Cuban quilt…it’s gotta be done

[Lynn Tramper]

I have been thinking about this for weeks now. I even slept using my Refuge-X as a blanket to see what the fabric is like for this use. I figure I can make a quilt, much along the lines of this one

http://www.backpackinglight.com/cgi-bin/backpackinglight/xdpy/forum_thread/11371

The differences would be
a) silk baffles
b) a velcroed closure along the bottom baffle that is covered with silk to allow the air to escape when packing
c) the baffles will be attached to the cuban with cuban tape to make it almost completely waterproof (ie no seams exept the edges and fabric joins).

I am also contemplating an openeing so it can be worn as a serape…not sure about this, and tie-outs along the edges so it could potentially even be pitched as a shelter.

Dimensions, around 66" at the shoulder, 52" at the foot, 74" long, baffles at 6" intervals, 2.5" high, fill weight ~10oz. I'll go with the gossamer light 0.33oz per yard fabric, with a guesstimate of ~7 oz for the cuben, 3oz for the tape, 1oz for the baffles, for a total of 21oz. I would conservatively guess it would keep me warm down to almost 0F when used with a skaha hoody.

For you hard-core ULers, this could be scaled down to Arc alpinist dimensions for a truly UL waterproof VBL sleeping experience.

Yeah, it's really wide, but that's how I like it, so it can be virtually turned into a "bag", and can also be used as a two person quilt.

Waterproof, light, VBL, shelter, insulated clothing…what more could I want in a quilt? Well the down sides are gonna be cost (yikes), crinkly sound (but I'm OK with that as I don't move much in my sleep), non-breathable could get sticky in warmer weather, durability.

[Adam Rothermich]

Bill made something similar to what you are envisioning. Here's a link to his blog post. He also made an all Cuben sleeping bag, but used synthetic insulation. I believe there are threads on each of these projects on this site but I'll let you sift through the search results if you're interested.

Adam

[Lynn Tramper]

Thanks Adam.

I've read Bill's posts and was partly inspired by them. The biggest difference is working with baffles and down, and making this a WARM sucker. Bill's quilt looked like it might be OK for summer trips in this part of the world, but I'm not a fan of the synthetic insulation (heavy for the warmth), plus since cuban is waterproof, it will be ideal for protecting down in all climates. His quilt was also majorly too small for my tastes, and no way would it work for couples. I'm hoping this will be a true 4-season 20oz double quilt, eliminating any need to carry a bivy bag for damp and windy conditions.

I think I'll pass on the serape design. Seems like a good idea, but a lot of folks with the No-Snivellors don't really use the feature much. I can always retro-fit a hole, but at this stage I feel it would compromise the waterproofness of the design.

[Michael Wands]

I am kind of leary of using down insulation with a shell that does not breathe. Even with a quilt design I would be concerned that it would be soaked in the morning.

A combination sleeping quilt, serape, shelter is a great idea and should be pursued. It could be the ONLY piece of gear that you would need to take. The ultimate in multi-use gear. This would be a step back to the days when a travelling cloak did everything.

Pretty exciting. Let us know how it turns out.

[Lynn Tramper]

I'm not so much concerned about the down getting soaked as I am about ME getting soaked. In my 'trial' I wrapped a Refuge-X around a down quilt and spent the night in it. I was surprisingly dry in the morning, but it wasn't a cold night so I never had to cinch the quilt around me enough for persperation to accumulate. In colder weather I can expect my sleeping layer to be somewhat damp by morning, but that drys pretty quickly.

I like the idea of a travelling cloak and hiking staff…maybe a pouch of tobacco to put in my pipe, and a hunk of cheese and bread in my napsak, just like in the good old days. I suppose that would mean some wine in my wineskin too ;)

[Brad Groves]

Allison, I was getting all geeked up about making a Cuben quilt too. But I read a post somewhere here where someone (most likely Bill?) had built an all-cuben quilt or bag–and had condensation problems in the insulation. From what I recall, the poster felt that the differential between the cool outside air and the warm air coming from inside caused the inner-layer condensation. That kind of stopped me, which was a bummer, 'cause I really liked the idea of a waterproof, VBL, uberlight bag. Not sure if there's any way around that problem.

[Lynn Tramper]

Thanks for that tip Brad. I'm not sure how condensation would get into the loft if it is completely sealed with tape..? If you can remember who the poster was or where they posted the issue, I would be most grateful. I have used DAMs for quite some time and never had this problem. Condensation IN the loft would mean that the cuban may be waterproof but is not truly vapour-proof. That hasn't been my experience sleeping in the Refuge-X where all the water vapour was trapped on the inside of the tent. I could make a small sample pouch of taped cuban/down and try a steam test on it. If the vapour is getting into the insulation I should be able to detect this by weighing it before and after (wiping dry the outside). This might be worthwhile before I take on a large-scale project. Maybe I should contact Bill F…

[Bill Fornshell]

I have made all kinds of stuff using all cuben, part cuben, quilts, sleeping bags, rain gear, etc .

