Abstract: A rotary sanding apparatus, includes a circular support plate having a relatively deformable circular ring extending from its front face to form an annular container and reinforcement for a resilient deformable foam pad. The front face of the pad is essentially coplanar with the front edge face of the circular ring, so that an abrasive disk can lie flat against the pad front face, with its outer edge area secured to the circular ring. The circular ring acts as a confinement device for preventing the foam pad from being torn apart by pressure engagement of irregular surfaces against the abrasive disk material.