I was thinking, whats the best substance/material to use to preserve the rubber gaskets on ammo cans (or other waterproof containers?)
I don’t want to seal the container permanently, I simply wish to maintain the integrity of the gasket and keep it from drying out.
I was thinking some type of silicone or something. Any ideas?
I don’t know about using it in concert with gaskets, but wax is an excellent waterproof sealant, and you can keep it sealed as long as you want, break the seal easily, and just as easily re-seal it. The only problem is that of course the sealed containers can’t be exposed to extreme heat.
Silicone spray lube, available at most auto stores. Armor all has water in it and isn’t a good idea unless you want to have to keep putting it on like every week.
The problem with gasket materials is that you have to think very long-term, and you really have no way of testing what you’re doing long-term. Gasket materials are a very specialized field. If the gasket is old and has gotten hard enough that it doesn’t spring back when opened, so that it no longer seals tightly when closed, there’s really nothing you can do that’ll be guaranteed to be effective except replace the gasket. And there are basically no replacement gaskets available (that I’m aware of), so you’d have to improvise.
As far as treatment of existing gaskets goes, Armorall contains plasticizer, which will help extend the life of some, but not all, gasket materials, but it has to be applied properly, left to soak in, and wiped off. Even then, it outgasses (a dash that’s been Armoralled will outgas and deposit a film on the inside of the windshield in the sun). I have no idea what this might do to ammo or food stored long-term.
Silicone might or might not improve performance, but you’d have to test for compatibility with the gasket material, and you have no way of testing long-term performance.
New gaskets made of silicone, like the tubes of liquid silicone gasket material you can get in auto supply stores, will form great gaskets, but only for one use. And they require moisture to cure and generate acetic acid (the vinegar smell when curing). Again, the long term effect is unknown.
Gaskets made of other common materials, such as inner-tube neoprene, would probably work well, but again the long-term results would be unknown.
Another way to try to improve the gasket performance is to lay a sheet of very flexible plastic, like glad-wrap, across the box before closing it, giving another layer of thickness and an additional barrier to moisture. Again, long-term performance would be unknown, but I’ve successfully used that method to help keep paint and other canned liquids somewhat longer.
The newer the original gasket, and the less it’s opened and closed, the longer it’ll last. I don’t think I’d fool with it too much. If the boxes are old, get newer ones unless you want to take chances testing gasket materials.