Leak-Proof Water Blob Provides Hours Of Fun

With the warm weather slowly creeping back it’s time to think of warm summer days, and with that comes this rather interesting leak-proof water… blob?

[Leisha] over at Homemade Toast has come up with a super inexpensive way to make a water blob  — or a giant outdoor waterbed? It certainly looks cool, and apparently keeps children entertained for hours playing on it. We wonder how bouncy you could make one for bigger kids (i.e. us).

It’s made out of a roll of painter’s plastic drop sheet, and instead of trying to tape, glue or otherwise seal the edges, [Leisha’s] figured out an easy way to melt the seams together using a clothes iron. By sandwiching parchment paper over the two pieces of plastic, you can gently run the iron along the edge, creating a very strong bond, without melting a hole in the plastic.

Seriously — we want to see someone make a giant version of this for some extreme waterbed bouncing!

[via Viral Nova]

43 thoughts on “Leak-Proof Water Blob Provides Hours Of Fun

      1. You could put one bag inside another, with an air gap between them, or maybe even several smaller bags in the big one. So it’d need a good amount of damage to make it sink.

        Still I do see your point, it would be a bit unnerving, a big sheet of enveloping, tangling, plastic wrapping itself round you as you’re trying not to drown.

    1. Mythbusters tried that once. By the point they’d inflated half of their colossal plastic bags, they had to evacuate the giant hangar they were in because people were suffocating on the leaking helium.

      Actually they made quite a meal of it, the thinnest plastic they could get away with, to make an airborne “raft”. Looks like it’d have been a lot simpler to just knock up a zeppelin, or some balloons.

      That’s something I’d like myself. Balloons or a Zep attached to my belt, taking say 90% of my weight. With only 10% of my weight to support, I’d be able to make massive jumps and bound around town.

      1. I made a hot-air baloon with the painters-plastic. Thinner stuff than the 4 mil stuff here.

        What worked is that the balloon went up. What didn’t work is to keep it under control with fishers line. When 64 cubic meters of air starts moving, it actually has momentum. The 64 cubic meters of air weighs in at around 75 kg, as much a (non-overweight) human being.

        1. I’d never thought about that. RE:the blimp “stat” that just got loose the other day, given the size of it that even the lifting gas alone (never mind the envelope or payload) would give it enough inertia to even overcome loss of lift for a while. Predicting this thing’s touchdown point was likely a worst-case nightmare for those responsible.

      2. If you could get some weather balloons and a used parachute harness you could probably make something like that, but it would need a quick release and have to be done in an open area in case a wind gust caught the balloons.

        1. Hm, interesting to have to take the wind into account if I was only gonna weigh 10 kilos (weight! not mass! as my physics teacher endlessly pounded into our futile little heads). I figure in case of emergencies, just pull one of the balloons down on it’s string and bite through it, amusing myself with squeaky voice impressions on the way down.

          Still, your idea’s pretty practical! Worryingly, excitingly so!

          I once tried something similar to Roger, making balloons with a friend out of sandwich bags and tape, filled with a hairdryer. Worked well indoors! I think there was too much surface area, or not enough insulation, for outdoors, the heat just disappeared in seconds. A little alcohol burner strung underneath was useless.

    1. More than you think.

      Litre of water weighs a kilogram, occupies a cube 10x10x10cm (4″). Or 1ml is 1 cubic cm and weighs one gram.

      TFA says the blob is 10′ x 10′ x 8″, so roughly 300 x 300 x 20cm, so has a volume of 1,800,000ml. Divide by 1,000 to get litres (and kg), so 1,800.

      Roughly 1.8 metric tons.

      (2.2 pounds to the kilo, so 4,000 pounds)

  1. ~25 years ago. Old queen size water bed. Attached a hose to it (in the back yard). Kept filling until it was roughly 5ft high and felt near hard as steel. Sat on the roof, and fired about 50 BB’s into it in a nice spread pattern. Worked as a killer water slide for about 10 minutes until it split open. The water sat seemingly suspended in space, then fell, covering the whole yard in about 2″ of water!! Ahhhh…. such fun… memories….. :)

  2. There is an adult size blob at The Rock Ranch in Georgia. It has been a couple of years, but it must be at least 20′ x 30′. I believe it is full of compressed air. Supposed to be for kids, but if a couple of adults get out of sync, you can get some serious air.

