Questioning the "Spine" of monkey huts - I dont understand

[AliCat903]

So you had the centre pieces of your ribs attached to each other with the rope and bundled into the tarp, what did you do with the two side lengths? Were they bundled in too? That sounds like it would have been crazy heavy and awkward to get on and off a truck.

The side lengths were put in right next to the centers of the ribs and then rolled up along with it. It takes us 3 or 4 people to pick the whole thing up onto our shoulders and walk it out of the truck. So yeah, I suppose it's heavy, but it's so nice to have it all bundled up into one thing so we don't have to worry about losing parts. The only thing that isn't included in each bundle is the rebar with the paracord attached.

[Jovankat]

I can see how that would be convenient but it would have been super problematic for us with the way we packed our truck, all our PVC went in last on top of everything and into crevices. It may be useful for us now that we have a BRC shipping container though.

[inventory]

Been on vacation so late to this thread, but:
+1 to what MacGlenver and Jovankat said. Spineless designs can work.

My former camp successfully did rope substituted for PVC spine on both 30' circumference and 20' circumference huts for several years. We used:
- Amsteel for the rope (non-stretchy, which is key, & very strong)
- shade cloth on the 30' and tarp on the 20' (myself, I hands down prefer 80% or better shade cloth)
- clove hitches around ribs (to keep ribs from separating)
- Amsteel run off end of hut and down to carabiner on candy-caned rebar (acts as guy lines, also keeps ribs from compressing)
- rebar for guy line put on centerline of monkee hut, even if you use two rope "spines"
- On the guy line, alpine butterfly knot (to provide a loop), free end of line run down and through carabiner then back up through butterfly loop and down through carabiner again, then your favorite knot that can be untied for re-tensioning every two days.

Hardest part is getting a standard distance between ribs with the line. We tried tying all the ribs together on the ground the first year (hah! don't do that), then moved to tying it in the air but with a measuring stick (aka extra piece of PVC). Get first two ribs in the air and tie up, then anchor guy on that side. Move down hut length putting up ribs & tying them. At end, tie second guy. Go back and retension first guy, then retension second.

You want to cinch down until the top of the hut juuuuust starts to look oval rather than round. Don't smoosh it.

For the 30' circumference you likely need stabilizers like MacGlenver said. We used 2x4's with notches cut out wedged under the ribs on the interior of the hut on the windward side.

[maladroit]

You could have permanent measuring sticks (pieces of PVC) that hold the ribs apart an even distance, built into the monkeyhut structure itself. Run them down the length of the monkeyhut, sort of like a spine.

[inventory]

You could have permanent measuring sticks (pieces of PVC) that hold the ribs apart an even distance, built into the monkeyhut structure itself. Run them down the length of the monkeyhut, sort of like a spine.

Ooooh, I like it. Maybe even fasten them in somehow, so you don't have to hold them in the air while you tie a knot. PVC X-connector? Bicycle inner tubes?

[theCryptofishist]

If you don't have a spine it can't be a monkey hut. Chordata, and all that, you know. Of course with out a spine, it could be a jellyfish hut or even a segmented worm hut. So many phyla...

[burn_shady]

As can be seen by the answers, you can do it without a spine, but you need an alternative to it that has been designed to replace it. In practice, there are compressive forces that the spine is meant to resist in its role of keeping the ribs a fixed distance apart. Additionally, having a spine at the apex of the hut helps the structure shed water without the threat of it pooling (save it about it not raining at burning man, last year I was one of those stuck in line at the gate for 18 hours waiting for things to dry, it happens, it's a consideration). I think that what makes the question a head-scratcher is that the compressive forces are slight when compared to what other parts of the design must survive. Also, the original design had a very large diameter tube at the top, I don't think this was because they were anticipating a large force there. It was more about convenience, what size PVC would fit in another and the available fittings. The guys who use bicycle tubes to tie the ribs to a 1" spine were completely successful. I wouldn't go smaller than 1" for the spine, but unless you're taking other steps to replace the spine, it should be considered a required piece.

[kin]

Hi Folks.

I appreciate these replies. I just found out that were a couple since I last checked; I didn't notice the email update.

minor sidenote, I will deal with rain problems by the fact my hybrid tarp will have shade clothe on the top.

Hopefully early next week I'll put together my build. . It looks like it'll be very similar to a galaxy without spines but with amsteel (my favorite rope ever .)

[inventory]

amsteel (my favorite rope ever .)

Oh hey, another cultist enthusiast! I was converted to The Amsteel Way by Suspended Animation a few years back. I giggle knowing that my tie-down ropes have a breaking strength substantially greater than the pull-out strength of their anchors. (Which means the weak point is probably my knot-tying. )

[kin]

Bowline my friend! Another rope related thing to be cultist about .

But actually, finish it with an extra securing clove-hitch. Bowlines are beautiful knots but Amsteel is so incredibly slippery that I find it might slip a bunch before it gets into enough tension to stay put.

I'm cheap though, I'll be using amsteel for the 'spine' so it doesn't stretch out over the week, but cannot afford to use Amsteel everywhere :p.

[kin]

While I'm airing things out...I was playing around with the idea of using 1/2" EMT Alu conduit instead of 1" PVC pipe.
The numbers suggest the pipe might be similar flexible to the PVC pipe.
Stiffness of Alu:
69 Gpa, moment I = 0.00484 from .706 OD and .622 ID, E*I = .33396 (bigger = stiffer)
Stiffness of PVC:
2.9 Gpa
1" = 1.315 OD and 1.029 ID = 0.09158 moment I, E*I = .2655
So my calculations suggest the aluminum pipe should be only 25% stiffer than the PVC pipe.