I have never had a condensation problem with any of it.

You have to be able to maintain your body temperature at a slightly cool state so condensation for me has never been a problem.

Most people don't have a clue as to how to do this so I stopped writing about what I am doing.

It is the same with a VB items. Almost no one knows how to wear them and seem to have a mental block when it comes to figuring it out.

[Huzefa @ Blue Bolt Gear]

Hi Allison.

I had envisioned a similar idea which uses cuben as inner shell and propore (from driduck poncho) as outer shell.

Since you have given so much thought to this idea I have question for you. Do you think the bag will loft well, and fast, from an opening just in the bottom baffle?

I am not quite sure about the answer. Thats why I was thinking of WPB top.

[Bill Fornshell]

You all might see something in this old thread of mine that might help or give you an idea or two.

Cuben / Pertex Quantum – Down Quilt

[Colin Krusor]

Brad and Allison,

I think it might have been a couple of my posts about condensation that you were referring to. They were part of a discussion with Huzefa awhile ago in a thread that's now pretty well hidden.

I made a cuben mummy bag with 800+ down and 0.3oz row cover for baffles. It was cuben inside and out, and had a cut-off soda bottle top with cap for inflation and deflation, so it was essentially inflatable (a little different than your design, Allison).

I do a lot of my camping on the meadows in the Olympic Mountains, where there is sometimes an unusual combination of high daytime humidity and warm to mild daytime temps with low nighttime temps.

I used a trash bag with outside air to inflate the sleeping bag (not my breath), but the air was so laden with moisture that it condensed in the cool outer layers of the sleeping bag during the night and wet the down. The air temperature in the outer layers of down fell below the dew point. The condensed water had no way out, so a little more accumulated each night. This might not be a problem at all in most areas. I think DAMs don't have this problem (even in my area) because the down is between your body and the ground, which are both much warmer than the nighttime air.

In the other thread I told the story of my attempts to solve this with dessicants. I pumped air through a tube of dessicant into the bag on a few occasions, to try to drive the dew point of the atmosphere in the bag below minimum nighttime temps in the outer parts of the down. It worked, but the dessicant had to be dried each day over my stove, and it became too complicated and fallible for my liking. I also found that the cuben just doesn't resist puncture very well, and isn't practical for anything inflatable.

Your idea of using a breathable panel is better, I think, and might prevent any condensation problem. Warm, humid days followed by cold nights might still produce some wetness in the outer parts of the down, but it would be much easier to dry.

Your idea sounds good to me. I can't wait to see how it turns out.

[Lynn Tramper]

Wow, thanks for that Colin. Lofting has been my biggest concern, and using an inflation bag might just help. I've already got one for the DAM. And yes, I assume that in humid conditions the outside air would introduce moisture into the system…inevitable, but this is true of any lofting system. I would say in conditions such as you experience that down may not be the best insulation.

Bill, I have followed your threads closely, but I don't quite understand the Cuben/Pertex/Silk concept. Is it a "bivy bag" for your silk quilt? It would be reasonably weather resistant under a shelter, but not truly waterproof. The ability to air/loft the inner separately is a sound idea though, and may be the way to go even though it will add weight.

I am familiar with using VBLs, so I'm not too concerned about that aspect of the system. High humidity is not often a big problem for me either, though on occassion it is inevitable… :( After a humid trip with DAMs we make an effort to re-inflate them with a hair dryer full of warm, dry air and leave the valves open to equilibrate with the dryer home air. The same would apply to any cuben quilt I make.

All food for thought.

[Steven Evans]

Allison,
I can't sew so I'm here just for morale support…please make one and show us everything. A 20 oz 4 season quilt would be very impressive.
I currently use a VBL with my winter bag, so any way to incorporate this would be a huge weight savings.

[Huzefa @ Blue Bolt Gear]

>had a cut-off soda bottle top with cap for inflation and deflation

thats a cool idea Colin.

>breathable silk panel
The only problem is that IF you plan to go shelterless i.e. without a bivy, tarp, or tent (I plan to that sometime) then you can get your down wet while inflation/deflation.

To me replacing the top completely or with alternating strips of cuben and propore for weight saving makes more sense for faster lofting and such trips.

