Originally Posted by RcOldskool

My coworker is a New Design Engineer and CNC programmer for our huge CNC's. We did a Solidworks FEA Stress analysis on the B5M chassis to see how we can remove weight without affecting rigidity. The "spiderweb" design is used to retain its "factory" stiffness indicated in dark blue in the first pic below. The lighter shades are somewhat weaker areas. Without the spiderwebs we started to see green to yellow areas which noticeably have more flex under load so in order to reduce weight and keep it within light blue to dark, we had to add the ribs. We weren't concerned about the lighter shades not dark blue because once the plastic parts were assembled and installed, the chassis was re-enforced to no flex at all. The last pic is the final product with plastic frames attached. Mill time is 39 minutes a chassis at .073" depth. Factory mill is .050". Chassis is .105" total so there's .032" left at bottom of mill holes. Effective weight loss of 30 grams on the money and still stiff as stock. The power of solidworks at its best when used to its potential.