My McMaster ballnuts were doing the same thing under load, but I noticed that rolled THK screws with similar accuracies were not doing this at all. Part of this just points to the THK's as an awesome design, but I also noticed that the THK's use lots and lots of grease. Why don't the rolled ones from other manufacturers do that. Do you think it would help if we pt grease on the screws. I put lightweight oil on mine, but that just reduces friction, it is not preserving the balls. |