Yeah, I'm with Steve on this... most kilts (on guys with a 38" to 42" waist) have 27 to 35 pleats... an averagre of between .75" and 1" per pleat. I HAVE done a kilt with .5" pleats (42 pleats total) at the piper's request (he had to match the rest of the band). They looked WAY too small.

Since you are pleating to the stripe, you can choose WHATEVER pleat size you want (when you use the sett, sometimes the way the pattern is laid out dictates the pleat size). I'd go with .75" per pleat. It'll give you a nice tight pleat without being too small.

I hope this helps a bit.