Working with a sliding system for a pull out rack and here's a problem I started thinking about. [PLAIN]http://img168.imageshack.us/img168/8418/rollers.png [Broken] Sorry for the awful picture, it's extremely basic, but hopefully enough to get my point across. The picture shows two SS pieces (304 or 430, can't remember...) in silver. The drawing is facing them dead-on, so they run along the plane you're looking. The rollers are pressed between them, angled, and are Delrin plastic. The rollers allow the members to slide (obviously ) along each other. My question is, if a downward force is applied to the top steel member, after many, many times of sliding the two members back and forth, over and over, the rollers will start to wear. But will they wear uniformly along their sides, or will they wear more in the bottom inside / top outside corners due to them being on an angle? I've been pondering this, trying logic, since I'm not exactly sure how to go about calculating out this mess... Perhaps I need to drag out the ol' Dynamics book. Any ideas or suggestions or thoughts are appreciated and welcome. Thanks!