Abstract: A grinding tool for the inside of cylinder has a motor driven stem carrying a hub on which is a notched hub member detachably securing ends of three flexible legs. A shoe having a fixed grindstone is pivotally attached to each of the legs and is releasably held by a spring clip. A sleeve surrounds the hub member to help hold the legs in place. A nut secures the sleeve on the hub member. An annular flange is loosely fitted on the hub and is held by the nut to serve as a stationary hand grip while the remainder of the tool rotates.

Abstract: A reversible wrench has a handle integral with a ring shaped head. A reversing mechanism in the head includes a cup shaped member rotatable on a cam block carrying a tool holder. A rotatable control plate on the head has a depending pin engaged in a slot in an end wall of the cup shaped member. The cam block has an upstanding pin engaged in another slot in the end wall and contacting a leaf spring carried by the control plate. Slots in a cylindrical wall of the cup shaped member carry rollers adjacent the cam faces of the cam block. A finger grip on the control plate facilitates rotation of the control plate and rotation of the cup shaped member and rollers on the cam block to effect reversing action between the wrench head and the tool holder.