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Negative weight camp pillow
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Dec 12, 2013 at 1:53 pm #2053646
See balloon bed reviewed here:
http://www.backpackinglight.com/cgi-bin/backpackinglight/balloonbed_review.htmlDec 12, 2013 at 2:04 pm #2053653"Baloon Bed" is my generic term for stuff that works in the backyard and not in the bush.
Here is one of the many reasons why :
Ryan , how long did it take you to blow up those 18 balloons ?Dec 12, 2013 at 3:33 pm #2053682Time… It took a couple of minutes. But it didn't feel any longer than it takes to blow up my neoair xlite. I only blew twice (medium sized breaths) for each balloon. I can also tie them really fast after working at a car lot for several years where we put balloons on cars every day. I can clock it later to make sure. I wasn't paying attention when I was doing it and on the trail a long set up could turn ugly.
I think the big difference between my style and the other two mentioned is the type of balloon. I discarded the long balloon idea right away (yeah, I thought of it, too). Those kind are easier to pop because of the weight distribution. My idea has smaller and spherical balloons that I don't have to blow up all the way, which makes them much tougher and they distribute more weight evenly. Plus the longer ones do not create as thick of a mattress. Theirs are 3 inches BEFORE they lay down. Mine is 8" before I lay down. I bet mine is MUCH warmer. If theirs pops a balloon the mattress has a major problem insulating. It would take several popping to create the same type of problem on mine.
If I can get some clip closures (so that the balloons are reusable a few times), I think my design will be better.
I just went to Wal-Mart and found some light weight strechy material that is really strong. I don't know what it is, but it weighs 2.9 oz. per yard on my scale and cost me $1 per yard. It feels tough enough to keep the balloons protected from sticks and rocks etc. Two yards ought to do. I will throw a zipper on for another 0.2 oz. The 18 balloons weighed 1.8 oz. on the scale. So, I will go ahead and throw it together: 7.8 oz. If I find some balloon closures those will weigh extra, but for now I will make this and then field trial it on a bunch of flint gravel from here in eastern OK. IF it can survive that, I am sure it will work just about anywhere at an acceptable level.
IF it works, I will get some lighter fabric (tyvek! Why didn't I think of that before?) and see what weight I can get it down to. Wish me luck.
Dec 12, 2013 at 3:37 pm #2053683Did I mention that those long balloons are HARD to get started. My cheeks and lungs hurt just trying to blow ONE up. Regular balloons are MUCH easier.
Dec 12, 2013 at 3:40 pm #2053688http://www.balloonsfast.com/balloon_clips.html
And VIOLA! Reuseable balloons. No tying necessary. And these guys look VERY light.
Dec 12, 2013 at 3:44 pm #2053689Cost:
$2 Balloons (24)
$5 Ballon Clips (100)
$2 2 yds. Fabric @ 2.9 oz./yd.
$2 Zipper (24")
$2 for nylon thread (800yds)Total Cost for a 8 oz. 8" thick mattress: $13 + tax.
Dec 12, 2013 at 4:14 pm #2053704Last RE: I promise. But I was looking through this review again and these are the only things that were counted as negative:
#1 Narrow (although a thicker/wider version is available using larger balloons)
#2 Balloons occasionally burst
#3 Time consuming set up
#4 Difficult to tie balloons with cold fingers
#5 Balloons are a one-time-use consumable itemAs to #1: You see my picture. If you think that is narrow… well… I don't know what to think. It's wider than I am!
#2 Is inevitable. But hey, My thermarest is eventually going to pop, too! Replacement cost is much lower and repair much easier with balloons. No wait time for any adhesive to set either!
#3 I will have to count breaths to see how many/long it takes to set up the neoair vs. 18-24 balloons. I will get back to you. I don't think there will be much difference, but I will be fair and do it at a relaxed, not rushing rate both times.
#4 & #5: see the website above and those two are completely resolved for mere grams.
So in the end the only beef is the fact that gear messes up sometimes… and set up time.
Um… really? Why don't more people do this? People go out with glorified blankets posing as tarps that they fold around (taking up to 15-20 mins.) in special ways with trekking poles and call it 'ultralight'. They spend hundreds of dollars on this stuff that is REALLY easy to tear, rip, and poke holes in.
But then if someone comes up with an idea that costs $10 and takes a little extra time (less than 3 min. extra, if anything) and a small risk of potential mess up that you can totally prepare for, and even if it weighs less than any comparable product on the market, everyone brushes it off as 'silly.' Wow. Someone needs to sort out their priorities.
