Opportunity is missed by most people because it is dressed in overalls and looks like work. - Thomas Edison
what's most important is to get the mesh square in the frame before you insert the locking strips.
The weft threads elongate less, those that run across the length of the bolt tube--this is the direction you want parallel to the long roller. The warp threads are those concentric to the tube you pull from--these should be parallel to the short roller.As I understand it, the weft threads are under more tension when the mesh is woven and heat set, so they elongate less under tension. By aligning these threads to span the larger distance, the elongation distance stays similar to the larger elongation of the weft across the shorter span, keeping your mesh openings square.Perhaps NRM is manufactured differently from Hitech, PeCap, or Murakami mesh and doesn't require this.