Two clothespin hacks mentioned in the article, side-by-side.

Need To Probe Circuits? Remember About Clothespins!

After browsing Thingiverse for some printable PCB probe designs, [Henry York] looked around and found a wooden clothespin on his desk. After some collaboration between his 3D printer and his CNC, Henry graced us with a nifty helper tool design that many of us might want to make in a pinch – a small, cheap and easy to make PCB probe, for circuits where soldering and headers are out of the question. Small magnets are glued to the clothespin, holding it flush to a magnetizable work surface (aka a toaster tray), and the probing itself is done by an extruder cleaning needle end. 3D printer and Edge.Cuts files are shared with us – thanks to Henry’s helpfulness, it should be easy to repeat if ever needed!

[Tyler Rosonke] (@zonksec) was programming a batch of badges and needed a reliable way to attach to a 6-pin ISP header – without actually soldering to the badges before they’re handed out to participants! A clothespin materialized nearby yet again – most likely, channeled from a different dimension by the spirit of numerous acrylic-cast pogopin-toothed clip-on tools we scroll by on Aliexpress. With a small perfboard piece and a bunch of pogopins jumping out of their respective drawers, it became no longer necessary to hold a bundle of male-ended pin header wires at a weird angle while nervously looking at the avrdude progress bar. This ended up saving a whole lot of time, something that’s always best spent on adding insidious bugs to the badge firmware (as well as, perhaps, easter eggs).

We’d love to hear about all the small hacks and improvements that you, hackers in our audience, invent. Whether it’s reusing a SOIC flashing clip for ISP programming or printing yourself an octopus-like contraption with needle probes, you should share it with us!

SOICbite: A Program/Debug Connector For An SOIC Test Clip

The problem is well-known: programming and debug headers consume valuable board space and the connectors cost money. Especially troublesome are the ubiquitous 100-mil pin headers, not because they’re expensive, but because they’re huge, especially along the z-axis. If you’re building miniature devices, these things can take up a ridiculous amount of space. With some clever thinking, [Simon Merrett] has found a way to re-use something many of us already have — an SOIC-8 test clip — to connect to a special footprint on the PCB without requiring another connector. He calls the system SOICbite.

The SOIC clip attaches to a footprint consisting of eight pads, four on each side of the PCB, plus five non-plated-through holes, which serve to anchor the clip in place. The idea of mating a PCB footprint directly with a removable connector isn’t entirely new — Tag Connect has been doing this for a while, but the connectors are expensive and single-sourced. On the other hand, SOIC test clips of varying quality are available from a number of vendors, including dirt-cheap deals on your favorite websites. The one disadvantage we can see is that the SOICbite footprint must be at the edge of the PCB to properly mate with the clip. The savings in space and cost may well make up for this, however.

[Simon] has made his KiCAD footprint available in a GitHub repo, and has offered to host footprints for any other CAD package there as well. So, fire up your preferred tool and draw one up for him to get these things widely adopted, because we think this is a great idea.

For the commercial alternative, check out our coverage of Tag Connect back in 2014.

 

Improved Digital Caliper Interfacing, Including 3D Printed Connector

[MakinStuff] wrote in to let us know about a project he did for new and improved interfacing to the ubiquitous cheap Chinese digital calipers. Interfacing to this common caliper model is well-trod ground, but his project puts everything about interfacing and reading the data in one place along with some improvements: a 3D printed connector that makes mating to the pads much more stable and reliable, 3d-printed-plug-for-digital-calipersa simple interface circuit for translating the logic levels, and an interrupt-driven sample Arduino sketch to read the data. Making the sketch interrupt-driven means the Arduino never sits and waits for input from the calipers, making it easier have the Arduino do other meaningful work at the same time, ultimately making it easier to incorporate into other projects.

The connector has spaces to insert bare wires to use as contacts for the exposed pads inside the calipers. Add a little hot glue and heat shrink, and you’ll never have to fiddle with a hacked-together connection again.

This common caliper model has been hacked and re-purposed in interesting ways. We’ve seen them used as a Digital Read Out (DRO) on a lathe as well as being given the ability to wirelessly log their data over Bluetooth.

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