I say this having done absolutely 0 field trials. But I am confident, as with all things, that any engineering obstacles can be figured out in a simple and effective way as long as someone wants to make it happen. Forgive me if the Brands lose customers because they can't find a way to market this themselves. ;) I will let you guys know how it works. I plan on setting it all up this weekend and really putting it through its paces.
Dec 12, 2013 at 4:16 pm #2053707I am interested to see how your complete solution works out. Be sure to let us know how it turns out.
Dec 12, 2013 at 5:53 pm #2053743I will keep you guys posted. I am sold on the idea and completely willing to pay for R&D. If it really works awesome, I will start selling them. I think this is a legitimate super cheap solution for MYOGers. I also think it will offer a better R value than other mattresses in this weight range. Especially if there's a mylar blanket in the mix somewhere (sewn inside the mattress case?). I don't know about testing R values, but I think this could hit 7 or 8 at least, maybe more. I could be wrong, I am ignorant about that stuff.
You know when you throw a water balloon and it refuses to burst? That is because it is under filled. Latex is REALLY strong stuff. I have been jumping, quite literally, on these under-filled balloons all afternoon and only two popped. Both times it has been because there was something underneath it, a lego for one and a colored pencil for another. I have kids. (:
This has shown me that pressure is what breaks a balloon, not the sharpness itself (unless it is REALLY sharp, I suppose). Sharp corners are just the focal point of that pressure. For that reason, I can already say that this will be recommended only with shelters that have bottoms or groundsheets. I wouldn't even sleep in my neoair on the bare ground, so that is probably not much of a problem.
I will have to take care with the bottom construction either way. I will keep you guys posted. AND a tally of balloons burst in the process of testing.Dec 12, 2013 at 6:15 pm #2053747Back in the day of rotary-dial phones, REI offered an air mattress with multiple, long air bladders inside a tougher shell of 8 or so long tubes. The idea was that you could carry a single extra tube for an instant repair and even if you lost a tube, you still had 7/8 of them inflated.
I like your idea of going even lighter on the inner bladders. If you keep the diameters small, the forces on the fabric and the stitching will be less and you can go to very light fabrics. Also, if the outer sleeve is smaller than the compressed balloons, the balloons won't take the force – the balloons will only be the air-tight lining.
I'd suggest a slip-cover that you fill from the middle with the small balloons, so you don't have slide the inflated balloons the entire length of the outer sleeve.
Dec 13, 2013 at 8:15 am #2053889Great idea with the filling from the middle. I will put the zipper in the bottom in the middle. I figured the sack would take a protion of the force. That is why I got a really tough stretchy lightweight material. To give it some give, but keep it tough. I think tyvek will work really well too, but I am REALLY liking this other stuff.
By the way guys, when I bought this stuff at wal-mart (I got it on the sale rack) they had four partial rolls of Sil-nylon that they had absolutely NO idea what it was. It was labelled as "unknown fiber." I got two 1 1/2 yard pieces for $1.50 per yard and the remainder on a roll that ended up being 9ish yards long in two pieces ($0.50/ yd on that!!!!). It is the 2.25oz./yd stuff. Ugly olive drab stuff, but awesome price. I bought them out. You should check there occasionally. I never thought Wal-mart would have this stuff.
Checked it at home. Put some water on some last night and left it. Still no leaks found. I was afraid I would find some. You know how fabric ladies love to poke those little pins in everywhere. This stuff seems perfect.Dec 13, 2013 at 8:38 am #2053905Speaking of using helium filled balloons:
Sectionhiker had an April Fools post on it. Good stuff.
Dec 13, 2013 at 9:18 am #2053924"…They spend hundreds of dollars on this stuff that is REALLY easy to tear, rip, and poke holes in.
But then if someone comes up with an idea that costs $10 and takes a little extra time (less than 3 min. extra, if anything) and a small risk of potential mess up that you can totally prepare for, and even if it weighs less than any comparable product on the market, everyone brushes it off as 'silly.' Wow. Someone needs to sort out their priorities…."
People don't think it is going to work. Personally, for me, blowing up and tying all those balloons sound like a real PIA even if you use clips. It sounds pretty annoying the other way around. Try not to get to upset because people don't initially accept your idea…. prove us wrong.
As far as insulation goes, I think you are going to find it does not perform well in the field. On your living room floor tells you nothing about the insulative properties of a bedding. Insulation doesn't mean anything when there isn't a temperature difference (there is no heat flow to stop).
