HELP!!! MY Grandagon 90/4.5 stuck on the shutter!!!

[byuddy]

Is the retaining out of round?

[MikeHamilton]

I just bought a pair of spanner wrenches from Edmond Optics: edmondoptics.com. They are adjustable for most all lens sizes, come as 2 items for both pin and slot retaining rings and cost $39.00 Item NT36-413 in the Edmond catalogue. It is a handy tool for all camera and darkroom lenses mounted on lens boards. Good luck.