Securing lens/shutter to lens board

[Daniel Grenier]

I have two lenses in copal 3 shutters that I've mounted on home-made lens boards. The shutters do not have a locking pin like my newer copal 3s have and the lenses are, therefore, somewhat loose in the board and can rotate. Not a good thing! I'm looking for a good trick to "lock" the lenses/shutters in place. Any suggestions?

Thanks

[Frank Muscroft]

Daniel,

It may be that the threaded locking ring cannot tighten sufficeintly on the lens board because of a smaller than normal thickness. Have you tried buying or making a small spacer ring to place under the locking ring so that you can tighten the ring better onto the lens board?

[Ralph Barker]

I also make my own wooden lens boards, Daniel, and have encountered the same problem. If the face of the lensboard is particularly smooth, there's not much for the smooth rear of the shutter to grab onto unless the locking ring is really tight. Try slightly roughing up the face of the lensboard with 100 grit sandpaper, right around the hole, or try a very thin, flat rubber gasket.

[Ed Balko]

Expanding on Ralph's suggestion of a thin rubber gasket, an O-ring between the lensboard and the rear of the shutter has worked for me. These are available in a variety of thicknesses in most hardware stores -take the shutter with you to the store in order to find the correct size.