How to keep collapsible natural rubber lens hoods in good condition?

[MartyNL]

AI tells me;
"Natural rubber degrades over time. Exposure to factors like heat, oxygen, ozone, and UV radiation can cause natural rubber to deteriorate and become brittle, cracked, and lose its elasticity."

Does anyone know or have experience with easily available products that can be used to preserve the qualities and longevity of collapsible natural rubber lens hoods?

And that isn't detrimental to lenses.

Or are we consigned to repeat purchases of our favoured collapsible lens hoods or replacing them with plastic or metal?

Pictured, is my 105mm Heliopan for my 100x100 filter system.

[Drew Wiley]

You can go to an auto store and find a selection of dashboard treatments like Armor All. But I'd be personally hesitant to have substances like that in proximity to a lens. It's just a matter of time anyway. Go metal, or better, a bellows-style compendium shade. You can also think of a "flag" on an adjustable arm.

[phdgent]

For keeping rubber from getting (more-) brittle, I treat it with Ballistol gun oil.

This more than 100 years old German mineral oil is renown for being very polyvalent.
Motor bikers used it to use it to keep the saddles, rubber cable sheaths and steering handles from deteriorating in the sun.

It was used by horsemen to take care of their animals and rigging, soldiers to care for their weapons and leather parts of the uniform, gunmen to lubricate the loading sleds, marines to protect their weaponry from the salt corrosion, photographers to care for the camera's leatherette (Leica) and bellows (Linhof), relieving from insect- and plant bites, and go on and on...

It is very useful for lubricating delicate mechanics too as it dries without getting sticky and it somewhat penetrates in the fine surface structure of some metal parts. It solves dirt too (besides burnt gunpowder).

It is said that Rommel lost a battle in the desert war due to the allies bombing a supply truck transporting a shipping of that oil, but that may be a des(s)ert legent.

Don't fear to use it near optics once it got the time to drie (overnight) and all the valors are gone.

PS: sorry for repeating myself...

[BrianShaw]

My rubber hoods failed after a few decades in use. I replaced them with metal hoods. The best decision I made in years.

[MartyNL]

Thanks for the tip, phdgent. I'll think I'll give this a whirl.

[MartyNL]

I've got Heliopan metal lens hoods, very nice but not as wide as the rubber. And I've got 2 Linhof compendiums. The small one is too small and the big one is a bit on the large side.
If I can get a few decades out of the rubber hood, I'll be a happy camper.

[BrianShaw]

Another option for rubber protection would be silicone spray. Some sources, including Ballistol, seem to recommend that over mineral oil while recognizing that mineral oil most likely won’t cause any damage.

[BrianShaw]

Regarding width of the hood/shade, there’s a whole science behind sizing. The collapsing rubber ones seem to always be wider, and sometimes shallower, than those “specifically designed” for a specific lens. The benefit of wider is ease of filter installation and the benefits of collapse speaks for itself. Yet wider is not necessarily a benefit from the optical perspective. These differences may be minor and even insignificant but some believe them to be important in some critical situations.

[Alan Klein]

Wouldn't oil, or other solution treatment of the rubber, rub off on your hands and possibly onto film and lenses? Seems risky.

[George Hart]

Talcum powder