Hello, I am new to this forum and to the trumpet. I just bought a Holton T602 on ebay, which actually play pretty well! I know that I have to keep the valve well oiled, but when I put oil in the second piston, it often comme back slowly due to some kind of friction when I make a good pressure on it. If I take out the piston than clean it with a cloth than put it back, it move freely. My question is that : If I clean it after having oiled it and then put it back, can I damage the piston?? Am i better to keep it well oiled but with more (apparently) frinction??? Thanks for your help!!