I have a Wollensak 15" f/5.6 lens in a Alphax Synchro shutter. There is no mounting ring or flange. I have Klge-mounted it to a board with duct tape for now.

SK Grimes quotes over $65 for a replacement ring. Don't want to do that. Can't quite find the spec for the mounting ring thread size. I'd like to find a hardware store level solution or something from a machinist's supply source.


So the question is: What is the ring size and thread spec for this shutter?