My lovely and talented spouse, Dragonfly, whom I love dearly and forever :D made my new ultralight bivy sack this afternoon. She gave up a perfectly good snow day from school to do it, too.

The bivy has a sil nylon bottom, and a top that is Momentum 90 fabric and Nanoseeum mesh from Thru-hiker.com. The zipper runs around the outside edge from the right shoulder down to the left hip for easy access. The bottom and top ends are 'boxed' like a stuff sack, for more room, and it has tie-out points at each corner. We used a #3 zipper with four pulls, so I have several options for getting in and out. I like having mostly mesh over the upper body, for breathability.

I spent the last week trying to teach myself how to sew. Yeah, right. Dragonfly sews flat-felled seams with two very light, slippery fabrics, without using any pins. All the seams are straight and perfect. My pathetic attempts pale before the goddess of the sewing machine. Many thanks for all her help.

The final weight, with a mesh stuff sack, is exactly 8 ounces.

Here are some photos:

Dragonfly cutting out the bottom fabric:
http://whiteblaze.net/forum/vbg/files/2/6/6/bivy0329.jpg

Sewing one of the edge seams:
http://whiteblaze.net/forum/vbg/files/2/6/6/bivy0335.jpg

Attaching the hood to the bottom fabric:
http://whiteblaze.net/forum/vbg/files/2/6/6/bivy0336.jpg

Dragonfly inside my winter bag -- a Western Mountaineering Antelope, testing out the bivy. It's a little big for her, but fits me just fine:
http://whiteblaze.net/forum/vbg/files/2/6/6/bivy0345.jpg

Interesting... What's the purpose of the mesh- doesn't that defeat the purpose of the bivy?

Joe Hiker,

No, this is *not* a waterproof bivy. It's a breathable bivy with a DWR top fabric and mesh. It's made for use under a tarp. It keeps the bugs off, keeps me on my pad, and adds a significant amount of warmth (by reducing convective heat loss). I've been using one like this for about 8 years -- the old Mountain Hardwear Micro Mesh bivy -- but the old one is not large enough for my winter bag. Plus it weighs 16oz.

I like this style of bivy on the AT. I can use it under a tarp, or in a shelter, or out under the stars. It replaces my ground sheet, and thus only adds a little in overall weight to my pack. And it keeps the mice from running across my face in shelters. I suspect it would also work on other trails.

You can buy this sort of thing from BackpackingLight and Oware, but they will run you over $200. This was made for about $60 in materials.

Cheers,
--Ken

Ken,

Give my complements to your wife!

It looks great, and VERY functional. I want one!

Looks like a nice piece of gear.

Question, how does the Momentum90 fabric feel? Does it feel like regular sleeping bag nylon, or more of the softer feel that other taffeta has?

One of these days I am going to be making a couple of down quilts. I like the softer feel then the normal ripstop plastic feel.

I like it- it looks very professional..give the compliments to your wife.

I love the color.:)

I've never used a bivy, but I would think that the exposed mesh chest would let out a lot of heat, thus negating most of the point of the bivy.

What would be tits would be a full bivy with a full fabric top, that you could unzip the chest portion to expose no-seeum mesh like you have- the extra fabric for the chest wouldn't add much weight, and would make it that much more versatile.

just thinking out loud here, but good job!

did you follow a pattern or make one yourself?


I made something like this for my hammock. Basically a 3/4 DWR and 1/4 noncoated bivy shaped thing (hammock sock/travel pod) to enclose my hammock. I measured a 15-20 degree difference inside to out in the cold when I close it. The uncoated is on top to vent my body mosture.

Boston -- the mesh holds in a surprising amount of heat. Not as much as the fabric, but more than expected. Plus I like the ventilation in warm weather, when I need the mesh for bug protection.

H.E. -- the Momentum 90 feels a lot like Pertex Quantum. Like the shell fabric on some of the high-end UL bags. It is single-calendared, so it's shiny on the 'wrong' side. It's very light, which is the whole point, of course. We'll see how breathable it turns out to be. According to AYCE at thru-hiker, it has much better DWR than the 1.1oz ripstop that I've used.

The bivy is just great. It does look very professional, which is way better than what it would have looked like if I had made it myself. You should see my test samples, where I was trying to sew a simple felled seam. Ugly. Maybe I can talk Dragonfly into making a set and selling them. (Right, like she needs something else to do in her copious free time.)

Thanks for all the comments.
~Ken

did you follow a pattern or make one yourself?



Let me follow up on this and answer some of the mesh questions at the same time. I didn't pull this idea out of thin air -- I have been using the commercial version of this bivy for 7 or 8 years. If you went through Neel Gap in the late 90s or so, Walasi-yi had a rack of the Mountain Hardwear Micro Mesh bivies on the wall, and sold a ton of them. (At a pound apiece....) For me, this bivy style works well with my own personal hiking style.

