I have animated a spring contracting and expanding by creating a set of expressions/controllers. The pictures show my current progress. What I need to do now is set the spring up so that the first two coils and the last two coils stay together, while the remaining coils stretch appropriately. If I remember correctly, I…
Ah - I think you're overthinking it. I would go the easy route and just attach endcap geometry that are just bound to the dummies. Just nudge them so they lineup with the springs.