13, 2025 by Navarre Bartz 84 Comments

The proliferation of affordable lithium batteries has made modern life convenient in a way we could only imagine in the 80s when everything was powered by squadrons of AAs, or has it? [Ian Bogost] ponders whether sticking a lithium in every new device is really the best idea.

There’s no doubt, that for some applications, lithium-based chemistries are a critically-enabling technology. NiMH-based EVs of the 1990s suffered short range and slow recharge times which made them only useful as commuter cars, but is a flashlight really better with lithium than with a replaceable cell? When household electronics are treated as disposable, and Right to Repair is only a glimmer in the eye of some legislators, a worn-out cell in a rarely-used device might destine it to the trash bin, especially for the less technically inclined.

[Bogost] decries “the misconception that rechargeables are always better,” although we wonder why his article completely fails to mention the existence of rechargeable NiMH AAs and AAAs which are loads better than their forebears in the 90s. Perhaps even more relevantly, standardized pouch and cylindrical lithium cells are available like the venerable 18650 which we know many makers prefer due to their easy-to-obtain nature. Regardless, we can certainly agree with the author that easy to source and replace batteries are few and far between in many consumer electronics these days. Perhaps new EU regulations will help?

Once you’ve selected a battery for your project, don’t forget to manage it if it’s a Li-ion cell. With great power density, comes great responsibility.

USB-C For Hackers: Reusing Cables

November 21, 2024 by Arya Voronova 83 Comments

Your project needs a cable, and since USB-C cables are omnipresent now, it’s only natural to want to reuse them for your evil schemes. Ever seen USB 3.0 cables used for PCIe link carrying duty? It’s because USB 3.0 cables are built to a reasonably high standard, both sockets and cables are easy to find, and they’re cheap. Well, USB-C cables beat USB 3.0 cables by all possible metrics.

Let’s go through USB-C cable reuse in great detail, and see just what exactly you get when you buy either a gas station C-C USB 2.0 cable, or, the fanciest all-features-supported 240 W Thunderbolt cable that money can buy. Looking for a cable to cut, or something to pass a seriously high-speed link? You’re reading the right article.

The Omnipresent Cables

USB-A to USB-C cables are the least interesting. They’re equivalent to a microUSB to USB-A cable, except there’s a resistor on the USB-C plug, connected from VBUS to one of the CC pins. That’s it. The cable contains four conductors, there’s really not much new. Save these cables for all the devices still built without the 5.1 kΩ resistors.

Now, a USB-C to USB-C cable – let’s say, 60 W max, the default USB-C cable capability. If your cable says anything less than 60 W, say, “2 A” or “15 W”, that’s a lie – it can handle 60 W no problem, all USB-C to C cables can do 60 W. This cable is also cool – for one, it has five conductors; GND, VBUS, D+, D-, and CC. Two of them (GND and VBUS) are guaranteed to be thick enough to carry 3 A without much voltage drop if any, too!

Continue reading “USB-C For Hackers: Reusing Cables” →

Hacker Tactic: Building Blocks

October 24, 2024 by Arya Voronova 12 Comments

The software and hardware worlds have overlaps, and it’s worth looking over the fence to see if there’s anything you missed. You might’ve already noticed that we hackers use PCB modules and devboards in the same way that programmers might use libraries and frameworks. You’ll find way more parallels if you think about it.

Building blocks are about belonging to a community, being able to draw from it. Sometimes it’s a community of one, but you might just find that building blocks help you reach other people easily, touching upon common elements between projects that both you and some other hacker might be planning out. With every building block, you make your or someone else’s next project quicker, and maybe you make it possible.

Sometimes, however, building blocks are about being lazy.

Continue reading “Hacker Tactic: Building Blocks” →

No Solder! Squeeze Your Parts To The PCB

May 11, 2024 by Elliot Williams 30 Comments

What’s solder for, anyway? It’s just the stuff that sticks the parts to the PCB. If you’re rapid prototyping, possibly with expensive components, and want to be able to remove chips from the board easily when you spin up the next iteration, it would be great if you didn’t have to de-solder them to move on. If only you could hold the parts without the solder…

That’s exactly the goal behind [Zeyu Yan] et al’s SolderlessPCB, which uses custom 3D printed plastic covers to do the holding. And it has the knock-on benefit of serving as a simple case.

In their paper, they document some clever topologies to make sure that the parts are held down firmly to the board, with the majority of the force coming from screws. We especially like the little hold-down wings for use with SMD capacitors or resistors, although we could absolutely see saving the technique exclusively for the more high value components to simplify design work on the 3DP frame. Still, with the ability to automatically generate 3D models of the board, parts included, this should be something that can be automated away.

The group is doing this with SLA 3D printing, and we imagine that the resolution is important. You could try it with an FDM printer, though. Let us know if you do!

This is the same research group that is responsible for the laser-cut sheet-PCB origami. There’s clearly some creative thinking going on over there.

EcoEDA Integrates Your Junk Bin Into Your Designs

October 28, 2023 by Dan Maloney 26 Comments

If you’re like us, there’s a creeping feeling that comes over you when you’re placing an order for parts for your latest project: Don’t I already have most of this stuff? With the well-stocked junk bins most of us sport and the stacks of defunct electronics that are almost always within arm’s length, chances are pretty good you do. And yet, we always seem to just click the button and place a new order anyway; it’s just easier.

But what if mining the treasure in your junk bin was easier? If you knew right at design time that you had something in your stash you could slot into your build, that would be something, right? That’s the idea behind ecoEDA, a Python-based KiCAD plugin by [Jasmine Lu], [Beza Desta], and [Joyce Passananti]. The tool integrates right into the schematic editor of KiCAD and makes suggestions for substitutions as you work. The substitutions are based on a custom library of components you have on hand, either from salvaged gear or from previous projects. The plug-in can make pin-for-pin substitutions, suggest replacements with similar specs but different pinouts, or even build up the equivalent of an integrated circuit from available discrete components. The video below gives an overview of the tool and how it integrates into the design workflow; there’s also a paper (PDF) with much more detail.

This seems like an absolutely fantastic idea. Granted, developing the library of parts inside all the stuff in a typical junk bin is likely the biggest barrier to entry for something like this, and may be too daunting for some of us. But there’s gold in all that junk, both literally and figuratively, and putting it to use instead of dumping it in a landfill just makes good financial and environmental sense. We’re already awash in e-waste, and anything we can do to make that even just a little bit better is probably worth a little extra effort. Continue reading “EcoEDA Integrates Your Junk Bin Into Your Designs” →