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3/32" Hammock Hanging Rope?

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  • ra1@imrisk.com
    3/32 Hammock Hanging Rope? I ordered some T-100 3/32 line from West Marine yesterday as a trial to decrease weight and bulk of my hammock straps. From the
    Message 1 of 22 , Aug 4, 2004
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      3/32" Hammock Hanging Rope?

      I ordered some T-100 3/32 line from West Marine yesterday as a trial to decrease
      weight and bulk of my hammock straps.

      From the beginning, I have always used Ed's method of hammock straps and find
      significant advantages to 1 inch webbing. However, I find it harder and harder
      to justify the 30 feet of webbing I have been carrying. It takes up a full
      third of the bulk of my hammock. The weight is not inconsiderable.

      Yesterday, I was out on the West marine catalog page to find the orange 1/16
      inch Pulse Line which works so very well for tarp pull outs. I happened upon
      T-100 cord which is a low stretch spectra core cord. The 3/32 line has a listed
      breaking strength of 950 pounds! That is stronger than the 1 inch webbing I now
      use.

      So I ordered 30 feet of it at $0.24 a foot. I think I will attach 6-10 feet to
      each end of a hammock and then use 1 inch webbing as a Hennessy Hammock style
      tree hugger. (I would not use thin cord on a tree without protection.) For
      now, I will be using a short piece of webbing on the hammock to which I tie the
      cord. Perhaps I will be able to avoid that connector and tie directly to the
      hammock in the future, but am a little afraid of the effect of thin cord on the
      hammock material.

      I also have a new (for me) and more elegent idea for attaching bug nets at the
      ends of the hammock.

      Results to be posted after some experiments.

      Risk
    • moneymakerjk1
      Risk.... what is your new elegant method....for the bug net? I also agree with the webbing weight and will be waiting to see how your new line works... If
      Message 2 of 22 , Aug 4, 2004
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        Risk....
        what is your new "elegant" method....for the bug net?
        I also agree with the webbing weight and will be waiting to see how
        your new line works...
        If it's breaking strength is 950 pounds, isn't it's safe working load
        strength about 10percent of that, say 95 pounds?

        or is 950 the safe working load?

        Jon
      • ra1@imrisk.com
        ... Jon, Patience Grasshoppa regarding the new method. It is not great revalation, but might be a little easier. As to the other question, it is always hard
        Message 3 of 22 , Aug 4, 2004
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          Quoting moneymakerjk1 <moneymakerjk1@...>:

          > Risk....
          > what is your new "elegant" method....for the bug net?
          > I also agree with the webbing weight and will be waiting to see how
          > your new line works...
          > If it's breaking strength is 950 pounds, isn't it's safe working load
          > strength about 10percent of that, say 95 pounds?
          >
          > or is 950 the safe working load?
          >
          > Jon
          >
          Jon,

          Patience Grasshoppa regarding the new method. It is not great revalation, but
          might be a little easier.

          As to the other question, it is always hard to tell if a breaking strength of
          950 pounds is the breaking strength or only a fraction of the breaking strength.
          However, if it holds without stretch, that will be enough. I think that
          hammocks pull with about 300 pounds of pull on each end the way I hang them.

          They certainly would not want me using it for a hammock if I asked.

          Rick
        • Mirage
          ... straps and find ... harder and harder ... up a full ... [snip...] ... 6-10 feet to ... Hammock style ... protection.) This is what I have evolved to. I
          Message 4 of 22 , Aug 4, 2004
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            --- In hammockcamping@yahoogroups.com, ra1@i... wrote:
            > From the beginning, I have always used Ed's method of hammock
            straps and find
            > significant advantages to 1 inch webbing. However, I find it
            harder and harder
            > to justify the 30 feet of webbing I have been carrying. It takes
            up a full
            > third of the bulk of my hammock. The weight is not inconsiderable.
            >
            [snip...]
            > So I ordered 30 feet of it at $0.24 a foot. I think I will attach
            6-10 feet to
            > each end of a hammock and then use 1 inch webbing as a Hennessy
            Hammock style
            > tree hugger. (I would not use thin cord on a tree without
            protection.)

