How to disassemble a lens

[Chris Douglas]

I have a couple of Kodak Cine model b cameras I still use for taking 16mm movies. I have had no problem cleaning and lubricating the entire camera, except the lenses. There is dirt between the elements, and the focus is stiff to turn. I don't see any obvious way they disassemble, any hints? Thanks.

Chris

 

[John Koehrer]

If the lens has spanner slots/holes on the front ring 180 degrees apart you should be able to pull the front group out.
Taking it apart more completely should be the same basic method. IE: more spanner rings.

If you need to pull inner elements mark 'em and keep 'em in order unless you like interesting effects lioke
not being able to get a sharp image or funky flaring.

 

[David Lyga]

And, while you are at it, clean the helicoid by flushing it with lighter fluid while using a brush. When fully clean and dry, put a very light coating of petroleum jelly on the helicoid. You will experience much smoother focusing. - David Lyga

 

[jochen]

Hello,
instead of petroleum jelly it is better to use a soft lithium grease for cold temperatures in NLGI grade 1 (only a very thin coat). Petroleum jelly gets liquid at about 45 to 50° C, depending of the type.

 

[Chris Douglas]

Thanks for the suggestions, but there are no holes or slots in the retaining rings, just a knurled edge. Perhaps a special tool was used to engage the knurle. It may be pressed together, and not repairable, who knows. Sure wish I had a drawing.

Best regards,
Chris

 

[rjbuzzclick]

You could try using a rubber stopper that's about the same size at the ring to get some pressure on it to get it to turn. Just be careful that it doesn't rub on the lens element while you're trying to turn the ring.

 

[John Koehrer]

A second thought! A rubber stopper that fits inside the filter ring may do it.
Take yourself and the lens to the local Ace & check for a fit. One thing to be aware of though
is contact with the front element. Hold the stopper at an angle, hold firmly on the decorator ring & twist.
You may have to try a couple of places on the ring to get it.

 

[rjbuzzclick]

Ha! Great minds think alike!