Retaining threads for lens boards......what to do?

[Rob_5070]

have a few anastigmat lenses which require retaining threads to mount on lensboards.

It seems like most people in the States take theirs to SK Grimes.

I've tried disasembling circular filters for the front filter thread/retainer - everything from 58mm to 67mm filter. The material just isn't strong enough and I've yet to find a perfect fit.

Any alternative DIY suggestions?

[Bob Salomon]

What size do you need and what thread pitch?

[Nick_3536]

Glue? Duct tape? If those are US or UK lenses then figure the retaining ring use imperial threads not metric.

[Neal Shields]

There are huge iris looking thingies that I have seen, (and have one), that people used to mount lenses.

You basically have a universal lens board. I see them on the auction site once and a while.

I have never used mine (it was part of an old lens test bench) because it doesn't look very substantual to me.

Mine has a locking screw and presumably you open the iris, insert the back element, close the iris, and lock the screw.

Has anyone ever used one?

[Neal Shields]

Every now and again I can find an old piece of camera equipment when I look for it.


http://truckgenerator.com/subdomain/sueandneal/cpgortz.jpg (http://truckgenerator.com/subdomain/sueandneal/cpgortz.jpg)

[Dan Fromm]

Rob, discuss y'r needs with Equinox Photo http://www.equinoxphotographic.com/index.htm (http://www.equinoxphotographic.com/index.htm)

Neal, back in the days when it was possible to go to a camera show on Sunday, buy odds and ends and list them on eBay that evening, and have enough profit to pay for going to the show within a week after that I bought and sold one. But I never tried to use it, my cameras are all too small.

Cheers,

Dan

[Darin Cozine]

I've used a rubber band to retain a lens/shutter on a lensboard before. But im a bit confused by your statement regarding disassembling filters. I take it you actually need something with outside threads so as to keep the glass in the barrel. You might want to look for a thin step-down ring.

[Paul Fitzgerald]

Hi there,

If you make your own lens boards, you can make the center hole an interference fit for the threads. Most lenses have a flange built into the rear of the barrel. You can find hard plastic curved washers at a hardware/plumbing supply store that can be used with screws against the flange. The washers will offset the screws enough to not touch the barrel, #2 size is large enough. If you like the look from the lens have a flange ring made.

Just a thought

[Rob_5070]

Bob - I really can't tell. Somewhere between 63 and 65mm and a pitch of at least 1.0 (I don't have a pair of calipers to be precise) and 46-48mm for the second one. If there was a shop which sold remaindered threads, I'd happily sit through and work out which one's I needed. The lensboard is bigger than a Copal 3 with no retainer ring.

I didn't pay a lot for these lenses so I don't really figure I'd do myself any favours getting a new threading ring sized up. And the lens hasn't any name on it other than anastigmat and weighs 800grams - that's a big rubber band.

I don't even know if they work, so I was just going to use heat-sink compoound/thermodynamic paste.

Could I use to this to bond the lens permanently to the lensboard? If it cracks, I'm not going to tell anyone I did it.

Possibly metal filler to seal the lens in?

Guess I'm just surprised that people actually 'succeed' in getting a retaining screw for such ancient anastigmats......

[John D Gerndt]

Here is and interesting idea (at least to me): ever hear of J B Weld? IF there was a way to coat the threads so that this mighty material did NOT weld to the male threads then one would have made a ring with the right female threads. I don't suppose Tefflon spray would work...does anyone know of something that does?

Cheers,

[John Kasaian]

Why not make a giant timmerman speed nut to fit your lens thread? You'd need a piece of springy sheet metal, or epoxy/spotweld bits of spring steel to a large washer or escutcheon. Sounds like a fun challenge.

[Jim Galli]

OK you've forced me to reveal my true nature. When I have this dilemmer I've been know to cut a fairly tight hole for the threads to drop into with a relief on the verso. I fill that relief in with hot glue which oozes into the threads and the releif and makes a nice tight fit. Never had a failure. Never admitted to doing such an awful thing. When you're tired of that lens and want to put it on Ebay the hot glue peals out in big chunks and no one's the wiser. My name Jose Jimenez.

[Doug_3727]

Rob,
Bite the bullet and send it to Grimes. They will select the right size retaining ring or flange that you need and send it back to you. Not very expensive and makes your lens mounting alot easier.
Good Luck,

[Bob Salomon]

Here are the jam nuts and flanges that we usually have in stock.

RODENSTOCK JAM NUTS
M 25 X 0.5 MM
M 32.5 X 0.5 MM (0 SHUTTER)
M 39 X 0.75 MM (1 SHUTTER)
M 39 X 1/26 MM LEICA THREAD (METAL)
M 39 X 1/26 MM LEICA THREAD (PLASTIC)
M 50 X 0.75 MM
M 62 X 0.75 MM (3 SHUTTER)
RODENSTOCK LENS FLANGES
M 26.5 X 0.5 MM
M 32.5 X 0.5 MM (0 SHUTTER)
M 39 X 1/26 MM LEICA THREAD
M 50 X 0.75 MM
M 53 X 0.75 MM

M 58 X 0.75 MM
M 60 X 0.75 MM
M 72 X 1 MM
M 90 X 1 MM
M 110 X 1 MM

M 120 X 1 MM
M 135 X 1 MM
M 145 X 1 MM
M 162 X 1 MM

[Bob Salomon]

J.B, Weld is simply a good epoxy adhesive.