Great Pattern site...

[Vpicone]

http://www.jugglingdb.com/compendium/sk ... rt%20I.pdf

has anything from 3 - 16 pannel in either the tirangle or oval type patterns they also have varients of each so you could make a 4 pannel bag then experiment and decide if you want a 2 1/2 diameter or maybe 2 3/4 diameter. Works great for four pannels.