Functional 3D Prototype With Springs

I need a fully-working 3D printed prototype built primarily for functionality testing. At its core the design relies on a compression-spring mechanism, so the hard parts must be strong enough to take repeated load cycles and keep tight tolerances around the spring pocket and guides.

I did not lock myself into one specific filament yet—my answer was simply “need spring” because the key requirement is that the chosen material plays nicely with a metal compression spring and doesn’t crack or creep under stress. If you feel ABS, Nylon, Polycarbonate, or a comparable engineering resin is the smarter choice, let me know why; I’m open to data-driven suggestions.

What I will provide:
• Design, validation and documentation completed
• Performance targets for the spring travel and return force.

What I expect back:
• One physically printed prototype assembled with the compression spring installed and tested for smooth operation.
• A brief test note confirming the mechanism meets the travel and return criteria.

If minor tweaks are needed after the first print, include one revision in your quote. Experience designing snap-fit or spring-loaded parts for FDM/SLS is a plus because the ultimate goal is a robust, repeatable part rather than a one-off display model.