Bob, Both my K2 and K3's tuning knobs are the proverbial ":smooth as silk". Could yours have peen pushed against the front panel excessively hard as the set screws were tightened? It's a "tricky" operation and might require several attempts to get it "just right".. It's not important to the matter at hand, but the shaft turns an encoder, not a PTO. 73! Ken - K0PP