The attached pic shows the altitude/latitude adjustment screw and casting. Even being unfamiliar with this mount the problem was obvious. I took the part off and it appeared to be cracked. The area around the threaded hole broke off when I tried to straighten it enough for the wing nut to clear the base. I have seen mentioned that this is a weak point on these mounts, someone mentioned rigging a solution when theirs broke. Does anyone know a source for this part, or could they explain how to best work around it? There seems to be some creep when I just tighten things to hold - I also worry I'm just overstressing another part and maybe causing another break of some sort.
Is the chain at the feet original? I don't see it in other photos here. Maybe just on the taller refractor legs?