Geodesic Dome for Idiopolis

Participants
Skills	Mechanics, Muscles, Pipe Cutting
Status	Active
Niche	Hardware
Purpose	Infrastructure
Tool	No
Location
Cost
Tool category

Dome Construction 9.jpg {{#if:No | [[Tool Owner::{{{ProjectParticipants}}} | }} {{#if:No | [[Tool Cost:: | }}

Introduction

As Idiopolis, we have this super cool army tent at our disposal, but it's getting a bit flimsy, and it is not entirely sure how long it will survive. On top of that, all our party tent have been frankensteined into a mother of all partytents at haxogreen, but unfortunatly it has met its demise at the hand of the weather gods. I believe this provides us with ample arguments to consider a new construction for idiopolis, after all, CCC camp is just around the corner.

Proposition

I propose to build a geodesic dome to house our chaotic village in.

Pros:

Strong construction due to its nature
Durable
Broken parts are easily replaced
Spacious
And kinda cool
Few different kind of parts

Cons:

Lot of parts
Possibly heavy
Possibly bulky
Lengthy construction time

Construction of the pipe cleaner connectors

Start with two pipe cleaners, crossed in the middle.

Fold them across each other. For a 4-way connector (blue hubs in the construction diagrams), do this again and stop here.

Add a third pipe cleaner across the fold to form a crude hexagonal arrangement. For a 5-way connector, offset the lengths so one is shorter than the others.

Counting from the top clockwise, fold the first(2 o'clock) and fifth(10 o'clock) spokes around the sixth (12 o'clock).

Do the same for the the second(4 o'clock) and fourth(7 o'clock) spokes around the fourth (6 o'clock).

Rotate the entire structure clockwise by one spoke.

As above, fold the first(2 o'clock) and fifth(10 o'clock) spokes around the sixth (12 o'clock) in the opposite direction to before.

Finally, fold the second(4 o'clock) and fourth(7 o'clock) spokes around the fourth (6 o'clock) in reverse again to produce a 6-way connector (white hubs). For a 5-way connector (red hubs), loop the short end around the core and trim it short.

Strut construction

Cut:

50x 15.5cm tubes (A, purple in construction diagrams)
40x 15cm tubes (B, red)
30x 13cm tubes (C, blue)

Dome construction

-Things to remember:-

The dome only consists of two types of triangle - AAB and BCC. If you ever construct any that don't match these, something has gone wrong.

Start with a 5-way connector and put 5 C tubes around it. Tip these with 6-way connectors, and connect them with 5 B's to form five BCC triangles.

Add two A tubes to each of the outlying 6-ways leaving the last connection free. Connect these at the ends into five AAB triangles with more 6-way connectors.

Fill up that last space with B tubes, and end those with 6-way connectors. Join all the outlying 6-way connectors up with more A tubes to make 10 more AAB triangles.

Any 6-way with just A pipes to it, add two more A pipes. Any others, put two B pipes around it leaving the centre free.

Make 5 more 5-way connectors with all the remaining C-tubes and put one joining to the remaining spaces where the B-tubes join. Then use more 6-way connectors to join up the next outer pair and form 10 more AAB and 10 BCC triangles.

Connect the new 6-way connectors from above with a B-pipe. This will lift the dome a lot.

Fill up the remaining spaces on the 6-way connectors with only A's and B's by making sure that a B-pipe is never next to another B-pipe.

Join the ends of the new B's and C's with 4-way connectors, and A's and A's with 4-way connectors, forming 5 AAB and 10 BCC trinalges.

Join the remaining spaces up, connecting two BCC triangles with a B-pipe, and everything else with an A-pipe in an A-A-B pattern as you go around. Initially this will put a lot of stress on the freskly made joints, so on large scale make sure you have someone to help lift the dome with you as you complete.

Covering

I have prototyped a theoretical covering for the above structure consisting of hexagons and pentagons of 18cm side length. There seems to be enough slack with this ~20% extra space to allow for the centre dimpling of each polygon. On large scale this covering will need tying down somehow - I'd recommend constructing tiedowns on the triangular face joints. This ought to allow sufficient strengthening, and is possible to tie on if the above construction method is used, by constructing the whole thing underneath the covering.

Todo

Construction

Enumerate required tools
Acquire missing tools needed
Settle on size
Settle on tube diameter
Settle on linkage design
Determine total length of tubing required
Find supply of PVC tubing
Purchase materials
Cut tubes to required lengths
Build linkage
Create assembly plan
Assemble in back yard

Covering

Validate Hermetix as viable covering candidate. (go to supplier and visually inspect)
Decide on covering material
Determine how many hexagons and pentagons are needed
Calculate appropriate sizes for hex and pents.
Find supply of covering material
Extract required shapes from material
Decide on how to bind the shapes together
Create cool showoffy idiopolis artsy design for covering

A rough estimate based on a 10m dia dome, yields 256m2 of covering

Transport

Determine dimensions of a case or cases in which the dome can be transported
Create a design for said case(s)
Build case(s)
Find someone with a van/trailer/bus to transport the dome to germany

Ideas

Connector construction: [[1]]

Using steel CV pipe rather than PVC (heavier, but cheaper and stronger)
Using Hermetix as cover. E137,60 for a 50m * 8m roll

Useful links

http://www.cvtotaal.nl/cv-buis-22mm?utm_source=google&utm_medium=organic&utm_term=&utm_campaign=shopping&gclid=COWu88r5gsUCFcuWtAodl2IAuA

http://www.dekzeilenshop.be/nl-content1.asp http://www.deboerdrachten.nl/landbouwplastic-landbouwfolie/4682013/Landbouwplastic-Hermetix-50-x-8-meter-wit-groen/