So the pattern itself was simple to make -- it's just a coffin-shaped pattern top and bottom. We made it ourselves out of banner paper. I had to significantly increase the chest girth to accommodate my winter bag. It got a little tricky with the zipper around the hood area, since I wanted the zipper to go around the outside edge -- but the edge was boxed' to give it some depth. So there is a piece of the M90 fabric sewn to the bottom sil, then boxed, then we cut a freehand curve in that fabric before attaching the zipper. Dragonfly was able to figure out how to do this in three dimensions, and get the zipper working properly, and looking good at the same time. Way beyond my abilities.

You can buy bivies made from similar materials, but none with the full mesh upper body and the perimeter zipper. That's strictly a make-your-own project for now.

Ken,
that is gorgeous! compliments to Dragonfly.

My compliments to you for design and DragonFly for the excellent seamtress work.

very nice indeed.

bigcranky, my compliments to dragonfly. very nice bivy.
does she sew tarps and snakes skins:D:D:D:D

you are very lucky!

[quote=bigcranky;314711]My lovely and talented spouse, Dragonfly, whom I love dearly and forever :D made my new ultralight bivy sack this afternoon. She gave up a perfectly good snow day from school to do it, too.

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Great job ! What did it end up weighing ?

I'm not as talented, I own the OR Bug Bivy, which is close in appearance and has a small arch pole that keeps the mesh off my upper chest/head area.

I also bought the Equinox Silnylon Bivy. No mesh, but I may end up adding some venting depending on how much condensation I get.

'Slogger

Thanks for the comments, everyone; I know Dragonfly will read them. Footslogger, the bivy ended up at exactly 8 ounces in its little mesh stuff sack. We had an OR Double Bug Bivy a few years ago, and never used it. Similar concept, though.

Thanks for the comments, everyone; I know Dragonfly will read them. Footslogger, the bivy ended up at exactly 8 ounces in its little mesh stuff sack. We had an OR Double Bug Bivy a few years ago, and never used it. Similar concept, though.

=======================================

Wow ...that's light. Even lighter than the single OR Bug Bivy. By the way, we have the OR Double Bug Bivy too. My silnylon bivy from Equinox is about 6.5 oz and has a half zipper. Bet if I cut out some of the silnyon and added noseeum mesh I could get it down even lighter.

Wish I knew how to sew. Guess I could learn !!

'Slogger

My lovely and talented spouse, Dragonfly, whom I love dearly and forever :D made my new ultralight bivy sack this afternoon. She gave up a perfectly good snow day from school to do it, too.
Here are some photos:

Dragonfly cutting out the bottom fabric:
http://whiteblaze.net/forum/vbg/files/2/6/6/bivy0329.jpg

Sewing one of the edge seams:
http://whiteblaze.net/forum/vbg/files/2/6/6/bivy0335.jpg

Attaching the hood to the bottom fabric:
http://whiteblaze.net/forum/vbg/files/2/6/6/bivy0336.jpg

Dragonfly inside my winter bag -- a Western Mountaineering Antelope, testing out the bivy. It's a little big for her, but fits me just fine:
http://whiteblaze.net/forum/vbg/files/2/6/6/bivy0345.jpg

That looks really nice. I bet she could make some good extra income if she wanted to sew these kind of things on a part time basis.

;)

I'd like to have something like that but with the silnylon extending up further on the sides in the mesh area. Sort of a cowboy camping groundsheet bugbivy. Or really good for under a very small tarp.

Way to go Dragonfly. :)

I like it- it looks very professional..give the compliments to your wife.

I love the color.:)

I've never used a bivy, but I would think that the exposed mesh chest would let out a lot of heat, thus negating most of the point of the bivy.

What would be tits would be a full bivy with a full fabric top, that you could unzip the chest portion to expose no-seeum mesh like you have- the extra fabric for the chest wouldn't add much weight, and would make it that much more versatile.

just thinking out loud here, but good job!

did you follow a pattern or make one yourself?

If you are looking for a pattern, Six Moons has one a lot like this that you can D/L from their site.

http://www.sixmoondesigns.com/ultralight/myo_Meteor.asp

I'm thinking of making something similar. I know you made this a while ago, but do you remember some of the dimensions of your fabric? Or even just the dimensions of the finished product?

I'm toying with the idea of having a zipper across the chest (for simplicity's sake, unfortunately we all don't have a dragonfly around).

Did you have any problem attaching the no-see-um to the other fabrics?

Again, awesome bivy.