            This is what I have evolved to. I found the bulk and weight of the
            30 ft of webbing rather too much for my tastes. I used what I had
            to make two 10' "tree huggers" (rather long, but some trees here in
            the PNW really require it).

            I then whipped the hammock hanging lines on the end of the hammock,
            leaving about 10' of line to hang from on either end.

            > I also have a new (for me) and more elegent idea for attaching bug
            nets at the
            > ends of the hammock.

            As always, I am anxious to see and hear what new ideas are brewing
            in our ever intrepid experimentor extraordinaire.

            Shane "Mirage"...
          • Ray Garlington
            ... This is what I have evolved to. I found the bulk and weight of the 30 ft of webbing rather too much for my tastes. I used what I had to make two 10 tree
            Message 5 of 22 , Aug 4, 2004
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              --- In hammockcamping@yahoogroups.com, "Mirage" <mirage@p...> wrote:
              This is what I have evolved to. I found the bulk and weight of the
              30 ft of webbing rather too much for my tastes. I used what I had
              to make two 10' "tree huggers" (rather long, but some trees here in
              the PNW really require it).

              One thing about ropes & trees. I've noticed that most of the
              rubbing/friction is in the first 1/4 turn of the rope around the
              tree. By the time you get to ropes about 5/16" diameter there is no
              significant damage (but some slight cosmetic scraping). I made some
              pads to protect this 1/4 turn, and a similar idea might work on the
              thinner cords. You might try some thick wall tubing for that area
              to act as a pad.

              Concerning breaking strength: I found the following rule of thumb
              for nylon rope on the Internet. (I have observed that woven
              polyester rope seems to have slightly higher breaking strength than
              predicted by this formula.)

              breaking strength = <circumference of line in inches> x 2,400

              so
              1/8" cord - .3927" in circumference = 942 pounds breaking strength
              3/16" cord - .589" C = 1413
              1/4" rope - .75" C = 1809 pounds breaking strength
              5/16" rope - .98" C = 2356
              3/8" rope - 1.18" C = 2827 pounds breaking strength
            • moneymakerjk1
              What about short sections of tubular nylon sling as a cover for the line as it goes around the tree? A one or two foot length wont weigh that much I suspect. I
              Message 6 of 22 , Aug 4, 2004
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                What about short sections of tubular nylon sling as a cover for the
                line as it goes around the tree? A one or two foot length wont weigh
                that much I suspect. I used to be a Ropes Course instructor, and the
                stuff is pretty hardy.

                jon
              • Ralph Oborn
                To engineer the straps/ropes how big of a safety factor do you plan on? If I weigh 200 lbs. and hang at 40°. then my static load on each rope is 155 lbs. is a
                Message 7 of 22 , Aug 4, 2004
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                  To engineer the straps/ropes how big of a safety factor do you plan
                  on?
                  If I weigh 200 lbs. and hang at 40°. then my static load on each
                  rope is 155 lbs. is a rope with 5oo lbs. breaking strength enough?
                  1000 lbs? 1500 lbs?




