If you head to one of Druid's old sietches (co-ords 19,22), you'll find an old fremen all west from the entry that wants to fix a windtrap. You'll need three parts for this, all inside chests in various sietches. First one is easy, as it's in the same sietch, just look in the various rooms for an openable chest. Second one is at 25,3 and third one at 60,12. Show up with all parts in inventory at Give the parts to the same fremen for 1 qp.