Orbital sanding pads won't stick if debris or tears in material are present. To replace the hook and loop / Velcro pad: Simply remove the three screws on bottom of sander to replace pad. Here is a link to a replacement pad. http://www.mscdirect.com/browse/tnpla/80...-Google-PLA+-+Test&CS_003=7867724&CS_010=80484868

(1) Internal components may be corroded (2) Terminals that the wires from sander are connected to may be loose or disconnected