Bivy + Cuben Fiber/Down Quilt

I've been using my cuben down quilt with a bivy bag that has a cuben bottom and momentum top. Works fine.

Same here as Lynn.

Yep, same here. No problems.

Yet another with no problem combining the two.

All right. Next question then. What bivy sack should I get. I'm think the new BPL bivy (when available). What do you use.

It depends on what you expect out of your bivy.

I use a Tigoat bivy with side zip and net hood. Eventually I'd like to make my own bivy with dual side zip and a deep hood net…hopefully I can cut a few grams and get a bivy that's breathes better.

Either a TiGoat bivy, an MLD Superlight or an Oware bivy would be great choices. My personal preference is the MLD.

What Doug said!

MLD +1

Half moon net window or net only hood? Do I need the extra ventilation of the net only hood or will I perfer the standard net window? What do you use?

I have one of each — but if I was to only get one I'd get the half moon window. Net only hood is really for very warm weather.

Pictures Lynn pictures!!!

I know you asked Lynn, but here's some of my setup. Cuben Fiber/Momentum Bivy with my Cuben quilt inside.

Steven's bivy looks pretty much the same as mine.

Steven did you make your own bivy?

Hey Justin,
The bivy in the picture is the one my mom made for me a couple of years ago. Of course, you can buy one on my website now (shameless self promotion).

Suluk 46 – CR Bivy

Don’t worry, my mom doesn’t sew these ones :) I hired a seamstress.

Insanity! How did I miss that new item Steve? That looks like a stellar bivy. 2.9 oz.? Unreal and very cool. I love your stuff.

Yeah, they're pretty cool. Mine also comes in at 2.9 oz. At that weight I even take it on day trips for emergency purposes (mine's home made). Combined with a cuben quilt you have a pretty awesome light weight system to keep the elements at bay and keep your quilt tucked in. My quilt: 12.7 oz; my balaclava: 1.5 oz; bivy bag: 2.9 oz. That's 17 oz for a system to keep me warm well below freezing :)

Okay, I am really intrigued about your systems. Some questions:

– The quilts are pretty much water proof and non-breathable. I have plenty of experience with vabor liners. How to you feel your quilts do in regard to perspiration and internal condensation. Does the quilt construction make it easy to vent, does your body automatically vent if needed, or do you wake up. Or is it a non-issue?

– I assume the only function of the stripe on Marshall's designs is to help loft the quilt, meaning that even though the sewing thread points are not-water proof, but not enough to help lofting it.

– If the quilt is indeed nearly water proof, why would you need a bivy. Seems that a little spray or spindrift would not affect the quilt at all, and even a small tarp would be adequate protection.

– If the bivy is needed, does it cause any condensation at all? It seems that some moisture/vapor would get through the sewing.

– This one is subjective. How much loft do your quilts have (inches), and what is the coldest temperatures that you have slept in without needing to supplement with insulated clothing.

– What if any (there must be some) downside is there to your quilts, other than the obvious potential abrasion. Do you feel you will get as much life out of it, as some of the "conventional" high quality quilts many of us own.

– If I were to order on today, would you request any special features, such as extra down in footbox, wider footbox or top, the DWR stripe, no strip, special straps, cords, etc.

– Steve, I believe you do not use a ground sheet, only one of your sleeping pads. Does the cuben "stick" to the pad, or does it have a tendency to by slippery? I like your idea of replacing a ground sheet with a full size 25" wide pad.

– Anything else you think would be appropriate to comment on?

With regards to my system (a non-momentum striped one), there is a lengthy discussion here:

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=31690

As far as the bivy bag goes, for me it is more to stop drafts and add a bit more warmth, but it is also possible for water to enter the quilt through the stitching lines.

Thanks, Lynn. Now I remember reading that thread. Answered most of my questions. Looks like I need this more than my wife needs the new dishwasher :)

Hey Nick,
I'll quickly answer a few questions as I know you stated that the other thread cleared most things up.

I don't have an issue with internal condensation. I wanted the VB effect when we were designing it, and it is something I am used to. I do notice some moisture (clamminess) in the footbox sometimes, but Tim now keeps all the footboxes open (mine is closed) so venting is easier. I don't really vent all that much, it's kinda natural now so I just sleep away…

I use a bivy for the same reasons Lynn does. Helps keep wind off me, and I usually have a few pieces of clothing/gear under and around me so it helps them from being pushed out in the open.

I'd have to measure the loft of mine, I can't remember off the top of my head, but my quilt can keep me warm to around freezing wearing just a baselayer. It has 8 oz of down and gets quite puffy.

In all honesty, the quilt feels (IMO) tougher then you would think. My tarp which is made of the same weight cuben feels weak and flimsy but the quilt gives the impression that it is thicker. Why? I have no idea. I do treat it very nicely and short of a disastrous accident, I see now reason why it would not last me years. Worst case scenario, I'd need to do a repair.

Hmmm, changes if I were to order again…I'm pretty happy. I'd make sure Tim puts the button and cinch cord on the top opening to close it up tight. I love that thing! I removed the elastics that run under me, but that is more preference than anything else. Sorry man, it's good as it is. :)

I just took a trip to the garage, the cuben definitely "sticks" to the pad. It will move, but it's like a static cling a bit – tacky – that make sense?. Definitely not slippery like on a silnylon floor.

OK, hope that helps you out a bit.

Thanks, Steve.

That helps a lot.

@ Steve: I just stitched up a mock-up of a bivy I want to make this morning. It is a cross between the new BPL Vapr and yours ,single outside seam, two zippers and mesh (think light & luxurious). If my calculations are correct with a .48 Cuben it should weigh 4.89oz. Where do you get your material (Cuben & Momentum) from.

Cuben can be bought from Quest Outfitters, Zpacks or even directly from the source at Cubic Tech.

Thru Hiker is the only place I know that sells Momentum.