If you cut your lines down you will have an 18' set - all you need to do is put a loop on the ends and make sure they are equal length. When I cut mine down I didn't even bother sleeving the cut ( kite) ends, I just tied a loop and coloured the loops red and blue respectively with some Sharpie marker pens! The sleeving doesn't weigh much, but in zero winds every little helps. For a winder for the 18' set I just used a winder from an old $5 single line kids kite I had in the garage - it even fits in the Prism case!