ways of preventing movement when desired and appropriate markings scales detents or other methods of aligning the various parts aspects of this invention perform straight cuts in brittle building materials by fitting a circular blade 16 to the power saw 14 and rotating the saw bearing 40 to make the circular blade 16 parallel to the direction of travel of the linear stage 20 along rails 26 and then positioning the circular blade 16 laterally and vertically with respect to the workpiece 50 the rotary stage 22 is locked and the workpiece 50 is then moved into the circular saw blade 16 with the linear stage 20 to achieve a straight cut fig2 is a plan view of the tile cutting device 10 of fig1 set for a straight cut fig4 a is a plan view of the workpiece tile 50 with straight cut 60 arcuate cuts are performed by first fitting the power saw with a plunge type blade 18 the power saw 14 is rotated on the saw bearing 40 to make the plunge type blade 18 perpendicular to the surface 28 30 of the workpiece the blade 18 is positioned in cooperation with the linear stage 20 to place the blade 18 in relation to the center 52 of rotation of the rotary stage 22 and the linear stage 20 locked this permits cutting arcs of arbitrary radius the workpiece is then positioned on the rotary stage and the plunge type blade is lowered by the arm lift bearing.