Posted by Adam Tullis on October 29, 2009 at 10:43:25:
I am trying to verify the form diameter shown in table 57 of ANSI B92.1 - 1996 for an external spline with 17 teeth, fillet root side fit, 24/48 spline pitch, 45 degree pressure angle, with a class 6 fit. The table says the form diameter (Dfe) should be 0.679 however when I use formula 17.3 from table 105 (and a cf value of 0.001) I come up with 0.681. My confusion comes from the which value of form clearance (cf) should be used in formula 17.3. Table 2 indicates that form clearance is "0.0010, with max of 0.010, , min of 0.002" for all spline types covered by the specification. Does anyone know how this statement should be interpereted? Presently it doesn't make alot of sense to me the way it is currently worded since the value listed (0.0010) is outside of the ranges specified (0.002 - 0.010) in the same statement.