Loading ...
Sorry, an error occurred while loading the content.
 

RE: Hammock Camping Near Disaster!

Expand Messages
  • Ed Speer
    Wow, Flyfisher. Thanks for the info. I ve never seen velcro cause a tear in ripstop nylon, but I ll certainly watch for that in the future. Good luck with
    Message 1 of 8 , Mar 25, 2003
      Message
      Wow, Flyfisher.  Thanks for the info.  I've never seen velcro cause a tear in ripstop nylon, but I'll certainly watch for that in the future.  Good luck with your next hammock...Ed
      -----Original Message-----
      From: geoflyfisher [mailto:geoflyfisher@...]
      Sent: Monday, March 24, 2003 3:24 PM
      To: hammockcamping@yahoogroups.com
      Subject: Re: Hammock Camping Near Disaster!

      Regarding the cause/anatomy/etc...

      the rip is at the end of the loop velcro.  It is perpendicular to the
      edge of the fabric and extends about 6 inches into the hammock. 

      My guess is the cause was the hook velcro of my bug net.  I had sewn
      hook velcro all the way to the end of the bug net, somewhat
      differently than you suggest.  It is a little more form fitting to
      the opening of the hammock.  I'd guess that the hooked together
      velcro on the bug net somewhere outside the overhand knot of the
      hammock got stuck and as I sat down on the edge of the hammock the
      hook velcro, or the sharp edge on that velcro, acted as a knife,
      starting a rip.  

    • geoflyfisher
      ... you ... I did some work with the ripped hammock over the weekend. There is a new theory on what caused the tear. It looks like the tear actually started
      Message 2 of 8 , Mar 31, 2003
        --- In hammockcamping@yahoogroups.com, "Ed Speer" <info@s...> wrote:
        > Wow! Flyfisher--glad you were able to salvage your hike. Your quick
        > thinking saved the day (or the night).
        >
        > I'm most interested in what caused the ripped hammock, as I'm sure
        you
        > are.

        I did some work with the ripped hammock over the weekend. There is a
        new theory on what caused the tear.

        It looks like the tear actually started in a bartack at the end of
        the velcro. The bartack was perpendicular to the edge of the
        hammock. The tear, once started, pulled through the hem of the
        hammock material and then about 6 inches into the body of the hammock.

        The material was white ripstop. It was listed as 1.9 oz but
        examination now leads me to think it could well be 1.1 oz instead. I
        have not weighed it, but will do so.

        As you know, Ed, the edge of the hammock takes some extra tension
        entering and exiting. Along the edge of my hammock, I had sewn the
        velcro and it ended about 6 inches short of the knot. Because the
        velcro is relatively non elastic compared to the nylon body of the
        hammock, at the end of the velcro, there is a stress point. That was
        the reason I had put the bartack in to begin with... but it ended up
        being the weak point instead.

        Plans for next experiment are to continue the velcro all the way into
        the knot both for strength and better bug protection, and to attach
        the insulator/poncho with snaps instead of velcro.

        <><
      • Ed Speer
        Thanks for the update Flyfisher. I, too have had simialr trouble elsewhere w/ heavy bar tacks--It s easy to reach a point where the additional thread in the
        Message 3 of 8 , Apr 1, 2003
          Message
          Thanks for the update Flyfisher.  I, too have had simialr trouble elsewhere w/ heavy bar tacks--It's easy to reach a point where the additional thread in the bar tack is not needed for strength, but the extra needle holes weaken the fabric by perforating it too much.  Kind of a catch22.  Best of luck with the remake...Ed
           
           
          -----Original Message-----
          From: geoflyfisher [mailto:geoflyfisher@...]
          Sent: Monday, March 31, 2003 8:28 AM
          To: hammockcamping@yahoogroups.com
          Subject: Hammock Camping Near Disaster! "Autopsy" Results

          --- In hammockcamping@yahoogroups.com, "Ed Speer" <info@s...> wrote:
          > Wow! Flyfisher--glad you were able to salvage your hike.  Your quick
          > thinking saved the day (or the night). 

          > I'm most interested in what caused the ripped hammock, as I'm sure
          you
          > are. 

          I did some work with the ripped hammock over the weekend.  There is a
          new theory on what caused the tear.

          It looks like the tear actually started in a bartack at the end of
          the velcro.  The bartack was perpendicular to the edge of the
          hammock.  The tear, once started, pulled through the hem of the
          hammock material and then about 6 inches into the body of the hammock.