I'm thinking of making something similar. I know you made this a while ago, but do you remember some of the dimensions of your fabric? Or even just the dimensions of the finished product?

I'm toying with the idea of having a zipper across the chest (for simplicity's sake, unfortunately we all don't have a dragonfly around).

Did you have any problem attaching the no-see-um to the other fabrics?



Thanks. We made a pattern from paper to cut the top and bottom fabric to the same size. The pattern is coffin-shaped, and larger than my sleeping bag to account for the three-dimensionality of the finished product. My pattern is 92 inches long, 40 inches wide at the shoulder, and 32 inches wide at the feet. Remember that we made this for a big guy in a huge winter sleeping bag. The finished product is very large.

Cutting the bottom fabric is easy -- just lay out the silnylon on the pattern and cut. The top was harder - we had to sew the Momentum 90 and the mesh together first, then lay that out on the pattern, lining up the seam so it was in the right place on chest area.

Not sure about the zipper. I know the chest zipper is traditional, but I find those make it *very* hard to get in and out of the bivy. I think if you can sew the top and bottom fabrics together, adding the circumferential zipper wasn't all that much more difficult. (Ha. I say that when it was my lovely wife who did all the sewing. I can't stitch a straight line.)

The no-see-um was actually pretty easy to work with. The silnylon and the Momentum 90 are both very slippery, thin fabrics that I cannot even begin to work with. Watching Dragonfly sew up the major seams was pretty impressive.

BignCranky: wow, as you have replied to my bify sack thread this is great. I wish I had found this before. Very nice looking. I like it and the large area of noseeum will be good for air flow.

Thats sweet! I would pay money for one of those! Something like that could fund your trips. If i tried to sew something like there would be alot of swearing, alot of redos, and i am sure some blood!! Kudos to the wifey!

That looks like a great bivy... great craftmanship!

Hey, thanks a lot for the dimensions and tips. I'm just waiting on the materials to arrive, and trying to design a pattern on paper. I'll probably design something significantly smaller (I'm 5'7", no winter bag). But, I'll definitely take the chest zip tip into consideration. It seems like it might be a little difficult to get out. I'll have to let you know how/when it turns out. Thanks again.

I really like this bivy, with the 3/4 nylon 1/4 noseeum concept. Good with poncho/tarp.

nice, im in the process of making a bug bivy out of some scraps of tyvek i pulled from a dumpster right now.

Wow - you are a lucky man. That is super nice - reminds me of the meteorlite. That is the perfect cool/warm weather design.

that's worth 200 what were the $ materials? looks like another cottage industry for someone

Beautiful work - how much you want for one! I'm serious!

Following your rough design, I just finished sewing my bivy today.
I spent about $85 on materials from Thru-hiker, and came out with a bivy weighing just under 5oz. Spinntex bottom, Momentum MR top, and Nano-seeum head area. I'm going to try to test it out tonight. Thanks again for your help.

Following your rough design, I just finished sewing my bivy today.
I spent about $85 on materials from Thru-hiker, and came out with a bivy weighing just under 5oz. Spinntex bottom, Momentum MR top, and Nano-seeum head area. I'm going to try to test it out tonight. Thanks again for your help.

Jaani- please post a report after you've used the bivy, I'm also interested in making one and using Spinntex for the bottom,

I say tested, but conditions weren't too crazy, I was hoping for a little more precipitation. That being said, it was mid-twenties through the night with 20-25 MPH winds. The ground was moist but not so much that it would gush or soak through sneakers when walking. As expected, no water leaked through the Spinntex. The wind was noisy on the Spinntex, but the sides of the bivy (bathtub-esque) blocked a significant amount of the wind. The Momentum/Nano-see-um topped allowed any moisture to escape, so there wasn't any condensation.

I'm impressed with the materials and weight. I'll be using them with a sil-nylon tarp on a thru-hike in a few weeks.

I find other people's postings to be super helpful when making gear, so any questions I'd try to answer, I'm a beginner myself.

something I never said bivy -camping "I hoped for more rain" take orders at 200$ they get that on backpacking light -I paid it

Jaani,

Thanks for the feedback. I just showed it to Dragonfly, and she appreciates the comments. We appreciate the comments on selling the bivy, but I think she has enough work on her plate right now.

Jaani, did you use this bivy under a tarp? If so, what size tarp? Was the top fabric exposed to direct rain? I've had some significant side-splash under my 6x10 tarp, which the Momentum fabric handled easily, but never any direct rain.

Well, the precip was snow, not rain. So I haven't had any side splash yet. I did spill a little bit of water from my bottle which beaded up and ran off no problem. But, yeah, I was under a 6x10 tarp as well. Night time temps here in Western NY are still dropping below freezing. I might not encounter any rain until I hit the trail. Later.