Update (Dec 2021): If you access to a 3D printer, I would now recommend this solution, which makes it super easy to replace the trimmer line. I have been using it for a few months now with zero issue.
An update on using ordinary trimmer line for the Ozito battery trimmer. I finally found a super easy and robust way to do so. No need for any 3D-printed adaptor, which is simply not strong enough to withstand the amount of force we are dealing with. You should be able to start immediately with common tools that you already have.
These are all the material/tools you need:
- 2.4mm trimmer line
- 0.75mm wire (just use any thin wire you have lying around)
- flat nose plier
- cutter (or scissors, to cut the trimmer line)
PS: I have also tried using zip ties and found them to be unsuitable. 1) Trimmer lines are made with composite nylon, which makes them stronger and more resistant to abrasion. Zip ties simply don't have that kind of strength. 2) Thicker zip ties have about 5mm thickness, which does not fit into the blade holder. The thinner zip ties (eg. 2.5mm thickness) are simply to wimpy to be used for the task.