Here's a simple 1V version that uses bamboo slid into black garden irrigation hose offcuts. These are (single) gutter bolted at the hose overlaps -the structure is both rigid & quickly dismantled for storage. All 24 struts are of identical length & thickness.
Step 1: Big Kids - Smaller Kids!
Step 2: Dome Features
* Compared with rectangular buildings a key dome feature relates to their numerous triangles,which resist stress and greatly strengthen the overall structure, yet make it lightweight. Many dome designs however are intricate & may use struts of varying lengths. A few wonky struts or weakened joints can jeopardize the entire structure,much as happens with a cracked egg shell!
* Recall that a 2D circle contains the most area for the enclosing perimeter? A 3D dome,being near spherical, has the property of enclosing the most internal volume for the external surface area. Aside from reduced cladding costs, this feature is particularly valuable when thermal losses/gains need considering.
* Dome wind resistance is far superior to regular buildings - a particularly valuable atrribute for exposed positions (dome tents, hill top radar stations etc). See =>www.ecocamp.travel/Domes
* Snow loading & shedding abilities are greatly enhanced. The classic South Pole dome lasted ~40 years, and although it's base became well buried the "roof" remained clear. See =>.http://graphics8.nytimes.com/images/2009/11/10/science/10dome-span/articleLarge.jpg
* Rain accumulates at the dome base,requiring low level guttering which -although easy to clean!- may be unsightly.
* Human feelings of embracing security,along with novelty and expansiveness,often arise. "Roof" windows give privacy and may bring in valuable daylight & offer entrancing views of trees,birds,hills,clouds, sunsets,stars & the moon.
Although ideal for exhibition halls or short term events, dome homes however may have issues accomodating normal furniture & appliances, efficiently using small building sites (circles don't nest together well!), accessing utilities, providing regular windows & doors, circulating air or internally partitioning for privacy. As one user concluded "they're smart but not wise..."
Refer further dome insights => http://en.wikipedia.org/wiki/Geodesic_dome
Step 3: Traditional Kids Domes
Step 4: Simplest Dome
* 24 equal length struts (we've used 750mm long bamboo struts, but ~1m gives better headroom?)
* 11 securing points (irrigation hose offcuts,joined in "star" clusters with a single bolt,are used here)
Credit to https://www.jovoto.com/projects/300house/ideas/12565 for this lucid graphic !
Step 5: Visualising the Design
Step 6: Lolly Model to Full Scale
Note- the hose is normally very cheap, but irrigation fittings themselves can be quite costly. Unless you have an ambitious application in mind avoid hence using such "X", "T" & joiners.
When neatness,versatility and strength are important using such fittings can be justified however -refer my 433 MHz tape measure antenna Instructable =>www.instructables.com/id/433-MHz-tape-measure-antenna-suits-UHF-transmitte/
Step 7: Bamboo Strut Selection
Cat "Molly" shown on strut quality control duties.
Step 8: "Star" Joints
Step 9: Hose Cutting
In NZ this hose is usually sold in 20m rolls, so if you make ech hose offcut a shorter 130mm, then enough offcuts for 3 domes can be made + a few spare! . (130mm x 50 offcuts x 3 domes = 19500mm = 19½.metres, with. 500mm left over = enough for ~ 3 extras)
Step 10: Hot Air Gun Tab Creation
Step 11: Tab Drilling
Step 12: Securing Bolts- Rationale
Although tools are a magnet for budding engineers,many young kids become frustrated with screwdrivers & nuts and bolts. The dome design lends itself to assembly/dissassembly at these securing "stars", but this way is a tad fiddly & NOT intuitive. Bolts & nuts may become lost as well...
I've hence taken the approach of leaving the "stars" assembled (in 4 & 5 clusters), both for quicker erection/dismantling AND as intuitive "this looks to go there" visual aids.
* The downside of this is that undersized bamboo struts may annoyingly slip free unless taped thicker.
* An admirable upside is that longer struts (24) can be organised at any stage to simply slip into sockets to make a larger dome! It's hard to argue with that sort of flexibility!
Step 13: Taping Loose Struts
ALERT: Ensure the bamboo struts are not taped TOO tight of course, as otherwise they may be very hard to remove, only to suddenly pop out & injure someone nearby.
Step 14: Screws ?
Step 15: Assembly!
Step 16: The Bedtime Team at Work
Step 17: Cling Film Covering?
Such a structure can get very warm inside (perhaps TOO warm for kids), but it'd suit "lift off" cloche/greenhouse winter-spring garden duties, although securing/weighting would probably be needed to avoid wind damage & dome take off...
Step 18: RAPID Dismantling
Step 19: Smaller Cat Nap/dog Box Version
Step 20: Larger Versions?
The BoM (Bill of Materials) for the framework shown here is only ~US$10.
The improved door way access, greater headroom (~1700mm) and floor space (~2metres across) suits covering such larger domes for kids dens or sleep outs, and even possibly seasonal garden green/shade houses. Taller adults ( I'm 187cm) could be catered for with a low footing wall that'd elevate the dome up off the ground somewhat. This would improve drainage & also allow wind proofing if the lowest struts were secured to bricks or timber etc.
* Suitably sized galvanised mesh netting could be used as a screen to protect ripening crops from birds or poultry -or even pesky butterflies! (Pollinating bees,being used to tight hive spaces, could still get thru' bird netting mesh OK.)
N.B. Domes intended for longer term use (or likely kids hi jinks) should of course have heavier duty timber or metal struts that are firmly secured. These bamboo & hose offcut creations are really intended to stimulate youthful imaginations!