MANUFACTURING – CNC MACHINING CALCULATOR
Stepover Scallop Height
A precise tool.
What is the Stepover Scallop Height & How does it work?
In CNC machining, the scallop height (often called the surface finish) is the vertical distance between the theoretical surface and the actual machined surface. Keeping the scallop height low reduces post‑processing work and improves part performance.
For a ball‑end mill the relationship between the stepover (the lateral distance the tool moves between passes) and the resulting scallop height is governed by simple geometry. The tool radius R and the stepover f define a circular segment whose height is the scallop height h.
In practice the stepover is often set as a percentage of the tool diameter. By adjusting this percentage you can balance material removal rate against surface finish quality. The calculator below lets you compute the scallop height for any chosen tool diameter and stepover.
h = frac{f^{2}}{2R}
h = scallop height (mm), f = stepover (mm), R = tool radius (mm)
Parameters
Result
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Frequently Asked Questions
What is scallop height in CNC machining?
Scallop height is the vertical distance between the theoretical surface and the actual machined surface, representing surface finish quality.
How does stepover affect scallop height in ball-end milling?
A smaller stepover generally results in a lower scallop height, leading to better surface finish and reduced post-processing work.
What is the formula for calculating scallop height with a ball-end mill?
Scallop height can be calculated using the tool radius (R) and stepover (f), forming a circular segment whose height defines the scallop height.
How does increasing the tool radius affect scallop height?
Increasing the tool radius typically increases the scallop height, as it allows for larger cuts but may compromise surface finish quality.
Why is maintaining a low scallop height important in CNC machining?
Maintaining a low scallop height improves part performance and reduces the need for post-processing steps like polishing or grinding.
Can you explain the relationship between stepover and scallop height in ball-end milling?
In ball-end milling, reducing the stepover decreases the scallop height, which is crucial for achieving a smooth surface finish on machined parts.
What factors should be considered when setting the stepover for CNC machining?
When setting the stepover, consider the tool radius, desired surface finish, and material properties to balance efficiency and quality.
Results are for informational purposes only and do not constitute professional advice.