I always run my tip ups for pike but will be using them for walleye this weekend. On my tip up I run 30# tip up line, a lot of people don't like it because it absorbs water and freezes but I haven't had any problems where I couldn't stand it anymore and I like it because its a little thicker and doesn't seem to bite into your hand, with a 30# steel leader. For switching to walleye I left the steel leader on then took a 6-8 ft piece of 10lb flouro and tied a barrel swivel to one end and my treble to the other. I just clip the steel leader into the swivel and its good to go. I also added a dab of super glue to the knots to keep them from slipping.
Given I have not tested this set up out yet, but I think it will work fine. I was given some tips by a long time walleye fisherman on how to rig my tip up. It is exactly the way he told me with the addition of the steel leader for easy switches between pike and walleye. I'll post back once I've tested it.
Let me know what you guys think in the mean time. Thanks.