Cup One vs Open Surf Spi RHN 58
How do the Cup One and Open Surf Spi RHN 58 compare? Below, their dimensions, displacement, sail area and the standard design ratios side by side, followed by a data-driven summary.
Cup One | Cup One | Open Surf Spi RHN 58 | |
|---|---|---|
| Length overall | 12.6 ft3.85 m | 12.6 ft3.85 m |
| Waterline length | —— | —— |
| Beam | 2.0 ft0.62 m | 2.2 ft0.68 m |
| Draft | —— | —— |
| Displacement | 35 lb16 kg | 44 lb20 kg |
| Ballast | —— | —— |
| Sail area | —— | —— |
| SA / Displacement | — | — |
| Displacement / Length | — | — |
| Comfort ratio | — | — |
| Capsize screening | 2.48 | 2.53 |
| Hull speed (kn) | — | — |
Cup One vs Open Surf Spi RHN 58: the short version
- The Cup One and Open Surf Spi RHN 58 are close in length (12.6 ft3.85 m vs 12.6 ft3.85 m ).
- The Open Surf Spi RHN 58 is heavier, displacing about 26% more, which usually means a steadier but slower-to-accelerate hull.
- By the capsize screening formula the Cup One rates better for offshore work (2.48 vs 2.53).
Ratios are guidelines computed from published specs; condition, layout and gear matter as much as the numbers.