Oct 14, 2009 at 9:52 pm #1240265
Hello to all fellow hikers….
Well, my beautiful and wise girlfriend just bought a sewing machine, hell yeah. So, its time to do some sewin'. Eventually I want to make a nice homemade tarp, but don't have the confidence yet. So i am going to start out by making a bivy sack.
I am familiar with some designs for a bivy sack, ie bathtub or just two identical pieces sewn together.
I was thinking about creating a cylinder type shape for a sack. Sew a tube together big enough for your bag plus alittle more for the loft of the bag and then sew a circular piece to the bottom. It sounds simple enough. Im curious that I haven't seen the type of design in other sacks. Make sense to me, fewer seams. I am just curious if there are any huge disadvantages to this designs. I was wondering if anybody has tested this designs. I am worried about the condensation, though fabric choice might take care of that problem.
I just want to make a solid, easy, simple bivy. Is the cylinder design totally a bad idea or what?
I apperciate the feedback
Thanks to all. And to all a good nightOct 14, 2009 at 11:41 pm #1536512
The only issue I see is whether to make it breathable or waterproof. Using one piece of fabric will only let you choose one. Adding just one more seam, down the other side, lets you;
Have a waterproof floor and breathable top
Easily taper the shape from shoulders to feet
Increase your girth from 58" up to 116" if you like
Use simpler shapes in cutting
Having said all that, if you try it as a tube, and then decide it isn't great, just unpick the seam, and use your fabric as either the top or the bottom of your new design.Oct 15, 2009 at 7:56 pm #1536867
Excellent point. I apperciate your feedback. That seems to be the norm with bivy sacks, waterproof bottom, breathable top. I imagine it is still possible to do the tube design with two different types of fabric with some creative sewing.
Can anyone think of any other disadvantages to the tube/cylinder design.
I am not opposed to the other designs on the market. I kinda just want something different, maybe original.
Thanks to all.Oct 16, 2009 at 2:00 am #1536944
If you add that extra seam in, there's absolutely no reason not to go ahead and use your tube design.
If you haven't used a bivvy before, consider picking up "The Book of the Bivvy" by Ronald Turnbull. http://www.bookdepository.co.uk/ offers free worldwide shipping, and has it in stock.Oct 16, 2009 at 2:07 am #1536949
@mikefaedundeeLocale: Under a bush in Scotland
You could make a one seam 'tube', or tapered 'cone', if you made the bivvy totally from a W/B fabric like Event.Oct 16, 2009 at 10:08 am #1537000
@crgowoLocale: Desert SW
where can you buy event fabric?Oct 21, 2009 at 2:52 am #1538373
I think you will have a real hard time finding Event. I would probably go for epic. You can try these guys:
They seem to have a pretty good range of materials at a reasonable price. Good luck.
P.Oct 21, 2009 at 7:02 am #1538401
@crgowoLocale: Desert SW
Thats what I thought but since Mike mentioned making it from Event I was wondering if he knew where to get some.Oct 21, 2009 at 8:29 am #1538418
@ramblerLocale: On the AT in VA
Momentum .09 is a nice breathable top from thru-hiker. Nice color choices, too.
Maybe you could not sew the one tube seam on your WP fabric all the way up, maybe only half way, or slightly less than half way. It could be used with the opening on top or on the bottom. You could add a few ties so it could be tied together if you wanted to close it. It would leave you with ann option for venting.Oct 21, 2009 at 1:11 pm #1538497
Franco DarioliBPL Member
Most fabric is available up to 60" wide. Are you sure you can get this kind of fabric 80" or so wide ?
FrancoOct 25, 2009 at 7:18 am #1539470
James D BuchBPL Member
Your suggestion to pick up "The Book of Bivvy" by Ronald Turnbull was excellent.
I greatly enjoyed it, and learned quite a few things.
JimOct 25, 2009 at 6:14 pm #1539624
I'm glad you enjoyed it. I liked it so much I had a copy sent out to a friend. It's convinced him to ask for a bivy as a Christmas present from his wife and kids.
Turnbull does have the true UL spirit, including his ideas on ducking out for a 24 hr trip.
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