Centreless grinding kinematics: What is the typical maximum angular adjustment range available for the regulating (control) wheel relative to the grinding wheel/workrest?

Introduction / Context:
In centreless grinding, the regulating wheel is inclined by a small angle to the workpiece axis. This angle controls the axial feed in through-feed grinding and affects stability and roundness. Machines provide a limited angular adjustment to tune process behavior.

Given Data / Assumptions:

• Standard centreless grinder with tilting regulating wheel spindle.
• Usual industrial ranges for through-feed operations.
• Angle is modest (small degrees), not tens of degrees.

Concept / Approach:
The regulating wheel inclination is commonly adjustable from approximately zero up to about 8–10 degrees, sufficient to generate the desired axial thrust without compromising contact geometry or stability. Excessive angle would cause control loss or chatter.

Step-by-Step Solution:

Verification / Alternative check:
Machine manuals and textbooks cite ranges like 3–8° or up to roughly 10°, aligning with option (b).

Why Other Options Are Wrong:

• 5° can be within range, but not a typical “maximum.”
• 15°/20°/30° are unusually large and impractical for stable grinding.

Common Pitfalls:
Confusing workrest blade angle with regulating wheel inclination; they are distinct setup parameters.

Final Answer:
10°