Very tight speed setting ring on Schneider 72mm XL - presumably not normal?

[newmoon2night]

I've just bought a used Schneider SA 72mm XL with Copal shutter.
Bought mail order from a dealer and have a couple of days to decide whether to keep or not.
The aperture setting ring works fine, shutter release works fine, but when I come to change the shutter speed setting the ring won't budge.
The only way I can change the shutter speed is to untighten the front element slightly. Then of course the front element is loose!
Has anyone any idea what is causing this?
The front element doesn't have to be overly tight to jam the shutter speed setting - probably tight like you'd tighten the plastic lid on a milk bottle.
Apart from that the lens looks spotless; it's about ten years old with the smooth action aperture setting ring.
Any advice appreciated. Thanks.

[jb7]

Have you removed the small grub screw to the rear before mounting the lens?

Other than that, I don't know-

[newmoon2night]

Have you removed the small grub screw to the rear before mounting the lens?

Other than that, I don't know-

I haven't actually mounted the lens on a lens board yet - could that be the problem?
I wouldn't have thought it would make a difference as the lens board would go the other side of the shutter unit. I've had a look and the screw isn't present anyway.
As far as I can see it seems to be that the back of the front lens unit tightens on the shutter ring. I wonder whether there is supposed to be a spacer there or something?

[jb7]

I don't think that's the problem, since it's the outer ring that rotates-

[percepts]

there are usually very fine spacer rings that come with a new lens. These are used to very fine tune the front and back element spacing by the manufacturer. It maybe yours is missing but the lens should never be overtightened anyway. The thickness of the spacer rings depends on each individual lens as far as I'm aware. Not as important for symmar type designs. i.e. if they are missing or slightly wrong thickness the effect is minimal on symmar designs but can be siginificant for some lens designs.

However, I have that lens in copal 0 and the front element does not come anywhere near the shutter ring. It would not touch the shutter ring if the spacer was missing so I don't see how that would cause a problem unless the copal shutter was an older design which is different to mine.

Having said that, it seems tightening the lens is causing the problem so it sounds like there is a fault. You have three options. Send it back, get it serviced or buy a new shutter. The third option means you may also need to send to Schneider who will fit new shutter with correct spacers. The second option may or may not get you the correct spacers if they can fix it. The first option will get rid of what you should not have been sent in the first place. I'd opt for sending it back and telling them to sort it out at their cost and not yours.

[ic-racer]

Some black copal shutters have a 'trim ring' around the base where the lens mounts. If it is binding here then the lens probably was in another shutter originally. Try mounting the lens without the ring and see if it still binds. You can also check the overal lens dimension from the spec sheet. 81.5mm I believe.

I don't think lens spacers are the problem here.

This picture shows a copal shutter with the trim ring removed to allow a larger lens to fit. (Note the area circled in red where the ring would have been).

[jb7]

My 72mm definitely doesn't have an extra ring,
and fills all the space in the area marked in red-

[newmoon2night]

I couldn't fathom it out, and the lens doesn't actually touch the shutter speed ring, but it was definitely the tightening and loosening of the lens that made the difference.
Anyway I've opted to send the lens back and got it in this morning's post so it gets back on Monday.

[Mike1234]

I think you're doing the right thing in sending it back... something is definitely awry. It might be a cheap easy fix for one with experience but a "competant" technician will not be cheap.