But I went to home depot during lunch and played with the shit but found the alu pipe to be a shit-ton stiffer than the PVC pipe. :'(. So, kind of my fault for sitting in my chair doing calcs instead of being practical.

But, if anyone did have experience using 1/2" EMT Alu pipe, I'd love to hear it. I generally just like the fact I can do something with alu pipe afterwords moreso than I can with PVC pipe. Plus the Alu pipe is a couple bucks cheaper and small.

[Autumn_in_winter]

One thing you could try is use a collapsible spine (IE segments that connect with fittings in a line) then run a strap/rope down the center. Attach the ends of the rope/strap together outside the spine so it makes a giant loop. Then your can tighten the crap out of the strap to get a lot of compression on the spine so it doesn't come apart

[kin]

One thing you could try is use a collapsible spine (IE segments that connect with fittings in a line) then run a strap/rope down the center. Attach the ends of the rope/strap together outside the spine so it makes a giant loop. Then your can tighten the crap out of the strap to get a lot of compression on the spine so it doesn't come apart

Hmm, so what you're suggesting here seems to be the reverse of what I think I'll end up doing, but I want to make sure I understood you.

So you're saying: Keep the spine, but let's make it actually work in compression. Maybe even avoid some of the lines needed on the short-faces of the monkey hut, because you just keep things in compression instead?

Meanwhile I am leaning towards eliminating the spine, but pulling tension on the long faces, so the whole spinal region is in tension.

I don't think your idea is wrong it might work.

My biggest trouble with the threaded monkey hut, which does some internal compression stuff, is that it adds a good bit of complexity and extra parts to setup.

[vargaso]

One thing you could try is use a collapsible spine (IE segments that connect with fittings in a line) then run a strap/rope down the center. Attach the ends of the rope/strap together outside the spine so it makes a giant loop. Then your can tighten the crap out of the strap to get a lot of compression on the spine so it doesn't come apart

I did exactly this one year. You have to use 2 straps, one on either side of the connectors, so that the tension is even and doesn't bend the spine. It worked OK, although I wouldn't do it again.

[Martiansky]

I use a pvc spine using pvc x's and t's with 2' segments in between them and then the pieces are glued together.
The ribs are 10' long and join in a sleeve that slide into the spine.
All the pieces are wrapped in a tarp and ride up on top of my truck.

I would really like to make a bigger (XXL) monkey hut for the next trip to BM. One that would slide over the top of my dome and then still.big enough to sit under outside of it.
I'm going to toy with adding longer ribs and see what happens.

This is a very good thread with lots of info.
Thanks all!

[kin]

(response to martiansky): cool. I think you want to use spines and continue using spines, but are tickled by the thread's topic (which is in fact different than your way, which is the spine way.)

The spineless people will not complain. we are afterall spineless.


Posting on this thread much later now, I would say the spine-less bit worked, but my pre-measuring distances method sucked and I did a lot of adjustment. This was hard because I could barely reach when standing on my HDX tote, which was pretty cheap and thin to stand on for my ass (worked OK when full of items though) The biggest introduction of error was probably that my lag bolts were not very easy to align perfectly and maybe had I put more work into that then I would have fewer issues with the rope-spine.


Overall I was not as ethused by the monkey hut as I expected, because it was quite some work to setup and took up a lot more space than I wanted it to take up. I think since I used largely shade clothe (not entirely) i may as well have used steel EMT conduit for square-profile shade, but then again the sun's angle means I'd have to make that pretty big too for it to be useful. HMMM, I am agnostic at the moment. Shade is fucking great, but I didn't love the work it took to setup my particular monkey hut. Then again I was able to setup a 14'x23'x9' (approx) monkey hut with only moderate help from a single friend. This means while it was a PITA for me, it was not the craziest amount of setup work.

[Martiansky]

OOPS, Sorry I highjacked your thread, Kin!

I considered not using a spine but after a trial set up I opted to use one.
My sister and I lay out the canvas we use as a floor template, pound in the rebar, layout the pvc frame and then we each take a side of one rib and bend it up and onto the rebar. We continue with each rib.
One end butts up against the dome and the open end has a pvc flagpole which props up the end spine and then is ratchet strapped to ground.

Sorry you had problems with your hut assembly.....
What if you had a pre looped rope spine?
____O____O____O____O____

[trilobyte]

FYI - angled side tarps work well on conduit frame structures. Keeps everything shaded and deflects winds up and over the structure.

[Martiansky]

Hey Trilo,
That's a good idea!
Adds a little more floor space also doesn't it?

[trilobyte]

Yeah it does. In various years depending on how packed we were we've been able to get a couple extra tents in under the shade (keeping at least a foot between the tarp and the tent), or we use it as storage for bins/water, etc. I recommend using white for the side tarps (as opposed to silver), that helps keep the place from feeling like a cave.

[Jackass]

Some folks crave the cave, dark = cool, just sayin.

[trilobyte]

You're welcome to say or do whatever you want. My recommendation is based on many years of experience, and in recent years doing multiple structures each year. I've tried with white and with silver side tarps, silver isn't noticeably cooler but can be 'trip over shit in the middle of the day' dark.