I was tired of the Smartphone holders that you glue on the back of your Smartphone Case and that will break after a short time.
So I made one myself, since I printed my Smartphone Case anyway, I thought I can slightly modify it and insert a Knob with a mechanical connection. You have to subtract the model from the smartphone case model in an editing software of your choice and then print both separately. So you have the key for the knob to fit in(maybe the photos explain it better). The advantage is that you can adapt the knob to your personal needs (Size and position).
The knob can be printed without Supports and could be fitted in the case in three positions.
I would recommend printing this one in a flexible filament. FIBERFLEX 40D worked quite well for me.
Going to make more designs with the same key on the bottom so you can easily switch them as needed.
The author remixed this model.