Finishing Operation: Diameter Compensation

A compensation factor for the final diameter must be used in the final machining operation. After the initial grooving to the required final diameter, the machining direction is normally changed for longitudinal turning. At this point the deflection occurs. If machining continues without correction, corner A will penetrate the material. This will result in two different diameters: øD1 from the grooving and øD2 from the turning. The difference between øD1 and øD2 is a value we define as ∆. The compensation factor is ∆/2, as shown below.


Using the compensation factor will eliminate the small surface step. Follow this simple procedure during machining:
1 Groove to the final diameter.
2 Pull the tool back,a distance equal to the value of Δ/2.
3 Continue the finish turning operation.


Characteristic values of Δ are shown in the diagrams on the next page.

• Characteristic values of Δ