fastener passes through window 68 and through an aperture in the periphery of saw guard 26 for reasons of mechanical geometry arising from placement of pivot pin 70 both window 68 and aperture 72 are preferably triangular shaped window 68 is furthermore larger than aperture 72 and is able to move from side to side in operation an external force is applied to window 68 causing it to pivot a desired distance in the direction of the force because window 68 is larger in size than aperture 72 the portion of window 68 previously covering the aperture can be exposed for cleaning as shown by the broken lines in fig9 fig1 shows another window assembly embodying the principles of the present invention in this embodiment a first aperture 76 in saw guard 26 is covered by a window 74 saw guard 26 is further provided with a second aperture 78 proximate and generally perpendicular to aperture 76 aperture 78 can be covered by a removable plug 80 in operation plug 80 is removed to enable a cleaning tool or compressed air to be introduced through aperture 78 to dislodge dust from the underside of window 74 fig1 shows another window assembly embodying the principles of the present invention in this embodiment saw guard 26 is provided with an aperture 82 a window assembly 83 is adapted to be coupled with saw guard 26 window assembly 83 is comprised of a transparent elongated planar element 84 having planar ribs 86 88 90 and 92 disposed longitudinally on and perpendicular to planar element 84 pivot pins 94 and 96 are located on opposite ends of element 84 along its longitudinal center axis pin guides 98 and.