Sachtler 18 tripod has no lock tilt

Question

Hi, I have a Sachtler 18 tripod that has worked great and served me well. Recently, though, I stripped a part and now I cannot lock the tilt function, so whenever I leave the camera it tilts all the way forward or back. Except for this everything works fine.Basically, the thing you s***w down to lock the up/down pan works by s******g the thumb turn thing on the outside into a small thing inside which tightens against a ring about two inches in diameter. The broken part is the thing the thumb turn thing screws into.I don't know if I can get just that part or if more of the assembly has to be replaced in tandem. I?d be happy to do it any way I can.Thanks in advance for your response,--Dan [e-mail]