Spring Clip

I wanted to experiment with 3D printing an object with a built-in spring. This clip is designed so that when the clip is closed there is still some force from the spring holding it shut (as you would expect from a spring clip).

This is only a partial success: it works as expected, but if printed in ABS, the plastic will yield slightly when you open the clip, rather than being completely springy.

ABS is simply not a good material for making functional springs, as the yield strength is too l