[Lynn Tramper]

"The only problem is that IF you plan to go shelterless i.e. without a bivy, tarp, or tent (I plan to that sometime) then you can get your down wet while inflation/deflation."

I must admit I don't INTEND to go completely shelterless, though in an emergency that option would be a nice option (emergencies include not making it to a hut due to a swollen river crossing, injury, etc…. The silk panel would be covered over by a velcro flap of cuben, and would be on the underside of the quilt so somewhat protected, but more and more I am thinking about the idea of just having an inflation port and pump bag as mentioned. In fact, I wonder if a pump bag would allow "over-inflation" which would accelerate lofting?? Hmmmm, the feedback here is great.

[Brad Groves]

Colin, thanks for posting.

Allison, I guess I'm re-intrigued. Keep us posted! I like the idea of the silk end baffle/cuben flap–perhaps even one on each end? Just sitting here thinking as I type, I'm wondering about the liner material you use–ie, with all cuben, inside's (duh) white, so you don't get the solar-enhanced drying… but does that matter?

[Lynn Tramper]

Brad, there would obviously be a market for dark blue or black cuben, but since the fabric won't be absorbing the moisture, I can wipe most of the water off with a towel. I do this all the time in my Refuge-X. It will still be damp, but hopefully not sodden.

I've decided I need to make a mini mock version to test things like lofting, inflating, deflatingetc…It's an expensive project and I want to get it right. I'm also considering making the filled part of it narrower and just use it as a one person quilt. I would keep the total width the same, but the cuben 'wings' would not have down in them. This would weigh less, but still retain ability to pitch as a shelter, or wrap up tight to keep out drafts (more of a top-bag concept).

Since the cuben comes in 48" width, that may be the best size to aim for. This would eliminate any seams over the down compartments. I'll test this width on the weekend to see if it will work for me as a top-bag.

Thanks for all your input.

[Andrew :-)]

Allison,
If you want coloured cuben for solar drying etc, I think Bill did some testing of coloured cuben using dyes. It's in the forums here somewhere.

---

Also, you are in NZ yes?
If you don't mind me asking, where did you source your cuben and what was the cost, any hassle factors etc.
Taped cuben could be a solution to a project i've had on hold for some time – Thanks. Feel free to answer by pm or email as I don't want to tangent this great thread.

---

[Lynn Tramper]

Andrew, I don't think it's too off-topic, as I am going to (note I haven't ordered it yet) get my cuben and tape through Quest Outfitters , an American based company.

I won't order anything until I've finalised my design, as I want to order 'just enough' to do the job. I get my down from Thru Hiker (I've dealt with them many times and there is absolutely no hassle factor other than the usual postage), and I haven't sourced the silk yet.

The cuben I'm playing with at the moment is just the stuff sack from a Refuge-X.

[Andrew :-)]

Thanks Allison,
(I have a Salewa Seirra Leone winter tent with rotting floor/fly that could do with a retrofit and various mods).

Good luck with your cuben quilt/bivvy, keep us updated.

[Huzefa @ Blue Bolt Gear]

I know it sounded a bit confusing. What I was saying had nothing to with the drybag idea.

I was talking about using cuben as outershell and inflating/deflating the quilt. Now if you compress some part of quilt under you while sleeping then it should loft bag as soon as you move away from it. If you were using a full cuben outer shell then you may get up in the middle of the night feeling cold and have to reinflate your compressed bag.

some lw. 2layer GTX or propore would be best if you want a waterproof quilt.

It would be a bit heavy negating perhaps any weight saving from using cuben but I IMO it would be worth it.

[Brad Groves]

Allison- Keep us posted on your mini sample quilt, eh? I just did a trial run with the 8mm silk bag I was hoping to do, and it just won't work for me. So hey, maybe cuben's the way to go!

[Bill Fornshell]

Hi Brad,

Where did you get your silk?

Bill

[Lynn Tramper]

Oh well Hufeza, I still don't understand…do you mean if you use a silk inner bag that is not attached to the cuben outer?? Then yes, the inner bag could move and leave you with a cold spot of just cuben, otherwise I'm not sure what you mean. Since i wish to make the *lightest* quilt possible, I won't be using the silk inner bag method that Bill used, so my down will be fully baffled to the the cuben shell.

[Huzefa @ Blue Bolt Gear]

Yes, you dont need a silk inner bag for a quilt.

But I wasnt talking about cold spot from inner bag moving. If you are using cuben for top how will the quilt loft? You will have to manually inflate it. Now, while sleeping if some part of quilt is under you, it will compress. But it wont loft back quickly since the top is NOT AIR PERMEABLE. So you will get cold spot at the compressed part of the quilt. You will have to then again inflate it.

Got my point?

[Author]

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