Letter 30062 Need process for piston rod Ry Value of 0.4 microns [India]   ++++ We have a typical problem of not being able to achieve 0.4 Microns Ry Max. on the Piston rods. The piston rods we use are Machined, Rough Ground, Semi Finish Ground and Finish Ground, Then Burnished, Hard Chrome Plated (Heef 25 with 600-800 Hv Hardness) Again Burnished and then Superfinished with 4 stones of 1000, 1000, 1200 and 1200 grades.With this process we can achieve 0.8 - 1.0 Microns Ry. the Ra value is well within the acceptable limits of 0.2 Ra Max. Please suggest some modifications in the process that can solve our problem. Thanks, Alok Sharma Engineering Manufacturer - Pune, Maharashtra, India Dear Reader: please choose what you want to do-- I want to answer or follow-up on this subject publicly (in non-commercial fashion).   I want to post a new question or inquiry of my own on a different subject.