How to Waterproof a Geocache Container: 6 Steps That Work

You waterproof a geocache container by picking one with a built-in gasket seal first. If it doesn't have one, add a barrier layer of silicone or waterproof tape and drop in a silica gel packet. Then run a spray or submersion test before you hide it and it should come out bone dry.

What You Need First

• Container with a built-in gasket: ammo can, Lock & Lock or a screw top jar.
• Silicone sealant or waterproof tape for containers without one.
• A sandwich size poly bag as backup barrier.
• One or two silica gel packets.
• Sink, tub or hose for the pressure test.

How to Waterproof a Geocache Container: Step by Step

1. Start with a container that has a head start: A gasketed container like an ammo can or Lock & Lock box seals far better than bare Tupperware, straight out of the box.
2. Dry fit and inspect the seal before adding anything else. Close the empty container and run a finger around the rim, checking for gaps, cracks or a flattened gasket.
3. Add a barrier layer if there's no gasket: Run a bead of silicone around the rim, wrap the seam in waterproof tape or drop the whole container inside a sealed poly bag.
4. Drop in a desiccant packet: A silica gel packet soaks up whatever moisture sneaks past the seal from humidity or temperature swings.
5. Run a spray or submersion test before you place it. Hold the sealed, empty container under a hose for two minutes or sink it in water for ten, then check for any moisture inside.
6. Recheck the seal on maintenance visits: Gaskets flatten and tape peels after a few freeze thaw cycles so retest the seal every time you service the cache.

The Mistake That Costs You a Soggy Logbook

Skipping the barrier layer on a bare container is the single biggest reason logs turn to pulp.

• Ammo cans and Lock & Lock boxes seal well straight out of the box, no extra barrier needed.
• Bare Tupperware or a repurposed jar without a gasket lets water in within a single hard rain unless you add tape or silicone.
• A poly bag liner backs up any container, gasketed or not if the seal ever fails in the field.

Bottom Line

Not the price tag. A gasketed container, a barrier layer, a desiccant packet and a real test are what actually waterproof a geocache container not the box you bought.

Once your container passes the submersion test, the Geocache Container and Hiding Spot Ideas Generator pairs it with a real hiding spot, camouflage tips and a D/T rating in seconds.

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