Abstract: A mastic applicator and finishing tool is provided with a trowelling bar and means are included to adjust and regulate the pressure upon said bar so that the crowning of mastic applied by the tool, may be controlled. A sliding ramp component may be moved in side to side, each position being stabilized by the engagement of a cross pin or pawl within any one of a plurality of notches in the components which are situated at an angle to the base or to the trowelling bar of the device. Means extend between the pin and the trowelling bar so that each notch engages the pawl and applies different pressure upon the trowelling bar. The notches are identified by indicia for ease of ascertaining the setting of the ramp.