Geodesic Dome Construction (Tips and Tricks)

[regionalchaos]

The barrel makes sense. I had heard that building from the top down lends itself to bending struts. Something about the weight of the whole dome coming down on one or two struts. Using the barrel might relieve that however. Only having one tall ladder definitely was a disadvantage. We plan on having two that size out on the playa.

[geekster]

Yeah, the key is spreading out the load. We wait until everyone has arrived and set up their personal space then put the dome up after dark with the entire camp helping out. It went pretty fast last year, say an hour and a half or so. Once you get people on it and you get the order of the struts down, you end up with a train of people bringing struts to the people bolting them and some more people passing out nuts and bolts, etc. If you get into a groove, it goes up in a hurry.

[falk]

Would that work? Are there any calculations possible to figure out how much weight those connections can withstand?

If you attach at the vertices, they can take a lot. We had several sling chairs and hammocks suspended from the vertices of our dome. 3/4" conduit.

If you tie off to the middles of the struts though, they'll bend.

[falk]

The barrel makes sense. I had heard that building from the top down lends itself to bending struts. Something about the weight of the whole dome coming down on one or two struts. Using the barrel might relieve that however. Only having one tall ladder definitely was a disadvantage. We plan on having two that size out on the playa.

If you lift the dome from its center point while you build it top-down, the entire dome will try to fold itself in half. If you lift from the sides (bunch of people standing around the perimeter), it works much better, but you waste a lot of labor by using them as human jack stands. For a large dome, it's probably just best to go bottom-up.

The barrel method probably works great for a small dome. Don't know about a large one.

I know one person who built a 16' dome upside down, then just flipped it over. He was able to build the dome single-handedly.

[regionalchaos]

Large and Small seem like very relative terms in this conversation. How are you quantifying them?

[capjbadger]

[quote="falk"]

If you lift the dome from its center point while you build it top-down, the entire dome will try to fold itself in half. If you lift from the sides (bunch of people standing around the perimeter), it works much better, but you waste a lot of labor by using them as human jack stands. For a large dome, it's probably just best to go bottom-up.
[quote]

Umm... what??? I watched as a 60' dome was built top down with a crane attached to the to 5 vertices. No folding, no problems. For small dome, you can build bottom up, but for the really big ones, its just not the way to go.

[timber mischief]

I build 30' and 16' domes from the bottom up. for a 30' you'll need 1 piece of scafold to stand on and a 6' ladder to put on top of that fto work on the top of the dome. Or a 12' ladder and a good sence of balance. ( i've done both) The trick is to keep the sides balanced as you build, if you build to high on one side the dome will change into and eliptical shape and you'll have to pull on the offending vertecie with a rope to bring it back.
On a 30' once the first ring is complete and tightened, add struts as you would tighten lug nuts on a wheel. move to the opposite side to add the next vertical struts. Of course if you've got some pull with dpw itis easy to build while the dome is suspended from a crane or cherry picker.
Happy building : )

[capjbadger]

Yeah, building bottom up definately need to be build evenly. I just go round and round, adding struts, but keeping them loose, then once they are all on, starting from the top and tightening the nuts. Keeping it a bit loose when building bottom up lets you give the unfinished dome a shake to get the struts to line up.

I think the big dome I saw hanging from the crane was being built by DPW.

I never did see if they tried to cover it..

[falk]

Umm... what??? I watched as a 60' dome was built top down with a crane attached to the to 5 vertices. No folding, no problems. For small dome, you can build bottom up, but for the really big ones, its just not the way to go.

That must've been something to see. I know that my 32' dome folded pretty badly the first time we took it down. The next time we assembled it, we wound up cross-bracing it with ropes to keep it from folding.

I also saw the 36' dome across the street start to fold while it was being assembled.

The folding process goes very slowly; it's not sudden at all. What happens is that you notice that the dome is nearly touching the ground at two opposite points, and six feet in the air at the 90° points. If you don't act when you notice this, the dome will fold itself. I don't remember if I got a photograph of the result, but it wasn't pretty.

