Originally Posted by
nanok
regarding the tarp sagging when loading a "flat hang angle" hammock: this will typically happen if the tarp is attached on the hammock suspension, not at the tree (if you attach to the tree straps, or very close to the tree, this won't be much of a problem), and it will happen with line which has no stretch: when you get in the hammock and load the system, the hang angle will significantly increase (because of the physics i was describing above: the angle is shallow, so the loads in the suspension and hammock are multiplied, thus there's more stretch, which will change the hang angle, until an equilibrium is reached); if the tarp ridgeline is attached, for instance, somewhere in the middle of the suspension (between tree and hammock), then with the stretch and change in angle that ensues, the two attachment points will endup closer together, even if not by much, and because dyneema stretches basically none under the loads which a tarp puts on it (because we use hugely oversized dyneema line for tarp ridgelines, otherwise it would be unconfortable to handle -- i have some 1mm dyneema which is rated for 200kgf break strength, that's still too strong, and 1mm is torture already to deal with by hand, especially in the cold), then even a few millimeters of movement will change the tension in the ridgeline to basically zero, resulting in a saggy tarp; the solution is to attach at the tree, or use a ridgeline made of something which will allow you to store some ellastic deformation (like nylon, which everybody seems to recommend against for tarp ridgelines ...because it's stretchy), this way, when the tarp moves, because of wind or suspension movements or what not, the ridgeline will not immediately lose all tension after a few mm of offset, but instead it will "adapt" and stay in varying degrees of tautness, hence avoiding spectacularly flapping tarp shows.
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