Occasionally twist can develop in any boat built without forms and a strongback. Here's a technique, called winding, allows you to quickly check that your kayak is straight.
Before taping the hull seams, make marks on each sheer clamp exactly 4 feet from the tip of the bow and from the tip of the stern. Place a straight edge or short board on each set of marks perpendicular to the keel line. Stand a few feet in front of the bow and sight down the centerline. Squat down until the bow straight-edge appears to "touch" the stern straight-edge.
If the straight-edges don't appear exactly parallel there's a twist in the hull. If you spot a twist, have a friend hold one end of the hull firmly while you "untwist" the other end.
