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.
- A cheap thermal label maker. Probably don’t try this on an expensive printer.
- Coloured heat shrink. The technique works with black heat shrink, but it is really difficult to see.
- Sandpaper. I found that 180grit wet & dry sandpaper worked well.
Using the sandpaper, roughen up one side of the heat shrink. Doing this improves the lettering contrast.
Next, insert the heat shrink in the printer with the rough surface touching the print head. Make sure any excess length of heatshrink is contained within the printer to allow the label maker’s cover to be closed. Closing the cover engages the print head against the heat shrink and drive wheel.
Type in you message, noting that larger fonts tend to work better and press print.
The results are difficult to photograph accurately, but a close up shows the result.
Finally, slip the heatshrink over the cable and apply heat to shrink. Take care to avoid heating the region where the text was printed because it blurs out.
The final result is a bit difficult to see in the photo but the final result is adequate where a cheap but durable cable marker is required.