Adding retrieval patches

I have a tramp launched spin sail that I want to add retrieval patches to so I can use it in a mid pole snuffer. Are there any rules of thumb I need to follow when adding patches? It's a large sail, goes with a Supercat 20 Tall Rig.

http://www.catsailor.com/forums/ubbthreads.php?ubb=showflat&Number=238485

Here is an older post on the topic.

Mac, what snuffer are you using? We had Dennis build a custom SNU for the 35 sq mtr spin on the 22, because it was too big for his standard shell. How big is your tall rig chute?

Dave

I don't know the sq ft/ft of the spin sail, but it's freakin huge! I had a custom SNU built for the standard mast spin, the bag is 12ft long!

Thanks Bach, I'll look at that thread