To solve this, I made an improved wiper that uses a 3d-printed spring to hold the pad at a more constant tension. It holds the same felt wipers, just inserted sideways. It should also work with scotchbrite pads. Also I've only tested this on a Mini v1, but I think it should work on other printers too.
https://www.thingiverse.com/thing:3082324
I'd be interested in feedback on how it works. In particular, there are a couple of ways it could still be improved:
- More spring travel - this would require the felt pad to be taped down, as otherwise it will fall off when the spring is fully extended.
- Preload - Gives effectively more travel (and therefore more constant force) while still keeping height low. Would make installation slightly harder.
- One piece - not sure how to design this but I think it could be done.