Results 1 to 6 of 6
  1. #1
    Member rocketBoy's Avatar
    Join Date
    Dec 2012
    Location
    Huntsville, AL
    Hammock
    WBBB
    Suspension
    Woopie Slings
    Posts
    77

    Ridge Line Length

    I've heard the suggestion that a structural ridge line should be about 83% of the hammock length. Where does that 83% come from? When discussing hammock lengths are we usually discussing the length of the fabric before the end whippings/suspension attachment or the length between the whippings. I would assume it was the distance between end whippings but my WBBB is supposedly a 10' hammock but measures noticeably less than that between the suspension attachments. Thanks

  2. #2
    Senior Member
    Join Date
    Jan 2011
    Location
    IN
    Hammock
    WBRR, Lots of DIY
    Tarp
    MacCat; Cloudburst
    Insulation
    Lynx, HG T/UQ, AHE
    Suspension
    Varies
    Posts
    8,464
    Quote Originally Posted by rocketBoy View Post
    I've heard the suggestion that a structural ridge line should be about 83% of the hammock length. Where does that 83% come from?

    Probably just what it works out to be when a 30* hang angle is used.

    When discussing hammock lengths are we usually discussing the length of the fabric before the end whippings/suspension attachment or the length between the whippings. I would assume it was the distance between end whippings but my WBBB is supposedly a 10' hammock but measures noticeably less than that between the suspension attachments...

    Everyone seems to use different points to measure from. Many manufacturers quote the length of the fabric blank before sewing the end channels. Some measure the blank after sewing. In short...measure from the points you will attach the SRL and use that length to calculate the 83%.
    .........................

  3. #3
    Senior Member
    Join Date
    Jul 2013
    Location
    Nashville, Tennessee
    Hammock
    Dream Hammock Thunderbird
    Tarp
    Warbonnet Superfly
    Insulation
    kAQ New River, DIY
    Suspension
    Varies w/hammock
    Posts
    312
    If you use a UCR to do your ridge line you can have some adjustability so you don't have to get a fixed length of line "right". you can make the UCR and then fiddle with it. That's what I did

  4. #4
    Member rocketBoy's Avatar
    Join Date
    Dec 2012
    Location
    Huntsville, AL
    Hammock
    WBBB
    Suspension
    Woopie Slings
    Posts
    77
    It's no problem to to an adjustable ridge line and just tweak it until it's right. I was mostly just curious where the 83% came from. I was thinking it was from the 30 deg hang angle but it doesn't seem to be. Assuming a point load at the center of the hammock, ridge line length divided by hammock body length should be equal to cos(30deg), but cos(30deg) is 87%, not 83%. Anybody know where that 83% actually comes from?

  5. #5
    New Member
    Join Date
    Sep 2012
    Location
    Buford, GA
    Hammock
    Simply Light Tree Runner DL
    Tarp
    Guide Gear 8 x 8
    Insulation
    REI Airrail 1.5
    Suspension
    Whoopies & a Spike
    Posts
    20
    The round-about suggested starting point for a ridgeline is 5/6 the length of your hammock.

    5/6 = .833333 (or 83 1/3%).

    I believe that's where the 83% number comes from.

  6. #6
    New Member wizzard's Avatar
    Join Date
    Sep 2013
    Location
    St. John's NL
    Hammock
    Hennessey Explorer Asym Zip
    Tarp
    Warbonnet superfly
    Insulation
    Hennessey system
    Suspension
    DIY whoopies
    Posts
    5

    Where 83% comes from...

    Saying that the 83% comes from 5/6 is not really explaining why 83% because you could just as well ask, why 5/6??

    My guess is that 30 degrees is the recommended angle for a hammock to hang from horizontal to be comfortable. Given this, you can think of the hammock as a triangle that has a long side on top with 30 degree angles going down to a point where there is a 120 degree angle at the bottom of the hang. With this shape of a triangle, the rules of geometry say that if two short sides are 50 inches long, the long top side must be 86 inches long. In other words, if your hammock hung the way that a triangle does and was 100 inches long (50 + 50) the ridgeline would be 86 inches, or 86% of your hammock length.

    My bet is that the 83% comes from someone whose math skills are better than mine and has based the calculation on the hammock not looking like a triangle, but following a parabolic curve...which would shorten the ridgeline to...83%.

    In other words, a ridgeline that is 83% of the straightline length of a hammock will cause it to hang 30 degrees from horizontal....

    All of this begs the question of.....why is 30 degrees more comfortable than 35...or 25 ? I think we should all be experimenting!

  • + New Posts
  • Similar Threads

    1. Ridge line length
      By litetrek in forum General Hammock Talk
      Replies: 16
      Last Post: 06-14-2013, 09:46
    2. Full length ridge line vs. tying out from ridge line tie outs
      By Buenos in forum OES Tarps (no longer in business)
      Replies: 36
      Last Post: 03-20-2013, 19:41
    3. Ridge line length 83%?
      By jaitch in forum Suspension Systems, Ridgelines, & Bug Nets
      Replies: 4
      Last Post: 10-29-2012, 09:47
    4. Ridge line length
      By fisherman in forum General Hammock Talk
      Replies: 2
      Last Post: 01-20-2011, 23:45
    5. Ridge line length?
      By pgibson in forum Suspension Systems, Ridgelines, & Bug Nets
      Replies: 10
      Last Post: 07-23-2009, 22:17

    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
    •