Usually my world of physics is limited to how to over come inertia and get my behind out of the hammock in the morning. I prefer to leave the weighter matters of hammock geometry to the likes of Doc or Ironfish.
However, I have been thinking about the hammock configuration that I have been using for the past two weeks. I epoxied part of my floor and the toxic odor has necessitated moving outdoors for the past weeks while the epoxy cures and the toxic cloud dissipates. I used a similar system suspended from the truss joists in my garage in Bozeman with the mule tape hanging straight down to the ridge pole (I ran a bar or two by four between several truss chords to spread the weight out)
I was using a couple of trees in the yard, but when the weather turned to rain I decided to suspend a GE in the old shed on my place. It isn't much of a shed, but it sure is a lot nicer than the two trailers and the milled log stacked together that I've spent the last year and a half tearing a part and disposing of. The shed has survived for a while as a convenient place to stack tools and store extraneous stuff.
Here are a couple of pictures of what I set up:
HammockShedHang10292018_2.jpgHammockShedHang10292018_4.jpg
What got me to thinking about this was a recent post where a fellow was seeking some advice on constructing the stand, and secondly, seeing the stand Sierra Madre was using for their video conference about the Ninox. I suggested to the hammock stand builder that he incorporate a ridge pole and some one else commented after he had built the stand that he should add some blocking to the ridge line two by fours for strength. In addition, now that I think about it, I have been using the same type of set up with my "turtle dog" aluminum tripods since I have the ridge pole hanging from the tripod by nylon webbing loops instead of being secured to the tripod pole top junction.
However, the moral physics of the story is: If you suspend a ridge pole from either beams (in my case), rafters or second story floor joists, or even two vertically planted poles the stress is a whole lot less (approximately one half) than if you rig a hammock between two suspension points. If you look at the pictures the ridge pole is supported by a couple of mule tape loops with each bearing half the weight of the hammock and peacefully slumbering person. However the force from a typical suspension system put far more force on each end point. This extra force is what causes folks to bolt a solid top piece on their hammock stand, or beef up the two planted posts in anticipation of the inward forces causing potential failure.
But if a simple ridge pole is suspended from the top of planted posts the force is almost straight down the planted posts with very little concern for the force that wants to collapse the posts inward. Solid as a rock! Let say you lag a hank of chain to the top of the post, then loop the chain around the ridge pole, pick the height you want for the ridge pole and slip the corresponding link over the top lag bolt. Using cordage tied to the desired length will work too. In my set up I can take additional wraps around the ridge pole to shorten the mule tape and hence raise the hammock height.
The usual inward forces caused by supporting a person in a hammock are absorbed by the solid ridge pole.
I also got to thinking about the superiority of this setup for folks setting hammocks up indoors. Instead of lagging a bolt or attachment to a wall member (typically a weak two by four) what if you lagged into the rafters or second story floor joists. Then suspend a cord or mule tape straight down to a ridge pole. There would less force and the force would not be a twisting force caused by a normal suspension system hang.
I have been thinking about using this system in my home by suspending the ridge pole from the red iron trusses that are eight feet apart. I can use four pole sections for sixteen feet for GE hammocks and two sections for my Hammocktent hammocks. During the daytime I can easily move the hammock/ridge pole system over to the wall or hoist it up toward the ceiling and have it out of the way in my 30x40 metal building "tiny home". The same would be true for folks with posts set in the yard, you wouldn't need to have a top bar permanently fastened and potentially be in the way. Just take the ridge pole down and store when not in use. PS: Physics makes my head hurt.
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Originally Posted by Baka Dasai
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