point 43 from a piece of material 40 in accordance with an embodiment of the present invention to measure point 43 to be trimmed from material 40 a broadened end 17 of a planar structure 11 of tool 10 is sized so that broadened end 17 is the same width as the width of material 40 where material 40 should be trimmed to remove point 43 broadened end 17 of planar structure 11 is perpendicular to the elongate sides of planar structure 11 which are a straight edge 12 and a guide edge 13 in the preferred embodiment broadened end 17 is three eighths of an inch wide which is the width of a piece of material at the correct distance and angle from the vertex of a forty five degree angle to remove the dog ears in typical use of the present embodiment the user aligns lips formed by guides 14 on guide edge 13 of planar structure 11 with an edge of material 40 that forms the forty five degree angle broadened end 17 of planar structure 11 is located near the forty five degree angle of material 40 keeping one edge of material 40 aligned to the lips of guides 14 the user then adjusts tool 10 until broadened end 17 of planar structure 11 overlaps a width material 40 that is exactly the same width as broadened end 17 from edge to edge the user may then mark or trim the fabric along broadened end 17 of planar structure 11 referring to fig4 broadened end 17 of planar structure 11 comprises an edge 32.