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The initial resting pose of many industrial parts differs from the orientation desired for assembly. We show that it is possible to align parts during grasping using a standard parallel-jaw gripper. A solution is an arrangement of four gripper point contacts that will align the part in the vertical plane as the jaws close. Given a n-sided polygonal part and k uniformly distributed sample points on each side, we present an O(n4k4) numerical algorithm to compute a set of solutions or a report that no solution exists. The algorithm combines toppling, accessibility, and form-closure analysis. We have implemented the algorithm and report sensitivity data from physical experiments.