                  --- In hammockcamping@yahoogroups.com, "Ray Garlington"
                  <rgarling@y...> wrote:
                  > --- In hammockcamping@yahoogroups.com, "Mirage" <mirage@p...>
                  wrote:
                  > This is what I have evolved to. I found the bulk and weight of the
                  > 30 ft of webbing rather too much for my tastes. I used what I had
                  > to make two 10' "tree huggers" (rather long, but some trees here in
                  > the PNW really require it).
                  >
                  > One thing about ropes & trees. I've noticed that most of the
                  > rubbing/friction is in the first 1/4 turn of the rope around the
                  > tree. By the time you get to ropes about 5/16" diameter there is
                  no
                  > significant damage (but some slight cosmetic scraping). I made
                  some
                  > pads to protect this 1/4 turn, and a similar idea might work on
                  the
                  > thinner cords. You might try some thick wall tubing for that
                  area
                  > to act as a pad.
                  >
                  > Concerning breaking strength: I found the following rule of thumb
                  > for nylon rope on the Internet. (I have observed that woven
                  > polyester rope seems to have slightly higher breaking strength
                  than
                  > predicted by this formula.)
                  >
                  > breaking strength = <circumference of line in inches> x 2,400
                  >
                  > so
                  > 1/8" cord - .3927" in circumference = 942 pounds breaking strength
                  > 3/16" cord - .589" C = 1413
                  > 1/4" rope - .75" C = 1809 pounds breaking strength
                  > 5/16" rope - .98" C = 2356
                  > 3/8" rope - 1.18" C = 2827 pounds breaking strength
                • Rick
                  ... Hey Mirage, I was asleep at the wheel last month when y all were talking about knots for the hammock to rope junction. What is this whipping to 10 foot of
                  Message 8 of 22 , Aug 4, 2004
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                    Mirage wrote:

                    >
                    >I then whipped the hammock hanging lines on the end of the hammock,
                    >leaving about 10' of line to hang from on either end.
                    >
                    >
                    >
                    Hey Mirage,

                    I was asleep at the wheel last month when y'all were talking about knots
                    for the hammock to rope junction. What is this whipping to 10 foot of
                    line knot that you use?

                    Rick
                  • Rick
                    ... Hi Jon, I would want the weight to be suspended from the webbing against the tree for two reasons: - eliminate roll down - spread weight across the full
                    Message 9 of 22 , Aug 4, 2004
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                      moneymakerjk1 wrote:

                      >What about short sections of tubular nylon sling as a cover for the
                      >line as it goes around the tree? A one or two foot length wont weigh
                      >that much I suspect. I used to be a Ropes Course instructor, and the
                      >stuff is pretty hardy.
                      >
                      >jon
                      >
                      >
                      >
                      Hi Jon,

                      I would want the weight to be suspended from the webbing against the
                      tree for two reasons:
                      - eliminate roll down
                      - spread weight across the full width of the webbing

                      I have used the Hennessy Hammock style tree huggers and think they are a
                      good solution. They are also easy to make at home. What this is, is a 2
                      or three foot piece of webbing with the ends folded over and sewn into a
                      loop. To tie the hammock up to the tree, the hugger is either wrapped
                      around the back of the tree (big tree) or wrapped a couple times around
                      a smaller tree, ending up with the two loops equidistant from the
                      hammock. Then the rope is passed through the loops and tied with a
                      hennessy hammock knot.

                      I would not think that passing the rope through a piece of tubular
                      webbing would do much to protect the tree from anything except abrasion
                      (which is not the damage I am concerned about) or to reduce roll down.
                      BTW, the damage I am concerned about is pressure damage to the live
                      cambrium layer under the bark.

                      Risk
                    • Rick
                      ... Thus far I have done well with straps with a breaking strength of 300-600 pounds. I figure that with a breaking strength of 950 pounds, the 3/32 T-100
                      Message 10 of 22 , Aug 4, 2004
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                        Ralph Oborn wrote:

                        >To engineer the straps/ropes how big of a safety factor do you plan
                        >on?
                        >If I weigh 200 lbs. and hang at 40°. then my static load on each
                        >rope is 155 lbs. is a rope with 5oo lbs. breaking strength enough?
                        >1000 lbs? 1500 lbs?
                        >
                        >
                        >
                        Thus far I have done well with straps with a breaking strength of
                        300-600 pounds. I "figure" that with a breaking strength of 950 pounds,
                        the 3/32 T-100 cord is probably strong enough. All I know about stretch
                        is that the line is said to stretch less than one percent at 95 pounds
                        of tension.

                        Another cord I might think about would be the 1/8 inch Pulse Line which
                        is also about 900 pounds of strength.

                        This is just an experiment for me. I will not guess any conclusion
                        until I actually try it. I know that I will be *very* surprised if 3/32
                        inch cord is sufficient. But if it is, this offers considerable space
                        and weight savings, as well as a little cost savings.

