Any ideas how to make new rotations?

[leesonlpn]

LPN's on our medical floor are trying to get a new rotation. Currently we work 7.4 hours, days and eves. No nights. Our day shift is 0700-1454. Eves is 1500-2254. We work a mixture of days then eves in our sets. Our sets are: 6 on, 2 off, 6 on, 2 off, 6 on, 2 off, 5 on 3 off, 5 on 4 off. Then it repeats. The girls are finding it very difficult to work 6 shifts in a row, and our sick calls are too high. We sometimes work 2 days, 4 eves, sometimes 4 days, 2 eves. Anyone have any ideas how to make up rotations, or is there some computer program that will nicely do all the thinking for us? We are willing to look at 10 hour shifts. Management feels there is not a need for lpn's on nights. The floor is staffed by 3 RN's for 25 patients.Any feedback gratefully apppreciated.