Recently I saw you can buy heatshrink tubing cartridges for Dymo label makers. This would be really convenient to make professional looking markers to identify individual wires and cables in some of my larger projects. (Cable and wire markers for industrial applications such as these have been around for at least a decade now, but are pretty expensive. This solution from Dymo seems to be somewhat more mainstream, but it still is too expensive for the hacker)
However, my hopes were dashed when I realised that the cartridges aren’t compatible with my $35 Dymo LetraTag. Also, each cartridge is $50, so I wasn’t keen on buying one hoping that I could get it to work with my label marker.
So I got thinking about making my own and I managed to cobble together a somewhat effective method using some regular heat shrink and some 180 grit wet & dry sandpaper.
New Scientist recently detailed the construction materials for the simplest flex sensor I’ve ever heard of – a graphite pencil and a piece of paper. It is obvious when you think about it, but as New Scientist details in in their article Pencil lines as sensors, 21st March 2015 (No 3013) edition,
“MacGyver would be proud. Drawing a rectangle on a piece of paper with an ordinary pencil can create a sensor.”
Following on from the recent teardown of a cheap energy meter, I thought there might be some potential to hack this device. Well the EOUT “pulse output” pin shows some promise. The chip’s datasheet says that the EOUT pin outputs a pulse for each unit of energy the meter measures. Additionally, this function is enabled by default.
Since this is enabled, by default, I made some mods to the case and soldered 3x wires directly to the chip.
Wires soldered directly to chip pin 21 (EOUT) and power supply (decoupling capacitor)