210mm Sinaron-S cemented to Lens board

[Juergen Sattler]

Hi,

I have been trying to unscrew a 210mm Sinaron-S in a Copal 1 from the Sinar lensboard to use it on my Field Camera, but the retaining ring won't nudge. It says on the Sinar lensboard that the lens was mounted and adjusted by Sinar - would they cement the retaining ring to the shutter thread - that seems a little extreme.

Is there any way to take that shutter off that lensboard without damaging it? I did use a lens wrench, but as hard as I try - the retaining ring won't move.

Juergen

[Bob Salomon]

Unscrew the shutter from the ring and order a new retaining ring for a Copal 1 shutter.

Or is the shutter glued to the board?

[Gem Singer]

Hi Juergen,

It seems un-likely that they would use cement. More than likely, it's a case of an over-tightened retaining ring. Remove both elements of the lens, put them in a safe place. Only deal with the shutter. Take the shutter in one hand and the lens wrench (spanner wrench) in the other. Make certain that the lens wrench is engaging the notches in the retaining ring. Turn them counterclockwise, against each other, as hard as you can. If that doesn't work, devise a strap wrench with which to grasp the shutter and give you more leverage. If that doesn't work, let a professional tech. do the job.

[Kevin Crisp]

Before you crank on it, as above, open the aperture blades all the way and put the shutter blades on "T" so that there is no way you can damage them.

[Juergen Sattler]

Thanks to all of you. I managed to get the lens off the lensboard - the retaining ring was extremely tightened.

Juergen