RE: Light but Durable lightwind Cam sail - does it exist?
I agree with PG here.
If you want more durability, get X-ply. It's really no heavier than straight
monofilm, size for size.
The Sailworks Retro is a perfect example.
Older Retros used 6 mil (.006") thick monfilm in the larger panels, and still use that thickness in some of the small clear panels.
When the designer moved to using X-ply (due to market pressure from the number of other sail brands that began using it, not from any percieved durability issues) he found that the weight of a "composite X-ply sail film" could be reduced to the same as a single thicker piece of monofilm.
The 6 mil panels were replaced with a composite film of 2 layers of 2 mil
film bonded together over the reinforcing "x-ply" thread reinforcements, so the finished sail came out without gaining any significant weight.
The big advantage to X-ply and other reinforced composite films is that any hole that develops only affects the tiny squares (or diamonds) that they end in. Tears and cracks/creases only affect the damaged area where the reinforcements are cut/broken, and the damage does not propagate further across the entire panel of the sail.
Also the "glue layer" around the fiber reinforcements can be chemically compounded to reduce UV degradation. As a further advancement, aluminum film has been included to stop the UV degradation completely.
UV resistant single layer film is available but extremely expensive.
But I agree that you may be taping simple creases in your Tush sails that are nothing more than a cosmetic problem.
Most of us only use tape on a sail where there is an actual hole that extends all the way through the material.
The tape is there to hold the cut panel to it's original shape (as much as possible) and to prevent the tear from propagating further across the panel.
Hope this helps,