Page 1 of 4 123 ... LastLast
Results 1 to 10 of 33
  1. #1
    Senior Member schrochem's Avatar
    Join Date
    Jun 2007
    Location
    Austin,Tx
    Posts
    796
    Images
    57

    Thumbs up Bridge Hammock Adjustable Insulation

    Hello Hangers!

    I hope many are following the discussion on the 'Bridge' Hammock
    http://www.hammockforums.net/forum/s...ead.php?t=1297

    I personally believe this is going to be quite a ride and open new doors to enjoy hammock camping. It got me quite excited and I now have a working prototype. The beauty of the design really allows a whole new way of thinking. Today I was working on a completely different approach to using a bugnet but after sewing and ripping and sewing and ripping I decided to work on something else.

    A month or so ago I had been reading the archives of the yahoo hammock camping group. I had been reading up on insulation and became intriqued by two things. First was reading about 'opening the windows' of underquilts and second was Youngblood's post here:
    http://groups.yahoo.com/group/hammoc.../message/17113

    Specifically this paragraph
    "In general, non-breathable is best in cooler and windy conditions
    while breathable is best in warmer and static conditions. We can
    either adjust the breathability of our insulation or live with what we
    chose when the conditions are not optimum for what we chose. You can
    have insulation that you swear by in the right conditions, swear at in
    the wrong conditions and it works okay in most conditions... and that
    is not all that uncommon. "

    This got me to thinking about some sort of adjustable system (that you dont' have to get out of the hammock). Later that week I was eating lunch and noticed some blinds over the windows. You know the type you can lower or raise and/or open the individual louvers. So the noggin just kept on grinding away with all this information. I wanted some sort of system you could reach up and pull or let out a cord to adjust the insulation below you. Well with my HH and my DIY speer, the cuts etc. make that kind of difficult. Enter the Bridge style hammock!

    First of all this is easy!!
    Basically when you make the hammock itself you can cut another piece of fabric the same size. Basically this is going to go under the hammock like a second layer. Oh and please don't eye the sewing!!! this is prototype work and the black is a previous version that got ripped up


    Here you can see how the ends meet


    Now in this photo you can see the red line just above the piece of wood. That's were the two ends from the second layer meet. Then the line feeds through the buckle/ring and back down the ridgeline toward the middle.


    I will be coming up with a better system to pull both cords at the same time,but to test functionality I just used these cord locks


    Okay so it all looks fine and good but what's it do?
    Well, you can adjust the height of your insulation. Here the 'windows are open'


    Now let's close those windows


    So to open and close the windows, I just have to use the lines coming to the center!
    What's cool about this is you can put anything you want down there. I was thinking about putting my summer quilt in there. As you can see in the pictures above I have my BA insulated air core in there. Well inside the hammock I hated it. But in the second layer, I can get in the hammock, lower the bottom (if it isn't already) and reach below to make sure the pad is in the right place. Then just pull up the bottom.

    Another great thing is weight. You can use any fabric you want because this isn't load bearing. I will probably use 1.1 ripstop and the lightest cord I can find. The shape of the fabric means no waste and it isn't much fabric to start with. For me this will be my bottom protection from bugs (instead of a full bugnet), I'll just have a double layer. BUT it's completely removable.
    To add a little warmth, I might use a thin layer of primaloft down there just to keep the chills down. OR I might cut a neat sheet in this shape and use it!

    Okay, so the other thing I was concerned with was what Youngblood said in the post linked above "In general, non-breathable is best in cooler and windy conditions while breathable is best in warmer and static conditions."

    So I was thinking there could be more than one layer. The first layer could be breathable and a second layer non-breathable. Add your insulation for the range your going for and then you can adjust accordingly. You could start out with the windows all the way open, then maybe shut the breathable window with some medium insulation and if it gets bitter cold and windy you could close the outside window with heavy insulation and non breathing fabric.
    Think of them overlayed like these tarps (but upside down) (photo compliments of OES)
    http://www.outdoorequipmentsupplier....20compare1.jpg

    Making your own underquilt for this would be super easy. You have the exact shape of the hammock! To save weight you could alos just insulate where you want (the bottom and a little up the sides).

    Another thing that can be done is to close in the ends. When cutting the shape just leave some extra fabric on the end so you can fold them around.