                        Risk
                      • Mirage
                        ... hammock, ... knots ... foot of ... Initially, I was using 1/8 polypro line to whip the folded ends (instead of knots) together, then using a larks head
                        Message 11 of 22 , Aug 4, 2004
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                          --- In hammockcamping@yahoogroups.com, Rick <ra1@i...> wrote:
                          > Mirage wrote:
                          >
                          > >
                          > >I then whipped the hammock hanging lines on the end of the
                          hammock,
                          > >leaving about 10' of line to hang from on either end.
                          > >
                          > >
                          > >
                          > Hey Mirage,
                          >
                          > I was asleep at the wheel last month when y'all were talking about
                          knots
                          > for the hammock to rope junction. What is this whipping to 10
                          foot of
                          > line knot that you use?
                          >

                          Initially, I was using 1/8" polypro line to whip the folded ends
                          (instead of knots) together, then using a larks head from the straps
                          or rope to hang the hammock.

                          I just took it one step further, once I decided to go back to rope
                          and tree huggers. Instead of whipping with 1/8" line first, I just
                          use my 3/8 hang line and whipped it to the end, leaving the long end
                          comming out the end of the folds.

                          I'll post pics as soon I I get them back from my dads camera (I
                          borrowed my sons, and forgot it only has 16Mb and the pics turned
                          out poor as well).

                          Shane "Mirage"...
                        • Ray Garlington
                          ... plan ... As a practical example: Hennessey uses line with a breaking strength from about 1600 to 1800 pounds depending on the model. If the webbing used
                          Message 12 of 22 , Aug 5, 2004
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                            --- In hammockcamping@yahoogroups.com, "Ralph Oborn"
                            <polecatpop@y...> wrote:
                            > To engineer the straps/ropes how big of a safety factor do you
                            plan
                            > on?

                            As a practical example: Hennessey uses line with a breaking
                            strength from about 1600 to 1800 pounds depending on the model. If
                            the webbing used by the Speerians really is 800 pound breaking
                            strength, and they are not reporting problems then you can see that
                            Tom has built in a large safety factor.

                            It will be interesting to see if Rick ends up risking the 3/32"
                            which is typically used for working loads around 100 pounds. On a
                            positive note, it seems like it should work if the webbing he's been
                            using really only goes to 800 pounds.
                          • Ray Garlington
                            ... live ... Apx what pressure (in psi) will cause damage? We could calculate (or measure) the localized pressure being generated at the outside bark surface
                            Message 13 of 22 , Aug 5, 2004
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                              --- In hammockcamping@yahoogroups.com, Rick <ra1@i...> wrote:
                              > BTW, the damage I am concerned about is pressure damage to the
                              live
                              > cambrium layer under the bark.


                              Apx what pressure (in psi) will cause damage? We could calculate
                              (or measure) the localized pressure being generated at the outside
                              bark surface and stay above that figure. The exterior bark would
                              also act as padding serving primarily as a safety factor.

                              My experience with trees has been that they can survive quite well
                              even if cut through to the wood so long as decay does not start at
                              the injury site. You have to ring a tree most of the way around
                              (cut through the bark) to kill it.
                            • Dave Womble
                              ... Ray, you overlooked something in your comparison. The Hennessy, with its intergal ridgeline, generally puts more tension on the hammock support
                              Message 14 of 22 , Aug 5, 2004
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                                --- In hammockcamping@yahoogroups.com, "Ray Garlington"
                                <rgarling@y...> wrote:
                                > --- In hammockcamping@yahoogroups.com, "Ralph Oborn"
                                > <polecatpop@y...> wrote:
                                > > To engineer the straps/ropes how big of a safety factor do you
                                > plan
                                > > on?
                                >
                                > As a practical example: Hennessey uses line with a breaking
                                > strength from about 1600 to 1800 pounds depending on the model. If
                                > the webbing used by the Speerians really is 800 pound breaking
                                > strength, and they are not reporting problems then you can see that
                                > Tom has built in a large safety factor.
                                >

                                Ray, you overlooked something in your comparison. The Hennessy, with
                                its intergal ridgeline, generally puts more tension on the hammock
                                support ropes/straps because it typically is hung so that the hammock
                                support ropes/straps are more horizontally than a Speer hammock.
                                Sometimes, this difference in tension is quite severe and it is not
                                obvious that Hennessy is using a greater safety margin. This extra
                                tension would also carry over to the other discussion concerning tree
                                damage. (While the internal ridgeline does help in getting a
                                consistant 'hang', it is not without its drawbacks.)

