CALCULATING CROWN MOLDING ANGLES

DIAGRAM 1
 Set the Select Entry Mode to Angle MAIN PITCH Rise : Enter the SPRING ANGLE ADJACENT PITCH Rise : Enter the SPRING ANGLE TOTAL DECK ANGLE : Enter the WALL ANGLE The Run fields are disregarded in Angle calculation mode. Click on the or button. Fascia Miter = Crown Molding Miter Fascia Bevel = Crown Molding Bevel EXAMPLE CALCULATIONS Inside Corner MAIN PITCH Rise = SPRING ANGLE = 38° ADJACENT PITCH Rise = SPRING ANGLE = 38° TOTAL DECK ANGLE = WALL ANGLE = 90° Fascia Miter = Crown Molding Miter = 31.61901° Fascia Bevel = Crown Molding Bevel = 33.86291° Outside Corner MAIN PITCH Rise = SPRING ANGLE = 38° ADJACENT PITCH Rise = SPRING ANGLE = 38° TOTAL DECK ANGLE = WALL ANGLE = 270° Fascia Miter = Crown Molding Miter = 31.61901° Fascia Bevel = Crown Molding Bevel = 33.86291° Irregular Corner MAIN PITCH Rise = SPRING ANGLE = 45° ADJACENT PITCH Rise = SPRING ANGLE = 45° TOTAL DECK ANGLE = WALL ANGLE = 135° Fascia Miter = Crown Molding Miter = 16.32495° Fascia Bevel = Crown Molding Bevel = 15.69986°

DIAGRAM 2

DIAGRAM 3

 If the Crown Molding follows an angle measured on the wall in elevation as per DIAGRAM 3 above the entries are made as follows: Set the Select Entry Mode to Angle MAIN PITCH Rise : Enter the COMPLEMENT of the SPRING ANGLE ADJACENT PITCH Rise : Enter the COMPLEMENT of the SPRING ANGLE TOTAL DECK ANGLE : Enter the angle measured on the PLANE of the WALL EXAMPLE CALCULATION MAIN PITCH Rise = COMPLEMENT of the SPRING ANGLE = 52° ADJACENT PITCH Rise = COMPLEMENT of the SPRING ANGLE = 52° TOTAL DECK ANGLE = Angle measured on the PLANE of the WALL = 120° Fascia Miter = Crown Molding Miter = 24.46355° Fascia Bevel = Crown Molding Bevel = 17.92855°

CROWN MOLDING FORMULAS
Example Calculations
 SPRING ANGLES are equal, the WALL ANGLE measured in PLAN is bisected (refer to DIAGRAM 1 ) MITER ANGLE = arctan (sin SPRING ANGLE ÷ tan WALL ANGLE) BEVEL ANGLE = arcsin (cos SPRING ANGLE cos WALL ANGLE) Alternate Bevel Formulas: (cos BEVEL ANGLE) ² = (sin SPRING ANGLE cos WALL ANGLE) ² + (sin WALL ANGLE) ² (cos BEVEL ANGLE) ² = (cos SPRING ANGLE sin WALL ANGLE) ² + (sin SPRING ANGLE) ² Calculate the MITER ANGLE first, and: BEVEL ANGLE = arctan (sin MITER ANGLE ÷ tan SPRING ANGLE) BEVEL ANGLE = arccos (sin WALL ANGLE ÷ cos MITER ANGLE) BEVEL ANGLE = arccos (sin SPRING ANGLE cos WALL ANGLE ÷ sin MITER ANGLE) BEVEL ANGLE = arcsin (tan MITER ANGLE sin WALL ANGLE ÷ tan SPRING ANGLE) Calculate the BEVEL ANGLE first, and: MITER ANGLE = arctan (sin BEVEL ANGLE tan SPRING ANGLE ÷ sin WALL ANGLE) MITER ANGLE = arccos (sin WALL ANGLE ÷ cos BEVEL ANGLE) MITER ANGLE = arcsin (tan BEVEL ANGLE tan SPRING ANGLE) MITER ANGLE = arcsin (sin SPRING ANGLE cos WALL ANGLE ÷ cos BEVEL ANGLE)

 SPRING ANGLES are equal, the WALL ANGLE measured in ELEVATION is bisected ) (refer to DIAGRAM 3 ) MITER ANGLE = arctan (cos SPRING ANGLE ÷ tan WALL ANGLE) BEVEL ANGLE = arcsin (sin SPRING ANGLE cos WALL ANGLE) Alternate Bevel Formulas: (cos BEVEL ANGLE) ² = (cos SPRING ANGLE cos WALL ANGLE) ² + (sin WALL ANGLE) ² (cos BEVEL ANGLE) ² = (sin SPRING ANGLE sin WALL ANGLE) ² + (cos SPRING ANGLE) ² Calculate the MITER ANGLE first, and: BEVEL ANGLE = arctan (sin MITER ANGLE tan SPRING ANGLE) BEVEL ANGLE = arccos (sin WALL ANGLE ÷ cos MITER ANGLE) BEVEL ANGLE = arccos (cos SPRING ANGLE cos WALL ANGLE ÷ sin MITER ANGLE) BEVEL ANGLE = arcsin (tan MITER ANGLE sin WALL ANGLE tan SPRING ANGLE) Calculate the BEVEL ANGLE first, and: MITER ANGLE = arctan (sin BEVEL ANGLE ÷ (tan SPRING ANGLE sin WALL ANGLE)) MITER ANGLE = arccos (sin WALL ANGLE ÷ cos BEVEL ANGLE) MITER ANGLE = arcsin (tan BEVEL ANGLE ÷ tan SPRING ANGLE) MITER ANGLE = arcsin (cos SPRING ANGLE cos WALL ANGLE ÷ cos BEVEL ANGLE)