    In working through this I know I'll need to adjust my next prototype. I'll be using the rings at ends of the fabric like Tee Dee did
    http://www.hammockforums.net/gallery.../6/010_016.jpg

    This will serve several purposes, but for this adjustable bottom layer it will provide a place for the lines to run through. Right now I have too much friction.

    I'm sure this will evolve as I play with it and hopefully as others get involved but to me these are exciting times
    Scott

    "Man is a stream whose source is hidden."
    RWE

  2. #2
    GrizzlyAdams's Avatar
    Join Date
    Apr 2007
    Location
    Illinois
    Hammock
    DIY Bridge, v0.n, where n is large
    Tarp
    depends on season
    Insulation
    DIY UQ
    Posts
    4,628
    Images
    564
    Scott--that's clever.
    I've been looking at the pictures you and TeeDee posted, and I get the impression that the ridgeline is mighty high relative to the prone occupant. Doesn't look like lying on your back you can reach up and touch it.

    The main role of the ridgeline is to control the flatness; given the height of the spreader bars above the floor of the hammock, the method of attaching the ridgeline to the suspension rings will always make that very high. This does not have to be the line accessable to the occupant.

    It seems to me that you could run a separate utility line from spreader bar to spreader bar, for hanging things you want near at hand in the hammock, and this could be a place where you thread your underquilt control line. Might also be a place to support the top of the bugnet, rather than also running that all the way up to the flatness control line.

    Depending on the spreader bars, you could try to make this lower line the flatness control line as well, although centering could be an issue. A finesse to this would be to have two flatness control lines, extending on each side from the endpoints of the spreader bars. This would not put undo force on poles, but would make getting in and out over the side a bit trickier.

    just some thoughts,
    Grizz

  3. #3
    Senior Member blackbishop351's Avatar
    Join Date
    Oct 2006
    Location
    Greensboro, NC
    Hammock
    Homemade Speer-type
    Tarp
    BlackCat
    Insulation
    Potomac UQ
    Posts
    1,564
    Images
    59
    I feel the need to butt in a bit here, even though I'm not really involved or interested in this hammock design (I'm perfectly happy with my Speer-type). Reason being, the quote posted here from Youngblood.

    IMO, sleeping material should NEVER be non-breathable. Why? Because perspiration, to whatever degree, is how your body regulates its temperature. This is true even in cold weather, and it's impossible to provide the PRECISE amount of insulation you need every time. So what happens in cold weather if you over-insulate a bit? In the middle of the night you get too hot. You sweat, but the sweat can't evaporate properly so you keep sweating. In addition, the moisture builds up inside your non-breathable material. Soon you're overheated to some degree and damp. Then suppose you roll over, move around, or need to go to the bathroom. In the right (or wrong?) conditions, you now have the makings of a hypothermic situation. Not good. On the other hand, if your system breathes properly, you allow your body to properly cool itself AND allow excess moisture to leave. Possible disaster averted.

    Anyway. Just my thoughts. The only reason I interjected here is that I'd hate to see people innocently hitting the trail and getting hurt. Just a personal hangup (hey, there's a pun! ) I guess.
    Last edited by blackbishop351; 07-05-2007 at 06:34.
    "Physics is the only true science. All else is stamp collecting." - J. J. Thompson

  4. #4
    slowhike's Avatar
    Join Date
    Oct 2006
    Location
    Winston-Salem, NC
    Hammock
    DIY, gathered end , w/ spreader
    Tarp
    DIY w/ pull-outs
    Insulation
    DAM/ HG Incubator
    Suspension
    Webbing & rings
    Posts
    10,596
    Images
    319
    Quote Originally Posted by blackbishop351 View Post
    I feel the need to butt in a bit here, even though I'm not really involved or interested in this hammock design (I'm perfectly happy with my Speer-type). Reason being, the quote posted here from Youngblood.

    IMO, sleeping material should NEVER be non-breathable. Why? Because perspiration, to whatever degree, is how your body regulates its temperature. This is true even in cold weather, and it's impossible to provide the PRECISE amount of insulation you need every time. So what happens in cold weather if you over-insulate a bit? In the middle of the night you get too hot. You sweat, but the sweat can't evaporate properly so you keep sweating. In addition, the moisture builds up inside your non-breathable material. Soon you're overheated to some degree and damp. Then suppose you roll over, move around, or need to go to the bathroom. In the right (or wrong?) conditions, you now have the makings of a hypothermic situation. Not good. On the other hand, if your system breathes properly, you allow your body to properly cool itself AND allow excess moisture to leave. Possible disaster averted.

