Underwater Container?

[+stlhiker]

I'm working on a water trail cache in a popular park here in St. Louis. For the final stage of the multi, I was thinking of an underwater cache. I was just wondering if there's any guidance on making a container? I was considering an anchor like a cinder block and then having cachers unclip the container from it. Anyone have experience doing this kind of cache? It'll only be 2-3 feet underwater if that helps.

[+Chief301]

I haven't found any underwater caches yet but there has been some discussion here about a good, truly waterproof container. Some folks recommend Pelican dry storage boxes, which are fairly pricey, and if a finder happens to get a logsheet or something between the lid and the seal when closing it it's going to leak

 

I did find one cache the other day, though, which was not underwater, but it occurred to me that his design might make the ultimate waterproof cache. What he had was a length of PVC pipe, capped at one end, and with a plumber's plug inserted in the other end. A plumber's plug, if you're not familiar with them, is a sort of rubber plug with a bolt inserted through the middle with a nut or wingnut on it. There are washers on each side of the plug. You insert the plug in the end of the pipe (which is what it's designed to do) where it just fits, then when you tighten the nut it squeezes the plug between the two washers, causing it to bulge at the sides and wedge itself into the pipe tightly, making an almost perfect waterproof seal.

 

It seems to me that this would be a fairly inexpensive method and virtually ideal, as long as your finders know to tighten the plug when they replace it.

 

I'm keeping this design in mind, I'll try to incorporate it into one of my caches in the future.

[+Chief301]

Here's an example of what I'm talking about....you can get them for any diameter pipe, check at your local hardware store or plumbing supply, they may have them...

 

http://m.grainger.com/mobile/search/pipe-and-test-plugs/fittings/plumbing/ecatalog/N-a8f

[+wanderaboutaimlessly]

Here's an example of what I'm talking about....you can get them for any diameter pipe, check at your local hardware store or plumbing supply, they may have them...

 

http://m.grainger.com/mobile/search/pipe-and-test-plugs/fittings/plumbing/ecatalog/N-a8f

The mechanical plug or test plug is meant to be a temporary plug. I often see the metal plugs corrode and start to leak when left as a permanent plug. The wing-nuts are cast and tend to break if over-tightened. The plastic plugs seem to last longer but the bolt would have to be a non-corrosive type like stainless steel and might require an additional o-ring to prevent water from seeping in from the outside.

 

It sounds like a neat idea but may require a lot of maint.

[+Manville Possum]

Here's an example of what I'm talking about....you can get them for any diameter pipe, check at your local hardware store or plumbing supply, they may have them...

 

http://m.grainger.com/mobile/search/pipe-and-test-plugs/fittings/plumbing/ecatalog/N-a8f

Good idea. I also suggest placing a w/p match safe in the container for the log. I own a few under water listings, so I have experimented with different containers. I have one in place now that is not listed, but in test stage. I like this users idea about the plugs.

 

Good luck.

[+stlhiker]

Hmmm, really like the idea, but PVC containers aren't allowed in STL City or County Parks as part of their geocaching rules. WIll have to try another idea, possibly the Pelican box. I have a big one for my camera and it's waterproof and bombproof. Just need to swing by and pick up a smaller one for the cache.

[4wheelin_fool]

I tethered a few cinderblocks to an ammo box with a chain, and added a second line to the center which is attached to a floating water bottle. Yanking on the water bottle pulls up the lighter end of the chain with the ammo can, which has a few rocks and a lock n lock inside. I also used a second chain to attach the cinder blocks to a tree, so the river doesn't carry it away.

[+wanderaboutaimlessly]

found this while surfing

http://www.amazon.com/Underwater-Geocache-Container-with-Log/dp/B007VT58LY/ref=sr_1_46?ie=UTF8&qid=1344109768&sr=8-46&keywords=geocaching+containers

[+BBWolf+3Pigs]

I have had great success with these "test tubes". It doesn't take much to weight it down.

[+BAMBOOZLE]

Go to bed, bath, beyond or wherever and get one of those Stainless Steel drinking water bottles. Put some lead fishing weights in and suspend a bison from the inside of the bottle lid.

I've found several, some covered with barnacles , and the inside was dry....the bison gives back-up protection.

[+Jayman11]

I'm working on a water trail cache in a popular park here in St. Louis. For the final stage of the multi, I was thinking of an underwater cache. I was just wondering if there's any guidance on making a container? I was considering an anchor like a cinder block and then having cachers unclip the container from it. Anyone have experience doing this kind of cache? It'll only be 2-3 feet underwater if that helps.