          The material was white ripstop.  It was listed as 1.9 oz but
          examination now leads me to think it could well be 1.1 oz instead.  I
          have not weighed it, but will do so.

          As you know, Ed, the edge of the hammock takes some extra tension
          entering and exiting.  Along the edge of my hammock, I had sewn the
          velcro and it ended about 6 inches short of the knot.  Because the
          velcro is relatively non elastic compared to the nylon body of the
          hammock, at the end of the velcro, there is a stress point.  That was
          the reason I had put the bartack in to begin with...  but it ended up
          being the weak point instead. 

          Plans for next experiment are to continue the velcro all the way into
          the knot both for strength and better bug protection, and to attach
          the insulator/poncho with snaps instead of velcro. 

          <>< 



          To unsubscribe from this group, send an email to:
          hammockcamping-unsubscribe@yahoogroups.com



          Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
        • rosaleen43@aol.com
          Hi, Everyone! There have been several posts trying to study a failure in a hammock, starting at the point of a bar tack. Just to add points to consider in
          Message 4 of 8 , Apr 2, 2003
            Hi, Everyone!

            There have been several posts trying to study a failure in a hammock, starting at the point of a bar tack.

            Just to add points to consider in sewing.  In my experience, there seem to be materials that perform as if I'd just made perforations indicating where I want to be able to tear something off.  Notably, stitching on pieces of foam/mylar for a reflector.

            There are likely a lot of reasons for this.  Let me throw in one thought for some of you who have less sewing experience.  Manufacturers have come out with different needle points, targeting them to knits or wovens.  There are also some sold as "universal point."

            So, along with length and diameter, dullness and burrs, we may also need to concern ourselves with the actual type of needle point.  Before starting a large project, or one that needs to bear weight, sew a test strip and subject it to the forces you anticipate for you finished project.  I haven't sewn enough silnylon to know, yet, it does best with the sharper needles meant for wovens or the ball points meant for knits.  It may just behave differently from what we expect. 

            Cheers, and happy tinkering!

            Rosaleen

          • geoflyfisher
            Hi Rosaleen, Great points in your post (pun intended ;) ) The hammock material which failed was uncoated ripstop nylon. I was using a standard sewing machine
            Message 5 of 8 , Apr 2, 2003
              Hi Rosaleen,

              Great points in your post (pun intended ;) )

              The hammock material which failed was uncoated ripstop nylon. I was
              using a standard sewing machine needle... not ball point, not
              cutting needle, just sharp... When I made the bar tack, I had just
              sewn dozens of feet of hook and also loop velcro, which tends to
              cause burrs on the needle occasionally.

              I believe that ripstop nylon would be less likely to be weakened by
              sewing than silnylon is. The silicone stablizes the fabric thread
              and may allow it to be cut by a needle when regular woven cloth
              threads would be allowed to be separated by the needle.

              For this reason, silnylon and tyvek may have some inherent weakness
              for the weight supporting part of hammock making which the woven
              ripstop does not.

              I pointed out what I did to allow others to avoid over sewing the
              velcro at such a vulnerable location. As Ed Speer noted, it is
              likely the many needle punctures of the material which caused
              weakness instead of strength.

              <><

              --- In hammockcamping@yahoogroups.com, rosaleen43@a... wrote:
              > Hi, Everyone!
              >
              > There have been several posts trying to study a failure in a
              hammock,
              > starting at the point of a bar tack.
              >
              > Just to add points to consider in sewing. In my experience, there
              seem to be
              > materials that perform as if I'd just made perforations indicating
              where I
              > want to be able to tear something off. Notably, stitching on
              pieces of
              > foam/mylar for a reflector.
              >
              > There are likely a lot of reasons for this. Let me throw in one
              thought for
              > some of you who have less sewing experience. Manufacturers have
              come out
              > with different needle points, targeting them to knits or wovens.
              There are
              > also some sold as "universal point."
              >
              > So, along with length and diameter, dullness and burrs, we may also
              need to
              > concern ourselves with the actual type of needle point. Before
              starting a
              > large project, or one that needs to bear weight, sew a test strip
              and subject
              > it to the forces you anticipate for you finished project. I
              haven't sewn
              > enough silnylon to know, yet, it does best with the sharper needles
              meant for
              > wovens or the ball points meant for knits. It may just behave
              differently
              > from what we expect.
              >
              > Cheers, and happy tinkering!
              >
              > Rosaleen
            Your message has been successfully submitted and would be delivered to recipients shortly.