    Anyway. Just my thoughts. The only reason I interjected here is that I'd hate to see people hitting innocently hitting the trail and getting hurt. Just a personal hangup (hey, there's a pun! ) I guess.
    BB... if you click on the link to the whole post youngblood made on the hammockcamping yahoo group, you'll get a bigger picture of what dave was talking about.
    at first he's talking about sleeping on a ccf pad, then the hh super shelter, then the tarp tent he made. but he also talks about the need to vent so moister can escape/evaporate.
    but maybe we should start another thread about the pros & cons of non-breathable shells & shelters<g>. ...tim
    don`t leave the CREATOR out of the creation!

  5. #5
    Senior Member schrochem's Avatar
    Join Date
    Jun 2007
    Location
    Austin,Tx
    Posts
    796
    Images
    57
    Quote Originally Posted by GrizzlyAdams View Post
    Scott--that's clever.
    I've been looking at the pictures you and TeeDee posted, and I get the impression that the ridgeline is mighty high relative to the prone occupant. Doesn't look like lying on your back you can reach up and touch it.

    The main role of the ridgeline is to control the flatness; given the height of the spreader bars above the floor of the hammock, the method of attaching the ridgeline to the suspension rings will always make that very high. This does not have to be the line accessable to the occupant.

    It seems to me that you could run a separate utility line from spreader bar to spreader bar, for hanging things you want near at hand in the hammock, and this could be a place where you thread your underquilt control line. Might also be a place to support the top of the bugnet, rather than also running that all the way up to the flatness control line.

    Depending on the spreader bars, you could try to make this lower line the flatness control line as well, although centering could be an issue. A finesse to this would be to have two flatness control lines, extending on each side from the endpoints of the spreader bars. This would not put undo force on poles, but would make getting in and out over the side a bit trickier.

    just some thoughts,
    Grizz
    Good points Grizz. I tried to bring the ridgeline down lower, but the forces on the spreader bar increase as we discussed. However, it's not really that high and if you situp it's easily accessible. Granted, laying down I can barely touch the line.
    The only problem with running a utility line from spreader to spreader, is that the spreaders disappear during packing
    However, it there is a 'sheath' of some sort this could be doable. Perhaps a line could be made from the sheath to the buckle, then you could have the utility line a little above the spreaders, from line to line.

    I was thinking a line could be run across the head end to hang stuff from.
    Scott

    "Man is a stream whose source is hidden."
    RWE

  6. #6
    Senior Member schrochem's Avatar
    Join Date
    Jun 2007
    Location
    Austin,Tx
    Posts
    796
    Images
    57
    Quote Originally Posted by slowhike View Post
    BB... if you click on the link to the whole post youngblood made on the hammockcamping yahoo group, you'll get a bigger picture of what dave was talking about.
    at first he's talking about sleeping on a ccf pad, then the hh super shelter, then the tarp tent he made. but he also talks about the need to vent so moister can escape/evaporate.
    but maybe we should start another thread about the pros & cons of non-breathable shells & shelters<g>. ...tim

    Yes, I probably shouldn't have quoted out of the whole post. Dave goes into the different situations and the potential problems. These 'problems' all seemed to relate to have to adjust the setup. So that is why I think this system might be of use, you can adjust it without getting out of the hammock.
    The variables here are what to use as insulation and I agree that is going to take some time to figure out and it might take some time in different conditions, etc.
    I threw that example out there, but yes there could be an issue with using a non-breathable shell. Perhaps, like the HH supershelter, the outer layer could just be nonbreathable without any insulation. Except here you can adjust it. Perhaps you would never want to fully close that layer, so you could make it bigger and always allow a nice gap between it and the breathable insulation above it. That would give you wind protection but allow breathability.

    I just think that if you have a customizable system that you can control within the hammock that you have endless options to work with. If it works properly, you should be able to control warmth, airflow, wind protection, etc. and of course there is always a better way to do something. So perhaps this will lead to someone coming up with a better system.