                                Youngblood
                              • navjohn@aol.com
                                ... Yes, but our goal should be leave no trace -- and this means no visible damage to trees. Many public (and some private) campgrounds already have
                                Message 15 of 22 , Aug 5, 2004
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                                  In a message dated 8/5/04 10:35:38 AM, rgarling@... writes:


                                  My experience with trees has been that they can survive quite well
                                  even if cut through to the wood so long as decay does not start at
                                  the injury site.   You have to ring a tree most of the way around
                                  (cut through the bark) to kill it.


                                  Yes, but our goal should be leave no trace -- and this means no visible damage to trees.  Many public (and some private) campgrounds already have restrictions against tying anything to trees because of damage caused by careless campers.   Any scarring or bark loss, even if it causes no long-term damage to the tree, should be considered unacceptable to an ethical hammocker.
                                  John Wilson
                                • ra1@imrisk.com
                                  ... John, I agree that my concern is at a higher level than killing the tree - and I know Ray s is as well. I am concerned about scars from damage to any
                                  Message 16 of 22 , Aug 5, 2004
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                                    Quoting navjohn@...:

                                    >
                                    > In a message dated 8/5/04 10:35:38 AM, rgarling@... writes:
                                    >
                                    >
                                    > > My experience with trees has been that they can survive quite well
                                    > > even if cut through to the wood so long as decay does not start at
                                    > > the injury site. You have to ring a tree most of the way around
                                    > > (cut through the bark) to kill it.
                                    > >
                                    >
                                    > Yes, but our goal should be leave no trace -- and this means no visible
                                    > damage to trees. Many public (and some private) campgrounds already have
                                    > restrictions against tying anything to trees because of damage caused by
                                    > careless
                                    > campers. Any scarring or bark loss, even if it causes no long-term damage
                                    > to
                                    > the tree, should be considered unacceptable to an ethical hammocker.
                                    > John Wilson

                                    John,

                                    I agree that my concern is at a higher level than killing the tree - and I know
                                    Ray's is as well. I am concerned about scars from damage to any portion of the
                                    tree's live portion - under the bark.

                                    I am a little less worried about a little surface scrape of the outer bark,
                                    which is only some friction against the dead outer layer of the bark. But this
                                    is because I usually am using a tree that will seldom/never have another hammock
                                    hung from it.

                                    I guess it is not truely leave no trace, in the same way that stepping on grass
                                    is not actually leave no trace.
                                    >

                                    Rick
                                  • zippydooda
                                    Hey Risk, as far as stretch, the amount of stretch per unit of load should be higher for the first unit of load than for subsequent units. Sorry, which means
                                    Message 17 of 22 , Aug 5, 2004
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                                      Hey Risk, as far as stretch, the amount of stretch per unit of load
                                      should be higher for the first unit of load than for subsequent
                                      units. Sorry, which means that if you get 1% stretch with the first
                                      95 lbs, that the next 95 pounds should be less than 1% stretch. So
                                      for 450 lbs, you are looking at maybe 4% stretch or less.