 

Take a look at the OtterBox containers. They are rated to 100 feet. Very strong, nice latching mechanism and a large oring seal.

 

 

Or....if you are only going a couple feet, you could try a preform even.

 

 

[+Aurock]

I was thinking a preform would be perfect for this. I was just talking about placing such a cache today, where the container is attached by a string to something near the water's edge, the leg of a dock or such. At the moment though, water level could play a big factor in the hide. With the drought this year, the container would be farther in from where the water's edge normally is. When water levels return to normal, that means the container will be deeper in the water, and also that I need to be careful to place the out of water end of the string up high enough that it won't be underwater during a normal season.

 

Plus, the cache probably wouldn't be accessible for a couple of months out of the year, when the surface of the water is frozen...

[+stlhiker]

Got some more good ideas now, thanks guys.

 

I like the stainless steel bottle idea a lot. The preform tube could work too.

 

Just paddled through the area last night to scout it out. The water is murkier than I like so I'm not sure anything in the middle of the stream would work. Could take cachers an hour to find the darn final. There's a nice little set of waterfalls near the site. Thinking of anchoring something on the underside of a rock or something there. Wouldn't exactly be underwater, but would get you out in the stream. I've attached a few pics if anyone has some ideas.

and

[+WarNinjas]

Nice pics! I have a submerged cache out in the SF Bay. I took a water proof box bought at walmart. Wired it inside of a milk crate with some rocks and lead to keep it down. Inside that box a Lock n' lock with I think a water bottle preform or match container inside for the log. Just the water proof box has held up. But it don't hurt to have multiple layers of protection for the log.

This is how it looked a few weeks later. Outside nasty inside dry.

 

Then when being found months later still dry.

 

[+kissguy&frannyfru]

I'm working on a water trail cache in a popular park here in St. Louis. For the final stage of the multi, I was thinking of an underwater cache. I was just wondering if there's any guidance on making a container? I was considering an anchor like a cinder block and then having cachers unclip the container from it. Anyone have experience doing this kind of cache? It'll only be 2-3 feet underwater if that helps.

There is a cache near me that has been submerged in the Tenn-Tom waterway for over a year. I took a guy out to it last week,pulled it up and the inside was dry as a bone. The container is an ammo can. The outside looked horrible,but inside was nice and dry.

[+TwoBears Family]

was the ammo can weighted down with anything?

[+Cliff's Notes]

Cinder block anchor

 

JB weld soda bottle pre-form to inside of Gatorade lid

 

Log in pre-form, and Gatorade is the protection lair and could also hold the water neutral swag left behind.

[+DsrtMtnRox]

I like this topic....learning a lot! Can't wait to see more ideas! Thanks everyone!

[+Vater_Araignee]

stlhiker,

 

Do you weld? I'm currently working on an ER308 box for a UW cache. No hing for the lid just double ammo can style latches.

The best part is it's being made out of 100% scrap except the gasket.

[+kissguy&frannyfru]

was the ammo can weighted down with anything?

Yes it was full of rocks with a small thermos,also filled with rocks and a matchsafe inside of that. Turns out the extra containers were not even needed.

[+stijnhommes]

I saw a video of someone who found a cache underwater and surprisingly it was completely dry. Have a look at it:

[+Mike & Jess]

Be careful with the pellecan and other boxes similar.

 

I had done some testing a while back as I was looking to do a sumerged cache.

Using just the pellecan case (and a couple other variations), I placed a piece of tissue paper with juice crystals on it inside the container. The container was weighted down in a bucket of water, which was pressurized to ~20PSI. This was left for 2 weeks (each container tested on it's own) and found that all had moisture inside.

 

Now given my testing might have been a bit extreme, I was looking for a maintenance free cache.

 

One suggestion that came from a thread I had started back then was to use a wide mouth water bottle inside one of these containers. This in theory should work, as the water bottle is designed to keep water in, and with the two air chambers creating different pressures, it could very well work.

I have not tested this, but with my up and coming "tough cache" series next summer, I'll be testing this and other ideas soon.

[+duncanhoyle]

When considering making an underwater cache a friend once said that a waterproof container is only waterproof as long as the last finder closes it correctly!

I never got round to making the cache, but if I did I'd make sure that the log was made from a waterproof notebook