Since the rubber rings of my generic steel doorstoppers are old and brittle. One of those just broke off, i designed a replacement to repair it.
In the process i took the chance to model the entire thing including the rubber foot because this also does not look that good anymore - since it is easy to model, i did the whole thing, so it can be printed/machined if someone wishes to
The model is fully parametric (Fusion 360 file is included)
i printed the ring and foot with TPU Shore 95A from Geeetech (Affiliate Link) - printed with 3 perimeters and 25 % gyroid-infill it behaves almost the same like the old solid EPDM rubber
be aware that i only used this to replace the ring and the foot part so far and not have tried printing the core - if you print the core, i'd suggest printing it upright and pausing it higher before the curve starts, then fill it with sand or steel balls and resume the print
The author marked this model as their own original creation.