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Make your own tensahedron stand

Bushcrafted on the spot, lashed connections. Published here previously, it’s just too beautiful not to re-use.

The idea behind our Tensa4 stand is so simple that inexpensive homemade versions are irresistible. There have been several dozen DIY builds shown online since we showed our prototype in October 2017. They can be hard to find in the ephemeral jumble of social media streams, with their poor search features, and build details are scarce. To help fix this, we present below three builds that seem to us especially good: simple, cheap, and not requiring fancy tools or skills to make.

Dane’s bare bones tensahedron

One of the earliest builds is still startling for low cost, at $21. Poster Daneaustin3 presented it in November 2017:

No stand ridgeline necessary when hammock has one.

In his own words:

3/4″ EMT conduit with 220lbs in it. I used steel cable to hold the conduit together.
Parts:
4x 3/4 conduit cut to 95″ (fits in my 8′ bed truck) $4.25 ea
4x 1′ steel cable $.36 per foot
4x cable clamps $.63 ea.
Total cost $21

Travis’s segmented fence top rail tensahedron

Hammocks not commonly seen in these here Utah parts.

Travis Hodgson (aka fivefreds), wasn’t the first to use fence top rail instead of EMT, but he did put up some good photos. Top rails are heavy and strong. These come typically 10′ long with one end swaged. Chop the pole in half for easier transport, and you can insert the swaged end into the middle to rejoin, securing with a pin. 10′ is more than long enough, so you might chop 3-10″ further off the sections.

Travis’s pole connectors are super elegant: continuous loops of Amsteel rope pushed through grommeted holes drilled in the pole ends, and then looped over the pole ends to secure.

It’s important to assure that the holes in the poles don’t cut the rope used to connect them. Grommets are a good idea, because steel can be hard to de-burr adequately. The coolest grommets I’ve seen are short pieces of copper tubing inserted through the holes and hand peened smooth:

Hard metal, meet soft metal. Artisanal peening.

Mike’s telescopic EMT conduit clothes line tensahedron

Save on power bills with this elegant laundry desiccation apparatus where permitted by homeowner covenant.

Mike Jones’ build uses two telescoping sizes of conduit to allow the poles to collapse to about half the full length for easier transport. Multiple stops make the poles adjustable length. The joint is near the middle, the weakest part of the pole, but 1″ steel conduit is pretty strong, and the overlap generous to take up much of the slop between EMT sizes.

The adjustable poles get just long enough to tension your tarp.
Round wire locks pin the poles at desired length.
Note how poles needn’t touch each other? Tensegrity design has compression members floating in tensioned lines.



In Mike’s words, edited:

Maximum length of each pole is 9’6″ and collapses down to 5’4″. Materials added up to about $50 provided you already have tools, hammock setup, and some 550 paracord.

Parts:

  1. Two: 10′ x 3/4″ EMT
  2. Two: 10′ x 1″ EMT
  3. 550 paracord (used to attach the two points that touch the ground together. As well as button knots on a loop, like MeyersTech ties, to run though the 3/8″ holes attaching the poles together.) This will likely be replaced by Amsteel or webbing over time.
  4. One: 1/4″ PEX tubing (I found a 5′ length to buy but I only needed 1.5″ or 2″ per hole in the EMT to create a bushing so the paracord is not cut by the EMT. I had to heat the end of the PEX over a candle to flair it out.)
  5. Various hammock straps and lines to attach the hammock and tarp
  6. Eight: Rubber Leg Tips. I used 3/4″ tips for the 3/4″ tubing but I would likely buy 1″ tips if I make it again. Then I used 1-1/8″ tips for the 1″ tubing. Then I placed 1″ and 1-1/4″ fender washers inside the rubber leg tips so the EMT tubing does not cut through.
  7. Four: 3/8″ x 1-5/8″ Round Wire Locks. These are to secure the telescoping poles at various lengths while in use and in the compact mode for transportation.

I used the 9’6″ set up for my 12′ tarp, and it worked great, but a shorter pole length would also work. If you keep the two poles that touch the ground at 90° to one another, the following table of pole lengths will be a good estimate of ridgeline (hypotenuse) length. There is plenty of wiggle room here, but it gives you a starting point.

Pole Ridgeline
9.5′ 13.4′
9′ 12.7′
8.5′ 12.0′
8′ 11.3′
7.5′ 10.6′
5.5′ 7.8′
Tensa4 is our trademark, Mike! We call other builds tensahedrons (tensegrity+tetrahedron).

Want another EMT version that packs even smaller? See US soldier Kamileon’s build.

Other approaches

In addition to steel, DIY tensahedrons have been made from wood, bamboo, fiberglass, aluminum, and carbon fiber.

The pole material determines the necessary diameter for enough strength. For about 300lbs in the hammock, 3/4″ is adequate for most steel including EMT conduit. 1.5″ is likely enough for aluminum. Wood and bamboo can be very beautiful, but as irregular natural materials, it is important to select carefully: 2 inches is a prudent minimum for clear wood (no knots, straight grain) or structurally sound bamboo.

The poles must be joined at their ends into a diamond shape, with none of the joints having fixed angles, but instead floppy, permitting the poles to assume any angle, and to rotate at least several degrees. We favor rope loop connectors as simple and field serviceable, but various combinations of hardware and even lashing can also work. Avoid using hardware that can put bending moment on the poles when loaded, such as eye bolts protruding from the sides of the poles: poles should be in pure compression, lines in tension.

Joints along the poles can be points of failure, especially near the middle. Best to use either very strong materials, split into an odd number of segments, or both. (Tensa4 poles are divided into 7 segments, with the largest diameter in the middle).

Why are we telling you this?

As a company, our focus is on products offering value beyond what people can easily make for themselves. Why promote cheap alternatives to buying our stuff?

Apart from us doing all the work, burdening nobody with the task of reading long blog posts, the special value of our Tensa4 stand is how we’ve made it pack so small and light: carry-on airline luggage, easy to pack on a bike with a motor or not, in a subcompact car, Cessna 150, kayak, or even a backpack. We realize that this amount of portability isn’t worth the price to everybody, especially large families seldom far from large vehicles, scout troops, extremely cool small national armies, or people who want only a home solution. We truly love helping people get off the ground with hammocks, especially where they couldn’t without this design.

Meanwhile, we figure the more people embrace the basic design, the more interest may turn to our packable dialed-in version, in 28 segments of custom made telescoping aluminum, keyed and anodized, not available at Home Depot. Quite a few of our customers, in fact, made one or more stands themselves before buying Tensa4.