Many of us use touch pads daily on our laptops, but rarely do we give much thought about what they really do. In fact they are a PCB matrix of conductive pads, with a controller chip addressing it and sensing the area of contact. Such a complex and repetitive pattern can be annoying to create by hand in an EDA package, so [Timonsku] has written a script to take away the work.

It starts with an OpenSCAD script (originally written by Texas Instruments, and released as open source) that creates a diamond grid, which can be edited to the required dimensions and resolution. This is then exported as a DXF file, and the magic begins in a Python script. After adjustment of variables to suit, it finishes with an Eagle-compatible board file which should be importable into other EDA packages.

We’ve never made a touchpad ourselves, but having dome other such repetitive PCB tasks we feel the pain of anyone who has. Looking at this project we’re struck by the thought that its approach could be adapted for other uses, so it’s one to file away for later.

This isn’t the first home-made touchpad project we’ve brought you.

For those who love systems and structure, owning a 19-inch rack with just one slot filled is just not it. But what if the rest of your gear isn’t 19-inch? Well, then you go out and make it so, just like [Cal Bryant] did recently.

The goal was to consolidate multiple devices — DAC, input selector, streamer, and power routing — into a single 2U rackmount unit. His first attempts involved drilling 1U panels to attach gear with removable faceplates. That worked, but not all devices played nice. So his next step became a fully custom enclosure with CAD-modeled brackets and front panels.

OpenSCAD turned out to be a lifesaver, letting [Cal] design modular mounting solutions. Exporting proper circles for CNC turret punching however appeared to be a nightmare. It was FreeCAD to the rescue for post-processing. After some sanding and auto-shop painting, the final faceplate looked factory-made.

Custom switch boxes for power and audio routing keep things tidy, housing everything from USB to XLR inputs. A 4-pole switch even allows seamless swapping between his DAC and DJ controller, while UV-printed graphics bring the finishing touch to this project. For those looking to clean up their Hi-Fi setup (or just love modding for the sake of it), there’s a lot to learn from this build.

If buying a rack is not within your budget, you could start with well-known IKEA LACK furniture.

Not that it’s the kind of thing that pops into your head often, but if you ever do think of a cyanotype print, it probably doesn’t conjure up thoughts of modern technology. For good reason — the monochromatic technique was introduced in the 1840s, and was always something of a niche technology compared to more traditional photographic methods.

The original method is simple enough: put an object or negative between the sun and a UV-sensitive medium, and the exposed areas will turn blue and produce a print. This modernized concept created by [Gabe] works the same way, except both the sun and the negative have been replaced by a lightly modified resin 3D printer.

A good chunk of the effort here is in the software, as [Gabe] had to write some code that would take an image and turn it into something the printer would understand. His proof of concept was a clever bit of Python code that produced an OpenSCAD script, which ultimately converted each grayscale picture to a rectangular “pixel” of variable height. The resulting STL files could be run through the slicer to produce the necessary files to load into the printer. This was eventually replaced with a new Python script capable of converting images to native printer files through UVtools.

On the hardware side, all [Gabe] had to do was remove the vat that would usually hold the resin, and replace that with a wooden lid to both hold the UV-sensitized paper in place and protect the user’s eyes. [Gabe] says there’s still some room for improvement, but you wouldn’t know it by looking at some of the gorgeous prints he’s produced already.

No word yet on whether or not future versions of the project will support direct-to-potato imaging.

OpenSCAD has a lot of fans around these parts — if you’re unaware, it’s essentially a code-based way of designing 3D models. Instead of drawing them up in a CAD program, one writes a script that defines the required geometry. All that is made a little easier with the Belfry OpenSCAD Library (BOSL2).

BOSL2 has an extensive library of base shapes, advanced functions for manipulating models, and some really nifty tools for creating attachment points on parts and aligning components with one another. If that sounds handy for designing useful objects, you’re in for even more of a treat when you see their functions for gears, hinges, screws, and more.

There’s even one that covers bottle necks and caps. (Those are all standardized by the way, so it’s never been easier to interface to existing bottles or caps in a project.)

OpenSCAD really is very versatile software. It powers useful tools like this screw, washer, and nut generator as well as having more unusual applications like a procedural terrain generator. It’s free, so if you’ve never looked into it, check it out!