Copal 1 Lens Board Hole Size

[eurekaiv]

I recently acquired a 210mm Schneider lens in a Copal 1 shutter without a lens board. I picked up a Linhoff style Copal 1 board on eBay but the hole seems excessively large compared to the shutter's threaded diameter. I didn't measure but there's probably 1.5mm of play all the way around and this seems like far more slop than there ought to be. I was able to get it tightened down and centered (well enough) but I have no context for how it should be as I've only one other lens for my 4x5 that's never been removed from it's board.

 

[Dustin McAmera]

What should fit closely in the lensboard hole isn't the lens barrel, but a shoulder of the tightening ring.
You can see a retaining ring at Grimes; see the narrow shoulder sticking out? That should fit in the hole, so your 1mm+ clearance round the lens barrel itself is right.

https://skgrimes.com/product/retaining-ring-copal-1/

 

[Dustin McAmera]

I should admit that, before I knew this, I have made a couple of holes in lensboards for myself, and sized them to fit the lens-barrel, and the sky didn't fall on me, so I haven't gone back and corrected them.

 

[eurekaiv]

Ahhh... so the ring was wound on backwards and I repeated this error. Thanks!