Hey guys, i have been searching round the forum and cant quite find the actual numbers involved in dutch clips. I just finished making my own dutch clips out of 3/8 aluminum, and want to know how much actual force is put on the for a person of and average male weight: say, 200lbs. Does anyone know??? can someone shed any light on this??
Thanks,
Dan
You might enjoy this thread over at Whiteblaze considering the lateral forces a hammock places on the lateral supports whether they be a wall in a house, a tree, or a dutch clip or biner
http://www.whiteblaze.net/forum/show...highlight=math
At a 30 degree sag angle, the load on EACH suspension line us equal to the weight in the hammock. 200# in the hammock means 200# tension on each line.
It would seem to be half of the weight but trigonometry says otherwise. There are several threads on hammock loading on suspension lines at different angles.
Hmm... that's tricky. Because of the angles of the strap going around the tree the forces on the clip really are a combination of bending and tension. The bigger the tree, the less the bending plays a role... but by then you'd probably have a lot of force being taken up by friction anyway...
So assuming you had an infinitely large diameter tree with frictionless bark, the tension pulling the clip apart would be 100#. Did that help? Didn't think so.
That is wrong. to have friction, you must have displacement or movement.Originally Posted by matto
So assuming you had an infinitely large diameter tree with frictionless bark, the tension pulling the clip apart would be 100#. Did that help? Didn't think so.
No, there's usually quite a bit of static friction on a tree strap.
I'm 250lbs at 20deg angle I put about 140lbs side load on the strap. so at my weight the clip should hold 240lbs with a safety factor of 2 the clip it should hold 440lbs without break.
So I was slightly off earlier. I sat down and worked out the forces involved. Worst case is the clip will have to sustain a static load of 3x the line tension load (assuming you're using a dutch clip in the typical way everyone rigs it). So for a 200 lb line tension, the clip could see a static load of 600 lbs. Bear in mind that is just a static load - the dynamic loads can be way higher.
I think RainMan's rule of thumb of having every load bearing element in a suspension system rated to 2000 lbs is a very good one.
Just my two cents.
I don't think the force is 3x the tension in the strap. i'd like to see your free body diagram because i don't think it's correct. It's a lateral force or a K vector that is placed on the strap.
Yep. I went back over it and I was wrong (thats what I get for trying to do math at 4 am). I haven't looked at the math thread, but I think its time I quiet down and admit defeat before I get my foot deeper in my mouth :-P
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