The simplest solution is to have people grab the low points and lift them up until the bottom of the dome is even again. Or to cross-brace with ropes as we did.

I'm amazed that someone built a 60' dome top-down. The only 60' dome at Burning Man I ever saw was the one that Pacific Domes brings, and that was built bottom-up.

[Lysergic]

Any thoughts on cheap efficient covers and perhaps good glues?

[regionalchaos]

Any thoughts on cheap efficient covers and perhaps good glues?

My current plan is used billboard vinyl. LyinBare, some kind soul I found on tribe, sent me a few page word doc that goes over heat sealing billboard vinyl with a standard clothing iron.

I'm starting to get curious about tyvek however. Does anyone have any opinions on this? Can I sink a grommet into a few layers of tyvek without having it rip out in 70mph winds? Billboard vinyl seems sturdier.

Regardless of the material, I'm planning to make hexagon and pentagon patches, putting grommets at the vertice ant bolting it to the frame. Do you think I'll need to add grommets for stitching it together in order to distribute the force applied by the winds?

[mamagrrl]

Yeah, but the source for Billboard vinyls has pretty effectively dried up, so consider other stuff.
If someone out there can source 'em, please msg me offlist. I could use one or two.

I saw someone with a pvc hoop-building using tyvek for their cloth. It looked really sturdy. (the stuff just doesn't rip!)

[AntiM]

I'm starting to get curious about tyvek however. Does anyone have any opinions on this? Can I sink a grommet into a few layers of tyvek without having it rip out in 70mph winds? Billboard vinyl seems sturdier.

Our snow camo is made from tyvek. It shreds in the wind if it is touching anything. Works spread and stretched out using the loops that are sewn in, but we had big holes in the one we tried to use as a draped canopy on top of a wood frame. It also rubs in transit, we had my art heads wrapped in it and they all ended up with white tyvek finishes!

[capjbadger]

Thanks to Robotland for the idea to stack domes, except mine is a 1 freq dome stacked on the old 2 freq dome.

15ft tall. My neighbors must wonder where the hell it sprung from since it wasn't there when they went to bed, but it was the next morning.



These "StarPlates" kick ass!

[system error]

ello there, im new here, been looking for a geodesic dome help forum for a while, and never though of looking on the nurbing man forum.Doh!
Anyway im building my 1st dome here in UK 3/4" conduit and 2v--2.50m radius..
Im busy getting my tools together abd I have 2 questions i need help with ok>>>>>

1. I bought a old drill press for $7 :wink: but it will only take a 4mm drill drill, is my best plan still to use the press to make the initial holes, and then work my way up to the correct size using an electric drill?

2. Im looking to buy an arbor press, but not having a lot of spare cash a 1 ton one is all i can aford. Will this be up to the job of crushing the conduit
or do i need 2 --3 ton press.

Thanks for all the tips i read already, super happy i found this place incase i run into problems.bOOOM!

i love desertdomes site
this is very valuble info! all newbies chek it! :arrow: :arrow:

[robotland]

Thanks to Robotland for the idea to stack domes, except mine is a 1 freq dome stacked on the old 2 freq dome.

15ft tall. My neighbors must wonder where the hell it sprung from since it wasn't there when they went to bed, but it was the next morning.



These "StarPlates" kick ass!

BRAVO! I'm delighted to have provided inspiration. And I gotta get some of those Starplates. I'm thinking about making a little geosphere treehouse.....

[Ugly Dougly]

Starplates kick ass! You could pre-drill everything at home and get it up on the playa in seconds.

No enough frequencies for some, but it's a dandy structure.

The Chicken Company for Easy Domes

[capjbadger]

Starplates kick ass! You could pre-drill everything at home and get it up on the playa in seconds.

No enough frequencies for some, but it's a dandy structure.

The Chicken Company for Easy Domes

Yeah, they're great. Just make sure all your 2x4s and the same lenght, drill the holes a 1/2" from the ends, and slap it together. Its sooo easy.

