Spacers for tighter fitting of copal shutters?

[walter23]

I took my shenhao out into some fairly cold temperatures yesterday and the stupid lens became so loose in the lens board that I couldn't really use it effectively (differential contraction of the materials in the cold, I guess). The retaining ring is already tightened pretty much to the maximum, so I was wondering if there's a source of spacers to give a bit more effective thickness of the lens board, so I could tighten it more than it already is? I'd like to avoid a repeat of this.

[Claude Sapp]

I have dealt with the same by putting an o-ring from the hardware store between the shutter and lensboard.

[Capocheny]

Two of my lenses are mounted out a little bit further from the lens board via spacers that the tech installed. He cut these out of aluminum... but the 0-rings that Claude suggested will work as well if not better.

One advantage to having a spacer on the front is that the aperture scale indicator is a bit more accessible for adjustment.

Cheers

[walter23]

I guess I'll check the hardware store. The only one close by is a Home Depot and in my experience they have a pretty limited selection of these kinds of things - all their stuff seems to be intercompatible, meaning you could build your whole house out of Home Depot stuff, but if you happen to have something else you need to find a fit for.... good luck to you ;)

That's why I was hoping there was a "copal 0 spacer" I could buy somewhere.. ahh well. I'll look around the city.

[Alan Davenport]

Another way, similar to the O-ring but more solid, is to use a piece of electronic solder. Just cut a piece a bit longer than the circumference of the hole it must fit in, then fit the solder around the hole and cut it off to make a complete circle (no you don't heat it.)

Solder is about 60% lead and 40% tin, so it will deform a little when you tighten things down, and everything ends up nice and tight. Make sure you use rosin core solder so there's no danger of corrosion. Solder that is used for plumbing and sheet metal work typically has an acid flux core, and isn't recommended even though you won't be melting it and releasing the flux.

[Sal Santamaura]

Maybe we all shouldn't have removed and discarded those little anti-rotation screws...

[walter23]

Another way, similar to the O-ring but more solid, is to use a piece of electronic solder. Just cut a piece a bit longer than the circumference of the hole it must fit in, then fit the solder around the hole and cut it off to make a complete circle (no you don't heat it.)

Solder is about 60% lead and 40% tin, so it will deform a little when you tighten things down, and everything ends up nice and tight. Make sure you use rosin core solder so there's no danger of corrosion. Solder that is used for plumbing and sheet metal work typically has an acid flux core, and isn't recommended even though you won't be melting it and releasing the flux.

I like that idea. I'll see if I can find any solid solder though; I don't like the idea of rosin being pushed out.

[Jim Noel]

Try your local AUto SUpply store for "O" rings. NAPA dealers usually have a very good assortment.

[Capocheny]

Try your local AUto SUpply store for "O" rings. NAPA dealers usually have a very good assortment.

Or, look up "Gaskets" or "Rubber Gaskets" in the Yellow Pages.

Cheers

[Alan Davenport]

I like that idea. I'll see if I can find any solid solder though; I don't like the idea of rosin being pushed out.

I've never seen any solder where the rosin was liquid, so it isn't really a possiblilty. I just mentioned the acid/rosin flux thing as a sort of "standard disclaimer."