advice on Cooke with stuck Soft focus

[Emil Schildt]

I remember talking to Adam Dau about a Cooke he had on the bench. The mechanism was stuck. They managed to unstick it, but it took very careful and powerful incremental force. This is not a Do-it-yourself job.... that would be a major mistake. Get it fixed properly or sell it.

you're proberly right, but there is a third option: just to keep it, and use it as a normal big lense...

[Ole Tjugen]

Forsøk å spørge Cooke. Det kunne jo være at de tar det som en utfordring?

[Steve Hamley]

Gene,

Yes I knew he was in Europe. You can send and import for repair without duty.

But his location doesn't change the available options really. Shipping both ways is still a small faction of what a working lens is worth. But if he wants to bail, I'm interested at an appropriate price, and will pay his shipping!

Cheers,

Steve

[jnantz]

If you still want to use it before sending it off Saran Wrap and a rubber band to hold it tight makes a very nice soft focus attachment.

you are correct!

[Jim Galli]

Hi Emil.

No I don't have an early one like that. I would do this before give up;

Remove the front and the back glass but leave the center one alone. The helical inside would hopefully then be seen. I use a product made for cleaning the rubber for tyre repair. It is a liquid called Rubber Buffer. This stuff is tri chloro-ethylene. It leaves no residue and doesn't harm non metal parts if there are some. I have had some luck by soaking then working then soaking then working until finally things begin to move. You need a good vise so you can get some serious torque on the ring. I squirt the stuff outside and inside, any place 2 metals come together in the mechanism. It will start to "wick" the century of dirt out from underneath. Cooke was famous for their tolerance in machining. Everything is almost zero tolerance, no slop to work with at all.

I hope that helps. I use this stuff for sticky shutters too. Good stuff. Probably kills a few brain cells. You and me got none to spare.

[Emil Schildt]

If you still want to use it before sending it off Saran Wrap and a rubber band to hold it tight makes a very nice soft focus attachment.

Proberly.

If I only knew what "saran wrap" is....

[Jim Galli]

Don't put the saran wrap on the lens. For your style wrap up the model instead.

[venchka]

Proberly.

If I only knew what "saran wrap" is....

Clear, clinging, plastic film used to cover left overs in the 'fridge or fix old Cooke lenses.

[goamules]

I'd like to add two other possible helpers to Jim's good advise.

If you find his substance doesn't work, I've had luck with CLP Break-free. http://www.break-free.com/?location=/global/sitemap.asp

Also, when I want to get a stronger torque than can be applied with my hand and a rubber grippy material (like the back of a mouse pad), I make a tool out of a couple of pieces of wood, such as 1x4, about 3 feet long. Cut a semi circle in each board, about 1 foot from the end, that is slightly larger than the barrel you need to unscrew. Line with rubber grip material. Wire the ends near the cuts together. Grip the barrel in the cuts, and squeeze the other ends (non-wired). Of course, you may need two sets, or a vice.

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[Emil Schildt]

Don't put the saran wrap on the lens. For your style wrap up the model instead.

like this?