| Check | Why | |-------|-----| | Module vs. reference diameter | DIN 5480 uses ( m \times z ) = reference diameter, not pitch diameter | | Pressure angle | 30° is default; 37.5° / 45° change base diameter significantly | | Span measurement k teeth | Round k to nearest integer; wrong k gives wrong Wk | | Over‑pin formula | Requires inverse involute – use approximation or Goal Seek | | Fit class tolerance | Don’t ignore – affects functional clearance |
Implement Invα = tan(α) - α (α in radians) with iterative solver for α when measuring over pins. din 5480 spline calculator excel verified
Excel implementation: =TAN(radians) - radians | Check | Why | |-------|-----| | Module vs
Instead of building from scratch (risky for production), use : din 5480 spline calculator excel verified
Best practice: Re-verify after any Excel version upgrade (different calculation engine) or operating system change.