nice old lock. when i got this lock it was compleately bound up and sat for many years. was quite the project just taking it all compleately apart and had no key. got it all cleaned up and reasembeled. took the cylinder to a top notch lock smith and he made a key for 45.00   then i reasembled it.problem.would not work probably. so i took it apart. what you see in photo there is a square shaft that runs from one knob to the other. that was missing.so me being a ex machinest had to make one.on one end had to bake a bushing with square to round to fit. quite the project but i got it perfect and to the proper length. lock seemsed to work great. even with key works nice. problem is there is no way to remove key and have the door locked.turning key doed release the latch same as turning either knob withoutkey. i am not a locksmith just a jack of all trades. i have tried changes the timing etc. i cant see why it wont actuall lock dood.i am 80 and just givein up on it. so new owner can figure it out or just display it. it weight 6 lb. its a machinical work of art.    this door set is complete and nothing missing.i am not a lock smith. was a machinests and jack of all trades. should be a good chalenge for a real lock smith.