An apparatus for the repair or maintenance of a papermaking headbox has two devices, one of which is used on the tending side and one of which is used on the drive side of the headbox. Each device has three parts, a lower bracket mounted to the headbox frame, an upper bracket mounted to the headbox slice beam, and a carriage which moves on a track formed on the lower bracket. The carriage is adjustably mounted to the upper bracket, and supports the slice beam which is attached to the upper bracket, and allows the slice beam to be precisely raised and lowered with respect to the headbox, so as to disconnect the slice beam from the headbox. Once separated, the slice beam is moved on the track, displacing it in the machine direction from the head box.