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.
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.
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.