11.4 oz 78x20x2.5″ Sleeping pad :)

Nice, I really like this. How much did all the materials cost ( minus the iron)? And how long did everything take to make this?

Bender,

That is one sweet pad!

Now the question is……..

How much to make one for me? :)

Awesome job! Now, you just have to put some down in the tubes. :)

Todd I'm going to keep testing this one for a while. If all goes well I may make some more! I have some ideas that would greatly speed up the process but it would require getting a Mono Kote iron and modifying it. I wish I could find the material less than $16 a yard and stupid high shipping.

Steve I actually was thinking the same thing. If my calculations are correct I could make a 72" 800 fill power down version that weighs 14 oz! I know down isn't good with moisture but it may have a slow self inflating affect.

Just an idea on the seam sealing, probably not worth it just for one mattress, but… In a book on making geodesic domes I read about someone grinding the side of a big soldering iron flat, drilling a hole and bolting on a ball bearing. The bearing got hot enough when the iron was heated to heat-seal polyethelene sheeting – easier to control the speed since it rolled rather than having to slide.

Paul thanks for the tip. I have actually been on some of the hobby forums and found a similar idea. They were sealing material for blimps. The one I liked was just an adjustable soldering iron with a wheel instead of a soldering tip.

Just a tip on the insulated ones – if you look at the insulated BA air cores, they use synthetic insulation. and the insulated model is only 2 oz over the regular. so the down may not be worth it.

Kieran your right the BA insulated pad is only 2oz more but there is one small catch. The insulated pad uses 50D ripstop and the uninsulated version is 70D. That's not a bad thing, I just can't do the same trick. I would estimate they are using 5-6 oz of synthetic insulation. Anyway if I stuffed one of mine with down it would still end up being 10 oz less than the BA insulated. Now who wants to send me some 800+ goose down, preferably detached from the geese!

I used a tiny amount of JB weld so the valve can't be pulled out. The JB weld actually helped get the valve completely pushed in flush. I am actually amazed at how well the valve area turned out. I was expecting this to be this designs weakness but I no longer think so.

sneaky devils! oh well… so when does an insulated version go on sale? :)

using 2.5oz XP would add 3.125oz. It would be easy to make and more resistant to any moisture trapped in the tubes. If you don't i think i'm gonna have to try making one like that.

Also, i have a lot of down, how much do you need? email on the down please tmarshall charterinternet com

-Tim

Tim check your email. Is the XP insulation in sheet form?

Here is my pad next to a BA Air Core which is 2x the weight and packed size!

yes Xp comes in sheets from thru-hiker.com

60"xnum yds ordered.

-Tim

Tim,
If you use XP and insert strips after the mat is welded, how do you keep them from twisting to vertical in the tube, and creating 2 uninsulated channels?

good questions, i haven't even though about it at all. However XP melts easily at low temps so i would guess that where the pad was heat sealed the xp would seal in there 2, maybe i'm way off though. I was thinking of putting the xp in before sealing.

Maybe i'll have to get some 30 heat seal able nylon and just try it out.

-Tim

Tim,
What R Value do you get from a single layer of XP?

I assume the additional air spaces would contribute, and would be a 'plus something' in the down the road guestimations.

Thanks.

don't know the r-value, but is it safe to guess that it would insulate equally as well above or bellow the sleeper? (if uncompressed)

If so then 2.5oz XP to 45*, 3.7oz COMBAT 35*, 5ozXP 25*, 7.4ozCOMBAT 15*.

Should be warmer in the pad than in the quilt as the air is trapped and can't escape resisting change in temperature longer right?

-Tim

I like where this is headed!

I've heard some say that making one layer a solar blanket, so long as it isn't directly touching you, is a great thing to have in your padding "sandwich" – so maybe layer one of those in also?

VERY cool! What width does the fabric come in? I'm interested in making a wide pad – 25", or even 30".

How does the fabric feel as far as durability? As strong as the BA material? More fragile? Similar?

Really interested where this one goes. Thanks for sharing!

Curt

I wouldn't go as far as to say the material is as tough as the BA but I do think it will be tough enough for most people. The material comes 56" wide so you could easily make a pad but not the same way I did. Instead of folding the fabric you could have a top and bottom piece but you will waste a bit of material. If you want to waste the least fabric you can fold the fabric and just make the tubes horizontal instead of vertical. This would give you a pad over 25" wide when inflated. You would need roughly 3.25 linear yards to get a 72" pad with horizontal 2.5" tubes. FYI the material is 91.5g per square yard so that pad would be about a pound with valve.

Now what would you all think if I told you I had a working prototype electric air pump capable of filling a standard sized sleeping pad in 20-30 seconds? What if it weighed less than an ounce and was good for 10-20 inflations per charge? Hummmmm, that would be nice! I'm still working on it so don't expect pictures anytime soon.

I was thinking about integrating this with a down insulated version of my sleeping pad. The current 78" pad is now 11.3 oz because I trimmed the excess material around the edges this weekend. Were talking 14-15 oz total for a 72" down filled sleeping pad with a very nice built in pump! This totally solves the manual inflation problems with moisture and down. Do guys think a pump is worth an ounce?

The lightest pump that I know of for that purpose is the Big Agnes Pumphouse, 1.5 oz.
Maybe a simpler way to do it ? (stuff sack/pump combo)
http://www.bigagnes.com/Products/Detail/Accessory/Pumphouse
Franco

yeah i would think a pump would be worth it only on the down version because of the condensation issues. I would imagine after a week long trip that down could get fairly soggy.

"Do guys think a pump is worth an ounce?"

Absolutely.

An even bigger plus is the time reduction. A Stephenson DAM "stuff sack inflator" takes about 15 fills to get a DAM up to snuff, requiring a fair amount of time and patience – Something I'm often short of in the dark and cold.

I'll be waiting.