Thursday, September 16, 2010

Building the bouy, thinking about hampture Mk.II

Drove down to Target this afternoon and after deftly weaving through the herd of overweight women each leading a small circus troupe of screaming children I managed to escape with a small plastic tub and a drill bit that is exactly the same diameter as aquarium air tubing. Things I did not find were hot glue guns, fishing line (to anchor the bouy) or dignity.

In the course of navigating that glorious monument to capitalistic excess/fatty zoo I noticed they carry water cooler jugs. Huge, cylindrical, made of sturdy transparent plastic and they come with their own watertight caps. "Holy shitballs" I said outloud after waiting for children to wander within earshot, "This would make a perfect enclosure for Hampture Mk.II". Moments later my two brain cells began to rub together and it occurred to me that I wouldn't actually be able to get the necessary equipment *inside* there as the opening was too small (giggity). I'd need something I could fully open up and then, when everything was assembled, seal in a way that water wouldn't get in. It'd need to be rounded, transparent and made of very sturdy plastic as Hampture Mk2 will be a minimum of 8 feet underwater, possibly more depending on what point in my downward spiral into depravity I am at by then. I have no idea what sort of container would meet those specifications (sturdy transparent plastic, large but not too large for one person to move around, rounded shape, can be opened but is also watertight when closed) anything you can suggest would be appreciated.

I searched around to see what other people had done, and found this astonishing nonsense.

Their hamster sub uses two hoses, one to feed air into the sub (via hand pump) and the other to return stagnant air to the surface. I won't be using an exhaust hose for Hampture Mk1, but I'll need to for Mk2 due to the greater pressure making the use of a moon pool problematic. I'll also need an air pump far more powerful to push fresh air down that far. I considered using two car batteries and an inverter to power something like this, but then in an epiphenal realization of my own stupidity I remembered that there exist compact battery powered automotive air compressors. They'll run for hours, are relatively weatherproof, offer pressures around 260psi and it'd save me the trouble of wiring up the batteries with the inverter and waterproofing all of it. Obviously that powerpack would be in it's own waterproof tub, though. We're talking about a support bouy sufficiently large (probably 3 feet by 2 feet by 1 foot) that it's pointless unless the habitat is much, much bigger than Hampture Mk1. and much deeper as well.

I'm getting ahead of myself, though. I can't afford to build any of that unless Hampture Mk.I pans out and I get enough donations for that power pack, as it's the most expensive component of the MkII habitat. With any luck, the MkI prototype will prove the viability of the concept and it'll turn out that you're all fascinated enough by the prospect of a large scale deep water mammal habitat that you'll fund Mk II.


  1. I doubt you'll be able to find anything that can both open and close effortlessly AND withstand the pressure of 8 feet of water. You'll probably have to glue whatever it is shut before you put it down there and cut it open again when it comes up.

  2. I'm thinkin' if it's a clear tub like the one in the picture (but much larger) I can simply turn it upside down and make the lid into the base. I'd gorilla-glue a baking pan very slightly smaller than the lid onto it, so as to keep the 'ground level' above where the water could reach even if it got in, and I'd fill the pan with a mixture of composting soil and nontoxic dessicant (to dry the air.) I've done a couple of concept sketches, and I think 260psi is sufficient overkill that even if it's not that watertight it should suffice.

    I am concerned that a rectilinear container won't withstand pressure as well as a rounded one, but if it's sturdy enough it should hold anyway (it's just not as efficient as I'd prefer) and flat surfaces will permit me to see inside without any distortion while it's underwater. That means I could conceivably buy a waterproof digital camera enclosure and shoot some footage from outside the habitat.

  3. heres an idea i had to make the actual underwater enclosure. its presented in the format to which you are accustomed.

    connecting the tubes would be kind of a bitch though. i'd use one of those ribbed hose connectors (like you find on the end of a bunsen burner), and try to find one where the other (non-hose) end is threaded. then cut a hole in the top of the enclosure, and bolt the hose connecter through the hole with rubber gaskets and washers (as above).

  4. Excellent diagram. I'm not even sure those screws and caulk would be necessary though. I was thinking of supergluing a soft rubber strip along where the lid meets the edges of the tub, to form a seal. But that would be for the tub I use for Hamputre Mk.II. I'm not sure if it was clear but the one in the picture is for the support bouy; to keep the battery powered air pump safe from rain, and to make it float above the habitat, that sort of thing. The tub used for Hampture Mk2, if I went with a tub, would be much larger.

  5. Just a thought, but if you're planning to mix the desiccant with the composing mixture, you might encounter problems. There will need to be a minimum level of moisture for the bacteria, fungi, and protozoa in the composting soil to remain active. If the desiccant is mixed in directly with the soil, you could encounter problems.

    I'm not certain on this, though. Perhaps you could do test runs of a couple of weeks above water, to test whether or not the hamsters would end up lost in a sea of their own poop, and whether any plants you introduce would grow or not. An easy alternative would be to have some sort of hanging apparatus (out of reach of curious mammals) that could contain the desiccant.

  6. My observations could be wrong here, but it appears that you have provided in your drawings nowhere for the hamsters to make beds. Every hamster I have ever owned enjoys little more than making themselves a cozy bed out of woodchips, etc.
    If you do intend to provide them with something to make sleeping arrangements, will they not make a mess of it, and get it in the moon pool?

  7. Hm. After reading the above two posts, I'll be using a mesh sack for the dessicant, and some fabric secured to the side of the habitat for a bed.

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