A snubber apparatus comprises a casing defining an inner cavity. A shaft passes through the inner cavity and rotates about its longitudinal axis. The shaft has one or two ends laterally projecting out of the casing and being connected to a moving part of a tool to dampen given motions thereof. A wiper arm is on the shaft so as to rotate therewith the shaft, with a free end in close proximity to the surface portions of the inner cavity. The free end has an arcuate contour complementarily corresponding to a circumferential surface portion. A dam extends from the circumferential surface portion into close proximity to the wiper arm, to divide the inner cavity in two chambers, with movements of the wiper arm changing the volume of the chambers. A hydraulic circuit controls a flow of fluid between chambers to oppose a force to rotation of the shaft.