I have never checked a Leicaflex and was trying to remove the baseplate, I removed 2 screws but it still stays fast near to the tripod socket. This is the old series leicaflex. Don
You need a #3 Allen driver to loosen the nut that holds in place the tripod screw. In the bottom of the tripod screw you can see a square hollow where the driver fits. You turn clockwise since what you are unscrewing is the female part (attached to the camera) off the male threads of the outside of the tripod socket.
Thankyou Nikos: That was the answer, I guess Leitz didn't want just anyone to service their cameras. I was able to check and clean everything on the bottom, next is to see why the mirror sticks up only on 1/2000 sec. Thanks again .Don