                                      Good luck with the experiment, and thanks for posting your ideas.
                                      Hopefully the knots you use won't reduce the ultimate tensile
                                      strength too much. Maybe put a big mattress under you when you do
                                      the testing ;-)

                                      Bill in Houston

                                      --- In hammockcamping@yahoogroups.com, Rick <ra1@i...> wrote:
                                      > Ralph Oborn wrote:
                                      >
                                      > >To engineer the straps/ropes how big of a safety factor do you
                                      plan
                                      > >on?
                                      > >If I weigh 200 lbs. and hang at 40°. then my static load on each
                                      > >rope is 155 lbs. is a rope with 5oo lbs. breaking strength enough?
                                      > >1000 lbs? 1500 lbs?
                                      > >
                                      > >
                                      > >
                                      > Thus far I have done well with straps with a breaking strength of
                                      > 300-600 pounds. I "figure" that with a breaking strength of 950
                                      pounds,
                                      > the 3/32 T-100 cord is probably strong enough. All I know about
                                      stretch
                                      > is that the line is said to stretch less than one percent at 95
                                      pounds
                                      > of tension.
                                      >
                                      > Another cord I might think about would be the 1/8 inch Pulse Line
                                      which
                                      > is also about 900 pounds of strength.
                                      >
                                      > This is just an experiment for me. I will not guess any conclusion
                                      > until I actually try it. I know that I will be *very* surprised if
                                      3/32
                                      > inch cord is sufficient. But if it is, this offers considerable
                                      space
                                      > and weight savings, as well as a little cost savings.
                                      >
                                      > Risk
                                    • Thomas Peltier@Goldenautomotive.com
                                      Hey Risk, as far as stretch, the amount of stretch per unit of load should be higher for the first unit of load than for subsequent units. Sorry, which means
                                      Message 18 of 22 , Aug 5, 2004
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                                        Hey Risk, as far as stretch, the amount of stretch per unit of load
                                        should be higher for the first unit of load than for subsequent
                                        units. Sorry, which means that if you get 1% stretch with the first
                                        95 lbs, that the next 95 pounds should be less than 1% stretch. So
                                        for 450 lbs, you are looking at maybe 4% stretch or less.

                                        Good luck with the experiment, and thanks for posting your ideas.
                                        Hopefully the knots you use won't reduce the ultimate tensile
                                        strength too much. Maybe put a big mattress under you when you do
                                        the testing ;-)

                                        Bill in Houston


                                        Now I know that my climbing rope stretches much farther relatively on a
                                        long fall than a short one.

                                        Oh and I use a bouldering crash pad when I'm experimenting. Fortunately
                                        I have yet to need it.

                                        Tom

                                        P.s. Now were is that piece of wood... Ah yes,, knock knock
                                      • zippydooda
                                        Yeah, I was afraid I wasn t making sense. The rope will stretch more as the load increases, you are right. It s just that in the first 95 pounds (or
                                        Message 19 of 22 , Aug 5, 2004
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                                          Yeah, I was afraid I wasn't making sense. The rope will stretch more
                                          as the load increases, you are right. It's just that in the first 95
                                          pounds (or whatever) the rope will stretch more, as the individual
                                          fibers and strands shift against each other and lay down flat against
                                          each other. One the rope is taut and all the strands are compacted
                                          against each other, it will be relatively more difficult to stretch.

                                          Bill in Houston

                                          --- In hammockcamping@yahoogroups.com, "Thomas Peltier@G..."
                                          <Thomas@G...> wrote:
                                          > Hey Risk, as far as stretch, the amount of stretch per unit of load
                                          > should be higher for the first unit of load than for subsequent
                                          > units. Sorry, which means that if you get 1% stretch with the first
                                          > 95 lbs, that the next 95 pounds should be less than 1% stretch. So
                                          > for 450 lbs, you are looking at maybe 4% stretch or less.
                                          >
                                          > Good luck with the experiment, and thanks for posting your ideas.
                                          > Hopefully the knots you use won't reduce the ultimate tensile
                                          > strength too much. Maybe put a big mattress under you when you do
                                          > the testing ;-)
                                          >
                                          > Bill in Houston
                                          >
                                          >
                                          > Now I know that my climbing rope stretches much farther relatively
                                          on a
                                          > long fall than a short one.
                                          >
                                          > Oh and I use a bouldering crash pad when I'm experimenting.
                                          Fortunately
                                          > I have yet to need it.
                                          >
                                          > Tom
                                          >
                                          > P.s. Now were is that piece of wood... Ah yes,, knock knock
                                        • Thomas Peltier@Goldenautomotive.com
                                          as the individual fibers and strands shift against each other and lay down flat against each other. _________________________ Which would explain why short
                                          Message 20 of 22 , Aug 6, 2004
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                                            as the individual
                                            fibers and strands shift against each other and lay down flat against
                                            each other.
                                            _________________________

                                            Which would explain why short falls tend to be harder on ropes than long
                                            falls.

