Schneider Componon-S 150mm I recently aquired was on a Beseler lens board. The lens was too pretty not to play with so I took it off the lens board. Long story short I reassembled the lens' rear element without the lens board and now the whole thing is jammed up. I can't get it loose! I won't be printing 4x5 for a while but it bothers me that its not right. It appears that there are still threads that would allow it to be mounted with a jam nut, but the opening on the lens board is to small to accept the lens. Signed, A big kid who can't resist playing with his new toys.