In the field heat loss occurs three ways (the three forms of heat transfer): 1. conduction, 2. convection, 3. radiation. You've suppressed conduction by putting a layer of air between you and the ground, just like all other air mats. Yours is thicker so it might be better except for convection. Your large unrestricted air chambers will be a perfect environment to circulate air underneath you. Down in air mats stops that circulation. Since down seems to add quite a bit to the insulative properties of air mats that makes me conclude that air circulation is a significant driver of heat loss.
The third driver of heat loss is radiation. Down acts as a radiation barrier too. Your system does not have any alternative radiation barriers. Regular balloons are not particularly good at reflecting radiative energy. Metallized mylar balloons (those part balloons) have better radiative properties, though I am not sure how well they would work. In general they are stronger than regular balloons, but they are not very flexible. Your underfilled regular balloons flex with the environment quite well which gives them the durability you have noted. And, although the radiative properties of mylar balloons is quite good, a radiation shield needs to be between layers (with an air gap on either side). I am not sure how much radiative benefit you would get.
Anyway, keep up the good work and don't get discouraged by us doubters!
Dec 13, 2013 at 10:56 am #2053960Ryan,
Just to give you some ideas –
What looks to be a partially inflated balloon is a "balloon pump".
I pulled these images from a BPL article. Membership is required.
Also, Google around the site for Bill Fornshell .
He was a very early out-of-the-box SUL innovator, and you are following in his footsteps.
Best of Luck.
Dec 13, 2013 at 7:02 pm #2054111Thanks Guys. Especially you, Ben. You have given me a lot to think about. I mentioned in one of those posts about sewing a mylar barrier in there. Now I am wondering if a wad of mylar might not be put inside the balloon itself (like my neoair xlite). As the ballon expanded, the mylar would naturally spread back out).
5 minutes later:
Okay, I did it. Using an emergency blanket, a rotary cutter and a plate…
Putting it in the balloon was as easy as using a stuff sack. Then I blew it up:
Credit to Ben for telling me about a way to make this better! Now what was that third way to stop heat transfer?
I have read a few threads of Bill's. The Backpack was awesome. In fact, I just finished reading the SUL/SUC thread. He is like my superhero.
Dec 13, 2013 at 7:05 pm #2054113Did I actually fix both of Ben's concerns there simultaneously? I mean, I stopped the air circulation (at least a little) and I took care of the radiation with the mylar. A few tweaks will have this perfected. Another R&D aspect to focus on.
Dec 13, 2013 at 7:48 pm #2054119Thanks, hun! I would need to do calculations, but this shouldn't add too much more weight. Depending on design and fabric (Balloons are negligible at 2g each), I think I can stay under 6oz. for this one, using a lightweight nylon.
Forgive the simple MS Paint Job:
Dec 13, 2013 at 7:52 pm #2054121That is a combination of mine and Bill's idea. His on top, mine on bottom. Air convection is stopped. Radiation barrier in the middle. Weight still ultralight. Balloons still cheap and easy to pack in replacements, if required. REusable with balloon clips.
Wait until this weekend and I will actually clock myself blowing up my neoair and the balloons (and clipping them). I will let you guys know the time difference. I have some sewing to do between now and then…
Dec 13, 2013 at 8:03 pm #2054123Okay, this is just plain silly. But I couldn't resist. If I make it out of waterproof material, this could even be a raft for your pack on crossings. Or just a raft for fun…
Dec 13, 2013 at 8:08 pm #2054125Seems like you could rig up a cuben poncho to also work as your mattress cover – dual use!
Dec 13, 2013 at 8:31 pm #2054133Absolutely. I get sick and tired of carrying around rain gear and not having anything else to do with it. GOOD IDEA!
Dec 13, 2013 at 8:49 pm #2054135Dec 14, 2013 at 6:33 am #2054169About the mylar thing, couldn't you use those space blankets/emergency blankets as your mattress cover, or are those too fragile? Seems that would solve the cold problem.
Dec 14, 2013 at 7:58 am #2054183…
Dec 14, 2013 at 8:36 am #2054190I love it Ryan!
Yes you are addressing all three heat transfer methods. The air reduces conduction. The Mylar would act as a barrier to both convection and radiation.
The mylar stuck in the middle of the balloon worked pretty good. It does settle a little to the bottom so it would still be possible you might get a bit of convection in the top, but it will be really interesting to see how this works out.
Your combo pad will most certainly be warmer, but it seems like even more of a PIA to blow up 2 layers of balloons. Plus you have quite a few layers of fabric that will add up weight fast.
I think this is pretty far off topic for a thread in the gear forum titled "Negative weight Pillow." Can I suggest you create a new thread in the MYOG forum dedicated specifically to this project?
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