                                            Tom
                                          • rambler4466
                                            ... BTW Recently purchased 30 of 1 polypro. heavy link webbing. It weighs 5.5oz.
                                            Message 21 of 22 , Aug 7, 2004
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                                              --- In hammockcamping@yahoogroups.com, "Thomas Peltier@G..."

                                              BTW Recently purchased 30' of 1" polypro. "heavy link" webbing. It
                                              weighs 5.5oz.
                                              >
                                            • Dave Womble
                                              ... If ... that ... with ... hammock ... tree ... Since this comes up from time to time, I decided to upload a MSExcel spreadsheet of mine that shows the
                                              Message 22 of 22 , Aug 20, 2004
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                                                --- In hammockcamping@yahoogroups.com, "Dave Womble" <dpwomble@y...>
                                                wrote:
                                                > --- In hammockcamping@yahoogroups.com, "Ray Garlington"
                                                > <rgarling@y...> wrote:
                                                > > --- In hammockcamping@yahoogroups.com, "Ralph Oborn"
                                                > > <polecatpop@y...> wrote:
                                                > > > To engineer the straps/ropes how big of a safety factor do you
                                                > > plan
                                                > > > on?
                                                > >
                                                > > As a practical example: Hennessey uses line with a breaking
                                                > > strength from about 1600 to 1800 pounds depending on the model.
                                                If
                                                > > the webbing used by the Speerians really is 800 pound breaking
                                                > > strength, and they are not reporting problems then you can see
                                                that
                                                > > Tom has built in a large safety factor.
                                                > >
                                                >
                                                > Ray, you overlooked something in your comparison. The Hennessy,
                                                with
                                                > its intergal ridgeline, generally puts more tension on the hammock
                                                > support ropes/straps because it typically is hung so that the
                                                hammock
                                                > support ropes/straps are more horizontally than a Speer hammock.
                                                > Sometimes, this difference in tension is quite severe and it is not
                                                > obvious that Hennessy is using a greater safety margin. This extra
                                                > tension would also carry over to the other discussion concerning
                                                tree
                                                > damage. (While the internal ridgeline does help in getting a
                                                > consistant 'hang', it is not without its drawbacks.)
                                                >
                                                > Youngblood

                                                Since this comes up from time to time, I decided to upload a MSExcel
                                                spreadsheet of mine that shows the results of the analysis I did of
                                                the forces associated with using an integral ridgeline. I hope it
                                                will clear up the point I was trying to make. Basically without an
                                                integral (or tensioned) ridgeline the forces are just Force 1... I
                                                try to hang my homemade versions of the Speer Hammock such that Angle
                                                1 is at 30 degrees or so. With the Hennessy Hammocks, Angle 1 is
                                                typically less (my guess is somewhere around 15 to 30 degrees?)...
                                                depending on how taut you tie the hammock. This means that Force 1
                                                might be higher when using hammocks with an intergral ridgeline and
                                                that the tension on that ridgeline can sometimes exceed the tension
                                                on the hammock ropes (ie, Force 3 exceeds Force 1 on my
                                                spreadsheet). My thinking is that the ridgeline cord may be the
                                                first thing to fail if a hammock with an intergral ridgeline is
                                                overstressed due to hanging it too taut, and I say this because my
                                                observation with the HH that I had was that the ridgeline cord was
                                                not as thick (and therefore not as strong) as the hammock ropes while
                                                my analysis (which hasn't been scrutinized) suggests that maybe it
                                                should be. The spreadsheet is in the Files section under my folder.

                                                Youngblood
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