Hi! I purchased a Wilson 3OUR0-20 Rockwell tester yesterday. It came from a knife maker who had gotten out of knife making. When loading the minor load the gauge is very jerky and stiff and the capstan wheel nut does not adjust smoothly at all. It seems like the lift penetrator is maybe a little seized up? It is so jerky that the gauge jumps all over the place. Does anyone have advise on how to make it operate smoothly? Thanks!