2V 1/2 sphere geodesic dome
Class I icosahedral breakdown, cut snapped to the nearest vertex ring (achieved portion 50%). 65 struts in 2 lengths, 26 hubs, 40 panels. Strut length = chord factor × sphere radius.
Open this geometry in the studio
Struts
| Strut | Qty | Chord factor | 12 ft dome | 16 ft dome | 20 ft dome | 24 ft dome | 30 ft dome | 40 ft dome |
|---|---|---|---|---|---|---|---|---|
| A | 30 | 0.54653 | 3' 3 3/8" | 4' 4 7/16" | 5' 5 9/16" | 6' 6 11/16" | 8' 2 3/8" | 10' 11 3/16" |
| B | 35 | 0.61803 | 3' 8 1/2" | 4' 11 5/16" | 6' 2 3/16" | 7' 5" | 9' 3 1/4" | 12' 4 5/16" |
| Total | 65 | 228 lin ft | 304 lin ft | 380 lin ft | 456 lin ft | 570 lin ft | 761 lin ft |
Cut lengths are hub-centre to hub-centre; subtract your hub's offset at each end.
Hubs
| Valence | Qty |
|---|---|
| 6-way | 10 |
| 5-way | 6 |
| 4-way (base) | 10 |
| Total | 26 |
Panels
| Signature | Qty | Area (unit R) |
|---|---|---|
| AAB | 30 | 0.1393 |
| BBB | 10 | 0.1654 |
| Total | 40 | 5.833 |
Proportions (per foot of radius)
- Height 1.000 × R · floor diameter 2.000 × R
- Surface 5.833 × R² · floor 3.142 × R²
Computed by DomeSketch from the icosahedral geometry; the 2V/3V/4V values match the published tables and the test suite asserts it.