The general recommendation for shroud line length is 1.5 times the diameter of the chute canopy. Since you usually use a length of string tied to the canopy at both ends and attached to a swivel or the rocket in the middle, each shroud line string you cut should be 3X the width of the canopy... that puts each end tied or taped to the chute canopy and the swivel or rocket tied on in the middle. I consider this as a basic minimum. One can go up to 2X the diameter of the canopy, which means each string would be 4X the canopy diameter when cut, with each end tied or taped to the canopy itself and the swivel or rocket tied on in the middle. There's really no advantage to going longer than that. The shorter the shroud lines, the more "scrunched" the canopy will be when opened (it won't fully inflate) and thus the faster the descent rate will be. In fact, sometimes folks will add a ring of tape to the shroud lines between the swivel or rocket and the canopy edge, taping them all together, to effectively "shorten" the shroud lines, to keep the canopy "reefed" (not allowing the parachute to open all the way to its full diameter, which increases the descent speed of the rocket under parachute).

Having used both methods of tying on shroud lines, (tying them all to two adjacent holes and then gathering them to the center, or 2) tying them all parallel across the canopy, and gathering them at the center) I can tell you that the second method works MUCH better and results in far less tangling and deployment problems. Regardless of the number of shroud lines (depending on if the parachute is hexagonal, octagonal, or round) the best way is to start with two adjacent holes, tie each end of a single line to them, and then tie the next line's ends to the holes immediately next to them, on either side of the first set of holes, and keep working one's way around the chute canopy until the last line is tied on to the last two holes in the edge next to each other opposite where you started... This method puts ALL the shroud lines PARALLEL to each other, which reduces crossed lines and tangling.

Best of luck! OL JR

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