2.Record data before and after stringing piano.

• The rest position (fully extended, which reads o.ooo”) of the dial gauge extends from the aluminum bar by 1” (1.000”)
• The Crownulator will therefore read a flat surface as 1.000”
• Any deflection will be the difference of 1.000” and the gage reading. A reading of .966” for example represents a deflection of .034” (1.000-.9.66=.034)

3.The radius in feet can be determined from the following formula:

R= {(H²+1/4C²)/2H}/12

Where: H = arc deflection and C = span of Crownulator

Where the span of the Crownulator = 12”, 1/4C = 36

Thus, a reading of .034 represents a radius in feet of:

{(.034²+36)/2*.034}/12

= 44.1191’

4.Calibration:

Each span is slightly different as a result of milling the stock square at the edges. You should therefore measure the span of your Crownulator and recalculate for the constant (1/4C²). You can then make a chart of readily available values or email with your exact span length and we will provide you with a chart.