I am working in a project to design a machine to press in bearing into a part with tolerance ring. IPA (Isopropyl Alcohol) is requested to apply on the tolerance ring before press in the bearing to reduce the hard particle created during the process. However, the machine is jerking during the process. The bearing cannot be press in smoothly and causing our production reject due to the bearing height after press in cannot control properly. This jerking only happen if IPA is applied. So is this due to the IPA chemical properties problem? Or my machine design problem? My machine design is using servo motor to drive the ball screw. Pressing force is about 50 to 100kgf. Hopefully someone can help me to solve this problem. Let me know if you need more details. Thank you.