Given an involutive negator N and a leftcontinuous t-norm T whose contour line C0 is continuous on ]0, 1], we build a rotationinvariant t-norm from a rescaled version of T and its left, right and front rotation. Depending on the involutive negator N and the set of zero divisors of T, some reshaping of the rescaled version of T may occur during the rotation process. The rescaled version of T itself can be understood as the β-zoom of the newly constructed rotation-invariant t-norm, with β the unique fixpoint of N.