Self squaring accident diagramming template

A portable template for making scale drawings of traffic intersections where first and second streets meet, the drawings comprising at least two curblines, each curbline comprising first and second segments corresponding to intersecting street edges and connected by an arc of a predetermined radius corresponding to a corner of the intersection to be drawn, said template comprising:

• first and second intersecting legs comprising first and second perpendicular inner edges enabling the drawing of the curblines, one leg inner edge enabling the drawing of the first segment of each curbline to be drawn and the other leg inner edge enabling the drawing of the second segment of each curbline to be drawn, the second segment of each curbline being perpendicular to the first segment thereof;
• at least one curved portion enabling the smooth drawing of said arcs between said first and second segments of each curbline;
• wherein the first leg comprises a first calibrated projecting slot means extending across it in axial alignment with the inner edge of the second leg, and the second leg comprises a second calibrated projecting slot means extending across it in axial alignment with the inner edge of the first leg, said first leg having a calibrated dimensioning slot means extending across it at a location between the first calibrated projecting slot and the free end of the first leg, said second leg having a calibrated dimensioning slot means extending across it at a location between the second calibrated projecting slot means and the free end of the second leg, said projecting and dimensioning slots means for establishing reference drawing points to which the leg edges may be thereafter fitted for proportionally drawing subsequent curblines;
• and
• a plurality of curved outer corners;
• and
• a plurality of cutouts defined in the template to be used as a guide for drawing traffic symbols, road markers, road signs, obstacles, and vehicles.

A method for making properly scaled and squared traffic accident drawings depicting intersections where first and second streets meet to form four curblines, each curbline comprising first and second segments connected by an arc of a predetermined radius, the method comprising the steps of:

• providing a portable template comprising:
• a first leg with a first edge and a second leg with a second edge, the first and second legs perpendicularly intersecting one another at a vertex;
• at least one curved portion enabling the smooth drawing of said arc between said first and second segments;
• a first calibrated dimensioning slot and a first calibrated projection slot defined in said first leg, the first dimensioning slot being spaced apart from and parallel with the first projection slot;
• a second calibrated dimensioning slot and a second calibrated projection slot defined in said second leg, the second dimensioning slot being spaced apart from and parallel with said second projection slot;
• and,
• a plurality of cutouts to be used as a guide for drawing traffic symbols, road markers, road signs, obstacles, and vehicles;
• and,
• constructing the accident scene upon a suitable sheet or form by executing the preliminary steps of:
• drawing a first line corresponding to the first segment of a first of the curblines to be drawn with said first edge as a guide;
• drawing a second line corresponding to the second segment of the first curbline to be drawn with said second edge as a guide, the second line perpendicular to the first line;
• without moving the template, drawing a first point within said first dimensioning slot corresponding to the width of said first street forming said intersection;
• without moving the template, drawing a third line within said first projection slot corresponding to an edge of said second street and forming the first segment of a second of the curblines;
• without moving the template, drawing a second point within said second dimensioning slot corresponding to the width of said second street forming said intersection;
• without moving the template, drawing a fourth line within said second projection slot corresponding to an edge of said first street and forming the first segment of a third of the curblines;
• without vertically lifting the template, rotating the template approximately 90 degrees so that said third line abuts said first edge and said first point abuts said second edge;
• without moving the template, drawing a fifth line through the first point against said second template edge, the fifth line comprising the second segment of the second curbline;
• without moving the template, drawing a third point within said first dimensioning slot corresponding to the width of said second street forming said intersection;
• without moving the template, drawing a sixth line within said first projection slot corresponding to an edge of said first street and forming the first segment of a fourth of the curblines;
• without vertically lifting the template, rotating the template approximately degrees from the last position so that said sixth line abuts said first edge and said third point abuts said second edge;
• without moving the template, drawing a seventh line through said third point along said second template edge thereby forming the second segment of said fourth curbline;
• without vertically lifting the template, rotating the template approximately 90 degrees from the last position so that said fourth line abuts said second template edge and said second point abuts said first template edge;
• without moving the template, drawing an eighth line through said second point along said first template edge thereby forming the second segment of said third curbline;
• and,
• finishing construction of the accident scene by executing, in any desired order, the final steps of:
• connecting the first and second lines to form said arc for said first curbline, thereby finishing the first curbline;
• connecting the third and fifth lines to form said arc for said second curbline, thereby finishing the second curbline;
• connecting the fourth and eighth lines to form said arc for said third curbline, thereby finishing the third curbline;
• connecting the sixth and seventh lines to form said arc for said fourth curbline, thereby finishing the fourth curbline;
• and,
• drawing a plurality of traffic symbols, road markers, road signs, obstacles, and vehicles upon said diagram using said cutouts in said template.