  3. It’s all fun and games until a kid accidentally punctures the thing without bursting it, falls inside and drowns.

    Don’t let little kids unsupervised thinking that is safe because are just a few inches of water.

          1. First I laughed at this possibility: I thought it was impossible to a baby to puncture the plastic, fell inside and drown. Well, it is possible.
            Yesterday I built this waterblob for my toddler girl, and she loved it very, very much! I never saw her having so much fun! And the “leak proof” part lasted for only five minutes…
            I stood besides her all the time, as I would never leave her alone playing with a weapon of mass baby destruction. All looked safe, until she tore a rather large hole on the top of the waterblob. She put her foot inside, sit inside, but didn’t even put her head inside.
            So I think this can kill a baby, but only if the parents aren’t paying any attention at all. It’s perfectly safe otherwise…
            This morning the water blob was drained, the plastic ruined, but I think it was worth the effort.

        1. I’m sorry, but I MUST chime in here.

          At a VERY early age my parents did (for me) the kindest thing-at about age 4 (or so) allowed me unfettered access to deep water-defined as such as about 3 feet, 11 inches deeper than is the current “limit” defined as “safe” (IOW about 4 feet).

          So here I am, at a very early age, a true child of Poseidon, and pretty much drown-proof. My childhood nickname was “bubbles”, as I was frequently found at the bottom of the pool blowing them…

          I took this to great advantage from about 1993 to about 1999. I was pretty much the only insane idiot on southern Lake Michigan still out until late November-on a high-performance Jet Ski.

          Until you’ve done it, an eleven-foot wave front is but an abstraction. Feeling one under you is something else. Getting launched from one…well, need i continue?.

    1. Unless the baby lied face flat down, I’m sure it’s unlikely that the baby would drown in a feet-deep “pool” of water. Also, I watched somewhere that babies won’t drown that easily, and can swim even.

      1. Babies can sort of swim, but i wouldn’t trust them to keep their head above water.

        Also, swimming in a couple of inches of water on slippery plastic doesn’t work, it would be quite likely that the baby couldn’t get up on all fours but just kept slipping and getting it’s face under water until it drowned.

        This is a great, fun and safe toy with proper supervision even if i would probably try to get something more sturdy than painter’s PET sheet. Something like rip-stop vinyl sheet would probably be better, or even cloth backed vinyl or polyurethane. Either that or cover the thing with something so it’s harder to rip.

  4. There have been very rugged “blobs” at the World Expo in Hannover, germany (Year 2000 roundabout). Have been there as a kid. Surprisingly, they’re not very soft. Learned the hard way by performing a class A belly pop on one of them…
    Nevertheless, very cool idea. And comfy, when you just sit around.

    1. Hmm.

      Blob surface area is ~10 square metres.
      Sunlight is 1000W per square metre.
      A joule is 1W per second.
      ~4 calories in a joule.
      1 calorie will heat 1ml of water by 1 degree Celsius.
      Blob contains ~1,800,000ml of water (as above).

      Calories per second is 10 x 1000 / 4 = 2500.

      Temperature rise per second is 2500 / 1800000 = 0.0014C.

      After an hour (3600 seconds) temperature would rise 5 degrees.

      8 hours would give a 40C increase, you’d end up with water hot enough to shower with.

      YMMV, as this is “assuming a spherical cow in a vacuum” stuff. Still, this is exactly the theory behind solar hot water systems.

        1. Halve the amount of water (100mm vs 200mm thick) and it’d be fairly impressive.

          You can get “solar camping showers” that are the same idea, a black plastic bag full of water with a nozzle attached. Not quite 1800 litres though.

Leave a Reply to peterCancel reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.