I am trying to achieve low friction linear motion as economical as possible because this will be a mass produced part. Picture a 1/2" diameter aluminum rod that needs to slide about 9" through a low friction bushing (bushing about 1.5" L). There will be around 90 pound/inch radial torque moment on the bushing from the rod but still need linear slide. I have checked into linear bearings and Frelon bearings but the cost is prohibitive. What are my best material/product options for low friction economical solution (lubrication not possible)? BTW, the rod could be stainless steel or some other material??