I had to do a little math to get it to match up with my current EMT dome so I could stack them, but still so easy.

Its too bad they don't make similar plates for 2 and 3 freq domes.

[Burp!]

We built our first dome in 1999, which was destroyed a year later in the great storm year of 2000. Built a new higher frequency dome the following year (Smoochdome) and have had that one ever since.

Things I've learned:

Having a map and someone who understands that map is essential, having two people better. That person's sole job is to hand you the correct pole as you need them. Color coding is a big plus.

Building top down to me is alot easier. We've done both approaches and have found it quicker and easier.

You must have a tall ladder to balance the center on as you go higher. The dome will not cave in on itself.

Having 4+ drill guns with multiple batteries will make the whole process a breeze. As the vertices get tighter and harder to put together the drill gun will fix that instantly.

Use eye hook bolts here and there rather than your standard bolt, this way you can hang stuff.

Get your group to commit to building this thing early on aka assign roles. People get to the playa and want to go adventuring, sometimes getting the commitment to complete the dome quickly is not there. Get that commitment up front. Set expectation. With 6 people committed to building, we were able to build our dome in about and hour and a half.

For coverage I suggest something darker up top for shade protection and something lighter down below so you can see out. If people can't see in they tend to be less likely to visit. If you can't see out, you miss the action. for the lower half we use that mesh stuff that is used for tennis court nets. You can buy remnants for pretty cheap online. for the top we use a hot air balloon top, which you can get for free(a tip to the guy running the shop is nice) from a balloon verification, not sure what the right word is for it, basically where they make sure the balloon is fit to fly. They will cut the balloon up if not, so there are pieces lying around for the taking. there is a shop in Oakland, the guy has boxes full of tops for the picking. He's flown his balloon to Burning Man so is burner friendly.

Make half moon air vents in the top for airflow, else have knives handy to cut your top loose if the BIG WINDS come. In 2000, we had to shred our dome top to keep the dome from rolling down the playa and killing people

Rebar, Rebar, Rebar. You must rebar it down, see above

Have a few extra polls and bolts, just in case

Email me if you need any other info/tips etc.

[falk]

Wow, that's a gorgeous dome. How big is it? You built it in 1.5 hours? How did you suspend it for top-down construction, and how did you keep it from folding?

[Burp!]

It's a 30' x 15'

Like I said if you have the commitment from your members to get it done as soon as possible after arriving on the playa, it can be done fairly quickly (depends on heat and weather of course).

I find that the building goes real fast if you have people dedicated to specific jobs.

Map Guy #1, he carries the map around and makes sure that the right polls are being connected together.

Map Guy #2, backup to Map guy #1, if for some reason Map guy #1 is gone, he can take over. Between the two they place the next polls to be used in front of the next vertices to be put together.

For each vertices being worked on you need a drill gun guy(drill guns are much better than hand ratchets, be sure to have lots of charged batteries available), and two guys to get the ends lined up on the bolt. As soon as you get the enough thread on the bolt exposed to get the nut on, the drill gun guy tightens it down. The drill gun does all the hard work of aligning the ends of the struts to the bottom of the bolt. Once the three guys get in a groove it goes real fast. If you have multiple groups of three working, it goes even faster.

For top down construction we typically use a tall A frame ladder to balance the dome on once it gets high enough that you need the dome higher. Typically as we go up we start to stack milk crates on the ladder to get more height.

Folding is typically a non issue as the dome is pretty sturdy pretty quickly. The thing to avoid is having weight on polls that are not connected crossways at the bottom. Still not really an issue as long as you don't let the weight bend a vertices inward. This is all pretty apparent once you start building. If you balance the center on the ladder you just connect it up and let the ladder bares most of the weight.

Make sure to have your map, something like this http://www.desertdomes.com/graphics/dome/4vdiagram.gif

Then just color code the polls. We put color tape on the ends to match the diagram

If you have any questions or need some tips fell free to contact me tspringett@gmail.com

I think we still have some the equipment we used to cut, flatten and drill the poles. Would be willing to loan that out if you need them.

