I made a Freeform Stretch Tent!

[Toe]

And the original that I copied from:

TLDR:
It works. Cheap, flexible, repairable. One person set up. Four way spandex, zigzag stitch seams (stretchy), 2"x2"x8 foot sticks (or larger bamboo) with protective mountain bike inner tube turbans. Secured with paracord (intentionally weakest point), tennis balls (fabric wraps around the balls), lag bolts. Big things can be dangerous in wind.



Set up:
-Stretch thoroughly to prevent flapping.
-Anchor corners first.
-Slipknot the fabric around the tennis balls with paracord.
-Paracord is intentionally the weakest point of failure.
-Tie cord to lags, pull tight.
-Put in support sticks every 10 feet or so especially along the perimeter. Careful not to stab through, but also shouldn't be loose.
-Adjust wall height, wall angle, supports to taste.
-In order to prevent falling supports, maybe tie supports to tent from outside of the tent somehow.

Ingredients:
-'Four way' 120% stretch spandex (AKA Lycra) jersey fabric in various colours and weights (can be found cheap on sale).
-Fabric wrapped around tennis balls (or bunched inner tube) and tied with paracord to secure points along the perimeter.
-Simple, single zigzag stitch (to allow for stretch) on each seam.
-Lag bolts every 5 feet or so.
-Supported by 2x2 x 8 foot lumber (or bamboo) with turbans made from mountain bike (wide, long, free) inner tube rubber to protect the fabric.
-Longer poles made by lashing poles together with inner tube.
-I used ~1.5 x 6 metre (5x20 feet) strips of fabric like this:
Original: 4 pieces sewn in roughly a square like this: llll
Expansion: 4 more 6 metre pieces added, two along each edge like this:
llll,ll
__
__
This left an open corner that made a nice entrance.

Performance:
-Cheap!
-Repairable.
-Totally silent (unlike flapping tarp)
-Covered 500 m^2 (1600 square feet)
-Fit in a big backpack (fabric only).
-Roughly comparable to aluminet.
-Versatile/flexible
-Expanded this year for 12 people, 7 tents, three vehicles (partial)
-Shade for four tents last year.
-Works better when seasoned with dust.
-Effective and comfortable.
-Easy set up with one person and without precision.
-Perforations did not propagate
-Resisted all wind in 2018 and 2019.
-Single point failures have not affected the overall structure.

Considerations:
-Machine washable as regular laundry.
-Unknown resistance to extreme wind.
-Supports can fall out when wind inflates the tent.
-Spandex/Lycra is rumoured to wear out after several burns, time will tell.
-'Trucker's hitch' block-and-tackle type knots can saw through paracord.
-Large sail area can be really powerful and dangerous especially with flapping, flying rebar tied to the end; hence the intentionally weak paracord and lag bolts (not rebar).

[Ratty]

I'm super impressed. I have spandex that's 20 feet wide from commercial factory. I may have to try this at some event. Thanks for posting. Good job.

If you screwed tennis balls to the top of each pole you could tie them to the fabric. It wouldn't completely prevent collapse unless you also secured them to the ground. Just a thought.

[Jackass]

That's cool, a small circus-like dwelling. Do you have a pic of it at full capacity?

[lucky420]

Very cool

[Elderberry]

Interesting idea.

[SnowBlind]

That looks pretty awesome. Where did you source that Spandex fabric? And if you don't mind, how cheap is cheap?

[Canoe]

Could we see closeup photos of the top of poles, fabric over top of poles and the guyline attachments?

[Ratty]

Snowblind, Try looking at the East Bay Depot for Creative Reuse. Telegraph Ave in Oakland. You may have to make several trips but it's a fun store. They usually have bolts of extra wide width. Cost...Somewhere between $1 and $4 a yard.

[SnowBlind]

Awesome, thanks for the tip, Ratty.

