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Darin Boville
25-Nov-2009, 18:52
O.K., here's a dumb question.

I just bought an odd, interesting lens with a flange. It's a process lens which has been mounted into a Copal shutter. It's the first lens I've owned that didn't have the regular retaining ring.

So how do I get this bad boy on the lens board? Screw it on using the screw holes (drilling holes in my board first, of course!)? Unscrew the flange in some way and use it like a regular retaining ring? Or...?

Funny, I searched the site and the internet and never really found an explanation...the answer must be terribly obvious...

--Darin

Oren Grad
25-Nov-2009, 19:30
Screw it on using the screw holes (drilling holes in my board first, of course!)?

Yup. :)

Darin Boville
25-Nov-2009, 19:35
Yup. :)

That's what I figured. Any certain kind of screws? Brass?

Off to the Buy and Sell board!

--Darin

Jim Ewins
25-Nov-2009, 20:20
Darin, I can't quite visualize your set up - could perhaps help if I see a sketch. I've machined lens boards for Speed Graphics and enlargers. Jim

rdenney
25-Nov-2009, 20:25
O.K., here's a dumb question.

I just bought an odd, interesting lens with a flange. It's a process lens which has been mounted into a Copal shutter. It's the first lens I've owned that didn't have the regular retaining ring.

So how do I get this bad boy on the lens board? Screw it on using the screw holes (drilling holes in my board first, of course!)? Unscrew the flange in some way and use it like a regular retaining ring? Or...?

Funny, I searched the site and the internet and never really found an explanation...the answer must be terribly obvious...

--Darin

With a metal lens board, the threads often come through far enough to use the flange as a retaining ring. You use the screw holes to tighten it using the spanner. I would be embarrassed to have done it except that the suggestion was made to me by Grimes.

If I was going to screw it in, I would take the flange down to a hobby store that sells bits for building radio-controlled airplanes and cars. They will have a good assortment of 2-56 and 4-40 screws, and they will also have a tap and drill. I would drill the holes, tap them for those screws, and then screw them down, using the screws that fit in the flange.

With a wood lens board, I would use fine brass wood screws after carefully (with a bit in a pin block, not a power drill) drill pilot holes.

Rick "currently using a Ilex #4 flange as a retainer on a Sinar board" Denney

Bruce A Cahn
25-Nov-2009, 20:33
If the lens is heavy you can mount it more safely with nuts and bolts.

Darin Boville
25-Nov-2009, 20:34
O.K., I might need your help to walk me through this--I'll shoot a few photos and will post them here later tonight or tomorrow.

Thanks!

--Darin