T.

[falk]

Thanks for the advice. My dome is already finished (and in fact, my tools are out on loan to another dome builder right now.)

My layout diagram can be seen at http://www.efalk.org/OasisDome/layout.gif

I'll have to reconsider top-down construction if it worked so well for you.

[capjbadger]

Bit of a dome update...


Bottom of the flooring (with the door open)


Overhead shot (You can see the "deck" a bit)


Wide angle

Little bit more work and I'll be ready to start cutting the vinyl for the cover... Oi.. lol

[robotland]

Comin' right along there, Badger! Seeing your update pics reminds me of a discovery that you and/or others may find helpful- There were a few struts (in my version of what you're building) that happened to be placed where I and others were perpetually tempted to use them as steps...This would be bad, of course, and they were already starting to show some buckling. I cut lengths of 2x4", long enough to rest OVER the bolts on both ends of the struts, and secured them with 1" drywall screws through five evenly-spaced plumbing pipe straps. (Even though it was 3/4" conduit, I used the 1/2" straps so they'd be extra tight.) The reason for having the wood overlap the ends is to prevent the 2x4" from rotating- Downside being that you have to install it AFTER the dome's built, or else you can't get to the hubs! I compromised for on-playa, and brought short pieces of wood to cross-connect slightly shorter reinforced struts with by way of bolts. Stabilized with 2x4", the struts will flex slightly but bear the weight of a big guy (trust me!) right in the middle without incident.

[capjbadger]

Funny you should mention that. Every time I climb the ladder to the 2nd floor, there is a emt strut that just screams to be stepped on. I had the same idea to basicly "cover" it with a 2x4 to case someone stepped there on the way up.

[robotland]

...I thought I recognized something, in your pictures.

[Taritay]

I have been working on my own dome this spring and I finally have all the work done. It is a 20ft diameter 5/8 3v dome made of 3/4" conduit. I am completely tooless myself so I had to borrow almost all the neccessary tools. All the pipe was cut with a crank pipe cutter, all the ends flattened by hand with a sledge, and all the holes drilled with a 3amp corded drill and a stepping bit. I have atempted to set it up once, but unfortunately it started raining so we had to take it down. I don't belive we will experiance tooo many problems setting it up though, we should have more then enough people to make it easy. We have a couple parachutes that we are planning on useing for shade and if they are not enough then we will use sheets or whatever else we can strap down. Will probly end up putting down blankets or something on the inside. I wanted to hang a net of some sort halfway up or so to create a second floor, but I had to leave for the summer and didn't have time...next year. Anyways...I hope some of you will end up chilling in my creation and thank you so much too everyone who has posted...it really helped alot to hear from people with experiance...well...see you on the playa....

[jross]

What is the small diameter electrical or plumbing size pvc to use on a 1v style dome on the playa?

[roastduck]

Good morning, campers!

So, I'm a first-timer, planning my [ideally] 2012 trip (worst case, 2013), and i'm wanting to build a 24' diameter 5/8 3v dome out of 3/4" galvanized steel conduit. Since the height of it will be about 15 feet, i plan on having a sort of loft in the middle. Perhaps on a free-standing platform, but the idea of suspending it intrigues me. I also think it would be neat-o to put a deck on top from which to gaze upon my surroundings. am i setting my sights too high? Will the dome be able to support both of these structures?

After reading this thread and doing some research, i would suspend the loft from the vertices of the top pentagon, with guy wires going out to the sides to keep it from twisting about. (should i end up sleeping up there for some reason, i'd want it to be as stable as possible, since i sometimes do calisthenics in my sleep). The deck would be on supports coming of from the circle of vertices directly below the top pentagon. Is all this possible, or am i doomed to an embarrassing end??

Also, do you generally use your dome as you personal camp, or as a sort of common room for a large group of people?

[Bob]

I'd stick to hammocks and hanging chairs.