Mounting Shanel-5A shutter

From advice I got in another thread (https://www.photrio.com/forum/threads/fujinar-barrel-lenses.161424/) I bought a Shanel-5A shutter to mount Fujinar lenses on a plate camera. I'm now stuck for a way to mount the shutter to a board. I've measured the threads to be about 62mm but I'd like to hear from someone who uses a retaining ring and who can tell me its exact size. I'd also welcome suggestions for an alternative (cheap?) way to mount the shutter to a 4mm wide wooden board with a 65mm hole.
Thanks.
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Nissin

If the rear male mounting thread is 62 mm the thread is likely the same as the threading used on the late-model Copal 3 shutter. The Copal 3 thread is 62 mm diameter x 0.75 mm pitch.

I’ve bought a number of these from Chinese maker/sellers on eBay. They’re made right, fit well, and get the job done. The standard retaining ring of a late-model Copal 3 includes a spacing collar for use on thin metal lens boards. Many users omit the spacer. It isn’t needed on a thicker wood lens board.

https://www.ebay.com/itm/Copal-Compur-Prontor-3-Shutter-Retaining-Ring-Schneider-Fujinon-Rodenstock-Lens/173052172938?hash=item284ab69a8a:g:SbIAAOSwUM5aKMZg&_sacat=0&_nkw=copal+3+retaining+ring&_from=R40&rt=nc&_trksid=m570.l1313

You’d also need a dedicated Copal 3 ring wrench. Here’s one for the Shen Hao Camera Company, so it should be properly made,

https://www.ebay.com/itm/Large-Format-Lens-Retaining-Ring-Spanner-Wrench-Removal-Repair-Tool-Copal-0-1-3/282812270700?hash=item41d8ecc86c:g:I6wAAOSwGzhaQ2dZ&_sacat=0&_nkw=copal+3+retaining+ring&_from=R40&rt=nc&_trksid=m570.l1313

You can also use a shutter-mounting flange. The flange is held to the front of the lens board with 4 ~ 6 screws. The shutter's rear threads screw into the flange.

Note: The following table makes clear that obsolete Copal 3 shutters used 60 mm x 0.75 mm threading.

Another caution: Users sometimes confuse the late-mode Copal 3 with the Copal 3s. The Copal 3s shutter uses 61 mm x 0.75 mm thread (used on the Fujinon 250 mm Soft-Focus lens, for example).

https://www.skgrimes.com/products/mounting-flanges

In the following table see ”Copal 567 #3 Compur#3 Prontor Professional #3”

This is the 62 mm diameter x 0.75 mm flange that fits the late-model Copal 3, and probably the Shanel 5A. You can email SK Grimes for that information. S.K. Grimes also supplies retaining rings.

https://www.skgrimes.com/products/mounting-flanges/metric-stock-flanges

You can also check with a machinist or auto mechanic in your area. He or she should have a micrometer to accurately measure the thread diameter and a set of metric thread-checking gages to verify the pitch.

For simple jobs like making a retaining ring https://www.srb-photographic.co.uk/ is a worthy competitor to skgrimes.

Thank you Ian & Dan for your advice. I went ahead and ordered a Copal 3 ring from the vendor in Hong Kong. I've done business with him before and it only takes a few days for goods to ship to Japan. Fingers crossed that the ring fits.
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Nissin

Update: I received the Copal 3 ring, but, unfortunately, it doesn't fit. It's too small by the width of the thread. I don't want to pay for a custom made ring, so I'll explore ways of using tape to pad the mount to fit the 65mm hole.
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Nissin