I make it a practice to remove the flint lock off a gun every time I clean it. And If it's fired even once it gets cleaned. Rarely is there any fouling to speak of inside the lock but I still wipe it and lube it. On percussion guns I don't remove the lock with every cleaning, just periodically. I also do not remove pinned barrels unless the gun gets wet or otherwise when work needs to be done or once every year or two.