    I can't help but invision a bunch of color coded lines and a hanger pulling on them like a crazed scientist in a time machine or something
    Scott

    "Man is a stream whose source is hidden."
    RWE

  7. #7
    Senior Member Just Jeff's Avatar
    Join Date
    Oct 2006
    Location
    Charlottesville, VA
    Hammock
    Blackbird
    Tarp
    MacCat Standard
    Insulation
    Winter Yeti, MWUQ4
    Suspension
    Whoopie Slings
    Posts
    8,012
    Images
    32
    I doubt sil gives much more wind protection than breathable DWR. DWR is pretty hard to blow through even in a concentrated area, so I bet not much wind gets through. Windsuits are made from DWR.

    Having an extra layer of material with an air gap between that layer and your insulation will make you much warmer, too. Like a hammock sock.
    “Republics are created by the virtue, public spirit, and intelligence of the citizens. They fall when the wise are banished from the public councils because they dare to be honest, and the profligate are rewarded because they flatter the people, in order to betray them.” ~Judge Joseph Story

    - My site: http://www.tothewoods.net/
    - Designer, Jeff's Gear Hammock / Pack Cover by JRB

    IMPOSSIBLE JUST TAKES LONGER

  8. #8
    GrizzlyAdams's Avatar
    Join Date
    Apr 2007
    Location
    Illinois
    Hammock
    DIY Bridge, v0.n, where n is large
    Tarp
    depends on season
    Insulation
    DIY UQ
    Posts
    4,628
    Images
    564

    more on ridgeline

    Quote Originally Posted by schrochem View Post
    Good points Grizz. I tried to bring the ridgeline down lower, but the forces on the spreader bar increase as we discussed. However, it's not really that high and if you situp it's easily accessible. Granted, laying down I can barely touch the line.
    The only problem with running a utility line from spreader to spreader, is that the spreaders disappear during packing
    However, it there is a 'sheath' of some sort this could be doable. Perhaps a line could be made from the sheath to the buckle, then you could have the utility line a little above the spreaders, from line to line.

    I was thinking a line could be run across the head end to hang stuff from.
    I worked up another figure before you posted, will share anyway.

    I wondered if when you split the spreader after shortening the length of the line from spreader to suspension rings, you were trying to lower the ridgeline. The diagram in the attachment explains how you could control the length of the ridgeline independently of the suspension. This is looking at the hammock from above. Rather than have two ridgelines from spreader bar end to spreader bar end, you make those connections but then run them to a center line. The forces on the ridgeline (recall TeeDee's analysis) aren't that large. With strong cord you could tie knots and avoid the added weight of more rings. This in turn lets you extend the length of the lines from spreader to suspension rings all the way to the tree if you like, just using enough webbing around the tree to let you tighten things up comfortably. The long lines here reduce the compression force on your spreader----which might be of interest if that spreader is your hiking pole and you didn't remember to bring a spare

    of course, you guys have the real deals to play with, and all I've got is powerpoint. Have at it, and don't mind the peanut gallery.

    Grizz
    Attached Images Attached Images

  9. #9
    Senior Member schrochem's Avatar
    Join Date
    Jun 2007
    Location
    Austin,Tx
    Posts
    796
    Images
    57
    oops, I forgot to add something. When I was originally thinking about this system, I was relating it to our hiking clothes. When the conditions are changing, we layer. So I figured this gives us the same flexability.
    Also, this system isn't only for the Bridge hammock. It's just easier to make the thing work. I had been trying to make it work for a HH or speer (in my head) but the shapes were prohibiting a proper picture.
    Scott

    "Man is a stream whose source is hidden."
    RWE

  10. #10
    Senior Member schrochem's Avatar
    Join Date
    Jun 2007
    Location
    Austin,Tx
    Posts
    796
    Images
    57
    Quote Originally Posted by Just Jeff View Post
    I doubt sil gives much more wind protection than breathable DWR. DWR is pretty hard to blow through even in a concentrated area, so I bet not much wind gets through. Windsuits are made from DWR.

    Having an extra layer of material with an air gap between that layer and your insulation will make you much warmer, too. Like a hammock sock.
    I agree. I had just recalled my layering of clothes and thought....noone really uses silnylon as an outer shell.....
    Scott

    "Man is a stream whose source is hidden."
    RWE

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •