An accessory for an oscillating power tool includes an attachment portion configured to be coupled to an oscillating power tool and a working portion extending generally along a longitudinal axis. The working portion has a rear end portion coupled to the attachment portion, a front cutting edge opposite the rear end portion, a first side edge extending from the front cutting edge to the rear end portion, and a second side edge opposite the first side edge and extending from the front cutting edge to the rear end portion. The working portion includes an at least partially curved surface that contains the longitudinal axis. At least a portion of the first side edge includes a first side cutting edge portion.