A chuck adapted to clamp a workpiece (7) during wood turning. The chuck comprises a body (3), at one end attachable to a lathe (1) and at the opposite end having two radially opposed eccenters (8, 9) with equal eccentricity. Each of the eccenters is encompassed by or encompasses a clamping jaw (5, 6) respectively, which are recessed together to form a mutual end surface. The clamping jaws are arranged to be rotatable half a turn in relation to the body (3), wherein they together at one rotational end position form a cylindrical dics, and at the other rotational end position are radially displaced in opposite directions in relation to themselves.