Care of rubber lens parts

[Konstantin Papadelis]

I tried the search option, but couldn't find anything. Maybe its my poor choice of words.

Some of my older lenses show whiteish marks on the rubber (focusing rings etc.). Not necessarily the oldest ones (Ai-S lenses) but specifically the AF-S ones (first generation 2,8 lenses).

Do you have a go-to method for those? My interest is in keeping them from losing moisture and maybe breaking in the end. I am thinking about appliying some silicone oil (sparingly, just on the rubber).

Some advice would be appreciated.

[Erik Lund]

Silicone for car door seals work well

[Konstantin Papadelis]

Very well. I'll give it a try. Thank you.

[BruceSD]

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For years I've used Armour All on all the rubber and plastic surfaces on both my cameras and lenses.   Makes them look like new.   

I buy and sell hundreds of vintage cameras and lenses every year. 
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[Snoogly]

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For years I've used Armour All on all the rubber and plastic surfaces on both my cameras and lenses.   Makes them look like new.   

I buy and sell hundreds of vintage cameras and lenses every year. 
.

Which particular product do you use?

[Zang]

What I did with my AI, AI-S lenses was, I took the rubber ring off completely. I deep them in solvent overnight to get rid of the stubborn dirt. I wash them with soap and hot water the next day using a toothbrush. Then I install them back to the lenses.