3Di™ is a unique, patented sailmaking technology that allows laminated sails to approach the balanced loadbearing and shapeholding of a rigid airfoil. In simplified technical terms, 3Di is a flexible composite membrane built from spread filament tapes pre-impregnated with glue, arranged in multiple axes to form a membrane and then thermo-formed on a 3-dimensional (3DL) mold. Because filament tapes make up the entire surface of the sail, no film is needed to form the laminate.
With 3Di technology, designers have such precise control over the placement and orientation of material within the sail, they can come far closer to achieving balanced resistance to distortion in all directions. Less distortion = more drive.
Product Highlights
- Unique, patented technology using an array of spread filament tapes to form a composite membrane with no film
- Balanced resistance to distortion in all directions makes 3Di approach the performance of a rigid foil
- Available in Carbon / UHMWPE or Aramid / UHMWPE composite styles
Which upwind sail is right for you?
All Upwind Sails Page ►
Upwind Sail Performance Guide ► Learn More About 3Di
3Di Q&A ►
3Di Explained ► | 
A spread filament tape is an individual yarn that has been spread out until the individual filaments lie side-by-side, forming an ultra-thin "tape." Shown here is a pre-preg carbon / UHMWPE (Spectra/Dyneema) spread filament tape a mere 35 microns thick.
|