[evange106]

Do you have any closeup pictures of your fabric and seams? I'm guessing you used a double knit jersey with a high spandex content? In the areas that did get damaged, can you expand on (or show me) how that looked so I could maybe prevent similar from happening?

Also did you do anything special around the edges and corners? Like reinforcements or grommets?

You make it seem so easy so I'm seriously contemplating trying something similar, but that's a lot of wasted fabric and time if I'm misinterpreting.

[deepfried3ric]

We are considering doing a stretch tent for 2022. I'm envisioning something pretty much like what the OP posted. It'll be for the camp's lounge for us and visitors and will shade an area of about 15x20, maybe a little bigger. We have a carport kitchen and 1" conduit flattop for tents. Just want something with better aesthetics for the lounge. There are companies in South Africa that sell them, upwards of $1200. We have enough people chipping in so are willing to spend that if we have to, but if we can cut the cost without cutting the quality, we would. What I'm wondering is whether these can withstand the strong playa winds. The OP says they brought this in 2018 and 2019, but those years were rather mild. I'm thinking 2017 and 2015 (or was it 2016?) are the kinds of winds we need to anticipate. I don't see many of these structures... actually, I don't recall seeing any at Burning Man. Maybe this is why. Anyway, I'd love input, especially if you've got experience with this type of structure. We'd consider other Bedouin-type tents, too. I gather from my browsing that this is the concept used by actual desert nomads though.

It seems the center poles are held in place largely by the tensile strength of the fabric, which does give me pause. I imagine they'd need some sort of securing. We have HEAT come drill holes for our billboard posts so maybe we should consider doing that for poles for this as well. The last thing I want is something that is at high risk of collapse and poles hitting people.

[some seeing eye]

The South Africans are using custom fabrics that have some stretch are are waterproof. The clue for comparing fabrics if you don't have the technical specs is the fabric weight. I believe they are also using some very tough cable at the edge. I would strongly suggest a bungee stretch section in your guy lines. Those can absorb wind gusts. You can see my other posts on wind loading. There are specialty stores in LA that have wide fabrics for projection screens and theater curtains. Those aren't the South African fabrics. It is a good idea to research the UV resistance of fabrics, which can lengthen their life on the Playa and fire resistance is extra credit.

[gaminwench]

Shade does not equal UV protection.
I spent one 4Ju with heatstroke because the camp shade did not block UV, unbeknownst to moi.

[Toe]

@ evange106

Do you have any closeup pictures of your fabric and seams? I'm guessing you used a double knit jersey with a high spandex content? In the areas that did get damaged, can you expand on (or show me) how that looked so I could maybe prevent similar from happening?

Also did you do anything special around the edges and corners? Like reinforcements or grommets?

Ya it was pretty easy.

Sorry I don’t have detail pictures but here’s a bit more info.

Yes the fabric was a few varieties of knit jersey. I selected fabric according to three criteria; 1) that it stretched in all directions, and 2) that it stretched about 4x it’s relaxed length, and 3) that it was in the discount section at the fabric store (about $20~30 per person in a hiking-sized tent). Also I looked for a fun rainbow of different colours.

I used black fabric in one panel but it was too thin and proved to be the least shady part. So I guess thicker is a bit better.

Someone tripped on a guy line and fell through the fabric. They just sewed it back up with a simple whip stitch.

In high wind I got a bigger tear. It was tied to a car so maybe the car drove without untying. Dunno, I didn’t see it happen. Anyway. The repair is similar, any sort of stretchy stitch like a whip stitch or a zigzag stitch.

To prevent wind damage, put more support poles and anchors on the windy side.

Interestingly, even with a lot of the tent ripped, the rest of it stayed up fine. Such is the magic of a free form tent.

Also, the light weight poles meant that nothing got damaged when they fell over. It’s a safe-to-fail design, which is cheap to do. Rather than an expensive and heavy fail-safe design.

And people could put the poles back willy nilly even when drunk and high. No knowledge required.