Thread: Max weight/line stress View Single Post
03-12-2007, 23:08   #5
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Join Date: Oct 2006
Location: New Orleans, LA
Posts: 3,619
Quote:
 Originally Posted by Sandy B Not sure where to put this I just finished a rigging class(navy) and one of the subjects was sling angle stress and the weight effects of a load when the angles are changed. SO for all who always wanted to know what type/how much of load they are putting on there tree huggers and hammock line, here it is: ref: NAVFAC P-307 when a sling angle is reduced to 0 degree the stress is increased by a factor of 13 when the angle is at 5 degrees the stress is increased by a factor of 11.49 so if I tighten my hammock to zero degrees and then lay in it, the lines are about 5 degrees. Now take my weight of 200 lbs times the 11.49 and you have 2298lbs ON EACH side. So, why does the 1400lb line hold???? Answer, It has a built in safety factor, like 6 to 1 And the load(weight) I place on the hammock is slowly added. (don't jump into your hammock) And for all those who want to tie a knot in your line, This will reduce the line strenght by 50% (the HH Knot is really a bend/lashing and not a Knot) There is alot more info on this, If any one wants to 'really' know. Thanks Sandy B
I would say they hold because you are putting half your weight on each support, or 100lbs converted to 1144lbs of stress at 0 degrees. Well below the 1400 lbs breaking strength and any safty factor built in.

An interesting point on the knots. I have heard for a long time and in different places that knots reduce rope strength by 50%.

An interesting question would be which lashing can we use in place of the knots in our setups? Also how much do lashing effect the strength of the rope? I am thinking it is some, but how much.

Quote:
 Originally Posted by blackbishop351 Yeah mine's probably at about 5* before I get in it - and that's as tight as I can make it (my HH, anyway). Probably at least 20-25* when I'm in it, maybe more.

That's about where I am. No matter how taught I start, I usually end up around 20 degrees.

BTW, I don't usually gentily get in. I just sit in and swing around. You should see what I do to test it for the first hang.
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