Nosefish Dome Deck

[email protected] · Post by **[email protected]** » Thu Feb 08, 2007 5:02 pm

I've designed and built a deck on top of my 2v "optimal" dome, with a 1v dome over the deck for a shade structure. I made a web site with pictures and instructions in case anyone wants to build a deck on their dome:

http://www.timefold.com/domedeck

If you decide to build one, drop me a note and let me know how it went, or if you run into problems with the web site. I'm at [email protected].

Peace,

Howard

MikeVDS · Post by **MikeVDS** » Thu Feb 08, 2007 6:25 pm

That's awesome. I hope someone is willing to make one for our dome. We'll see if anyone picks up the project. I posted your link to our forums.

timburly · Post by **timburly** » Thu Feb 08, 2007 10:22 pm

We're building a 32 foot 4 V dome. Any idea how much weight it can handle in the middle? I deck would be cool but i don't know if that would be safe...

timburly · Post by **timburly** » Thu Feb 08, 2007 10:30 pm

speaking of decks has anyone built a freestanding tall deck? Like somthing around 20 feet high?

[email protected] · Post by **[email protected]** » Thu Feb 08, 2007 11:12 pm

My design uses the top pentagon. The top pentagon on a 4v of a given diameter is much smaller than the top pentagon of a 2v of the same diameter. Your 4v is pretty big -- twice as big as my 2v, so I'd guess your deck will end up being approximately the same size as mine. Just guessing.

You didn't mention what material you're using. I'll assume it is 3/4 EMT. I am curious why you are building a 4v -- it is a heck of a lot of work.

A couple years ago my camp decided to build a big dome, and we were ready to make a 3v 5/8 dome 28' in diameter using 3/4" EMT. Then Tara of desert domes pointed out 1" EMT is 4 times stronger than 3/4" EMT. She suggested we build a 2v 28' dome out of 1" EMT. We did. It was incredibly strong and plenty big enough. And, my camp put the thing together in about 90 minutes. We made the struts in one day (took about 5 hours -- we had a crew of 4 experienced dome builders).

However, the top pentagon on that 28' 2v is *huge*. You could certainly build a deck on it, but my design is probably not adequate because the radial deck struts (those right under the deck) would probably be too far apart. I'm relying on the stiffness of plywood, and over such a long distance the plywood isn't as stiff. So, I don't think my design would work on that large of a top pentagon. Just as a reference point, my deck happens to fit a 4x8 sheet of plywood almost perfectly. When I put the sheet on the deck, I just have to cut off some corners. It spans the entire deck's width. If the top pentagon were any bigger, a single sheet wouldn't cover its width and you'd have a much harder time making a rigid deck. The design is really intended for a 2v optimal dome, or any dome with a similar or smaller sized top pentagon.

I've built and own a 3v, and I rarely use it anymore...

As for strength, any of the domes we're talking about here could certainly support 4 people on the deck. I recommend against testing the limits because the failure mode will be fairly catastrophic, and people falling from 16' will probably get hurt pretty badly. But domes are really strong once they are complete, and the deck design I made distributes the weight over the entire top pentagon and center bolt. From there, the weight is transferred into each of the connecting struts. So, if you had 1000lbs of people, plywood, 1v shade dome and shade cover (plus chairs and a few beers) up there, each vertex of the top pentagon is only taking 200lbs, and it is transferring that weight to at least two other struts each, so it is sharing that load. A good rule of thumb is that you can hang from any vertex in your dome and it won't hurt the dome. I'm not saying you can put a person on *every* vertex, but a vertex that is allowed to transfer load to neighboring struts can easily support a 200lb person. Thus, I see no problem with the dome deck supporting 1000lbs, and hence 4 people, with a suitable safety margin (so you can bring up a couple of beers each).

Oh, and you're going to need an 18' ladder (if it goes straight up) just to reach the deck and get on top. Kinda scary up there... but what a view!

Best of luck!

capjbadger · Post by **capjbadger** » Fri Feb 09, 2007 1:26 am

Funny enough, I basicly built the same thing last year. A 1v wood dome built on my 2v EMT dome. The deck pieces and 5 wedge shapes with plywood risers on the outside edges. One of the wedges actually extends out of the top dome to form a outside deck and ladder. You have to climb the ladder to get to the door with is on the 2nd floor. A hatch in the floor of the top dome's floor and a ladder gets you into the lower dome.

I'll have to see if I can dig up some pics for ya'll.

Badger

capjbadger · Post by **capjbadger** » Fri Feb 09, 2007 2:05 am

Older photos before the outer deck was reinforced and the ladder was put on the deck edge, but you get the idea. (Starplates for the upper dome)

robotland · Post by **robotland** » Fri Feb 09, 2007 5:32 am

Nosefishdomedeck! Nosefishdomedeck!

....I even like saying that more than "clothe the five minutes after skeleton"!

NOSEFISHDOMEDECK!!

Nice work, and kudos for posting the detailed step-bys.

Post by **AntiM** » Fri Feb 09, 2007 7:18 am

nosefishDoomeck is how it comes out when I try it. dang. and Bucky would love to visit.

[email protected] · Post by **[email protected]** » Fri Feb 09, 2007 7:29 am

That is a very cool design, capjbadger. I particularly like the way you've suspended the deck from the 1v struts -- saves a lot of structure. How heavy is the 1v made from wood? It looks very substantial. Well, it looks like the dome deck is an idea that has been thought of before. I am actually kind of relieved. It means that there is some existing evidence that domes can support the weight of a deck and the people on them. Again, clever design!

capjbadger · Post by **capjbadger** » Fri Feb 09, 2007 9:59 am

Thank you Hoco. I'm pretty happy with it. Once I put the carpet is, it was pretty damn comfy.

I actually have two different systems in those pics for suspending the floor plates. Both you can see in the first pic.

One way was attaching a 2x4 to the 1v struts with long square U bolts, and then the deck rest on that and the "nose" of the wedge in the top on the EMT dome.
It's a pain..

You have to drill the holes in the 2x4 just right and at the right angle. bah. It's so much easier with the 2nd method. You get the floor plate up there, place the nose on the top center, lift the tail end, and slap the plywood support in. Easy enough to do with one person.

The second method is sooooo much easier. It's just a piece of 3/4" ply. It sits on the strut and on the cups formed by the starplates on the bottom (which have been bent to bolt to the bottom dome). Since the 1v walls lean out a bit, and pressure from the floor plate above pushes it outwards against the vertical struts, so it can't come out.

You literally would have to lift the floor and then push the support inwards to get it to fall. Very safe and stable.

All the 2x4s you see on the bottom of the plates are just "framing" to stiffen the floor. The 3/4" ply is too weak by itself to span that gap. (about 4') Specially if the dominate grain of the ply is the wrong direction (found that out quick! lol)

The 1v isn't all that heavy. Not sure since I never weighed it. But the bottom 3/4" EMT dome took all the wood and three people and gear sitting up there without so much as a wiggle.

The deck that hangs out was stiffened with some more 2x4 framing and then two 2x6s get bolted on the end. Cross beams of 2x4 attach to the 2x6s to stablized the supports and doubles as the ladder.

It looks very substantial.

hahaha.. yeah, I tend to overbuild a bit sometimes, but for the playa I know it won't be going anywhere when I'm not looking.

Actually I can't take full credit for the idea of stacking domes and decks. Robotland's 3 tier dome (3 different sized 2v domes) that I saw in '05 gave me the idea to stack. Took the concept and ran with it.

Badger