Almost finished my DIY skimmer neck cleaner (the swabbie idea came from FishOfHex on YouTube, I just designed a housing for it). Total cost is around $20 AUD for the motor, power supply, filament, knitting mesh and electrical connections etc.
A photo of the motor inside the housing. Other parts are in the background.
Photo of the knitting mesh that will be glued on the sides to actually scrape off the skimmer scum.
Photo of the assembled piece (minus the knitting mesh) after I finished the wiring inside the housing.
And a very quick video of the swabbie spinning. The motor in the video sounds quite loud because this was filmed inside my 3D printer enclosure, it actually only makes a very soft hum.
I've still got a little bit to do (I might re-print the part that spins inside the neck and make it thinner) and then I need to get it on the skimmer. Once it's all finished I will upload the STL to Thingiverse