I just recently (during the summer) had my parents buy me a new king trombone with F attachment and the trombone specialist guy at the place said you need to oil the rotor also. So I was wondering if anyone happens to know how often i should oil it. Right now i've only been doing it like one every week or two. kinda just depends on how fast i can push it right now. Also I was wondering if you know any good oils for the rotors or if that doesn't really matter as much as like slide oil/cream does. thanks