I ship sails everyday. Just find the biggest box you can. Flake fold the sails to fit the box and roll it loose from luff to leech. Be sure to be kind to the window.

DO NOT roll it first and fold it in half. It will do much more damage.

How does North ship 3DL's, how does UK ship Tape Drives, they flake fold.

What about the abuse of large headsails on racing boats, up and down, rolled in a ball every downwind leg.

Folding a mylar cat mainsail for shipping isn't going to shorten it's life.

The only fabric I won't fold is Dimension HTP+ (used in the Hobie 20 Jibs) Those need to be rolled, that fabric will tear if folded wrong.

Sorry to hear about your unfinished sail.

Chip Buck
www.whirlwindsails.com