Calculate radial engagement and maximum step-over for step milling, so the cutter stays inside a safe engagement instead of taking a full-width bite.
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Request a Proposal βRadial engagement (step-over) determines how much of the tool diameter is engaged in the cut. Excessive radial engagement overloads the tool and causes vibration, while too little engagement causes rubbing and poor productivity.
40-70% for most steels with carbide end mills. Below 40% is inefficient (too many passes). Above 80% approaches slotting conditions and should use reduced feed. Aluminium can tolerate 60-80% at high feed rates.
Step-over is the primary determinant of cusp height in 3D surface machining. For ball mills: cusp height = step-overΒ² / (8 Γ tool radius). Halving the step-over reduces cusp height by 75%. For flat end mills, step-over has minimal effect on floor finish.
Scallop (cusp) height is the ridge left between adjacent tool passes. It is determined by step-over and tool nose radius. CAM software typically lets you specify maximum scallop height; it then calculates the required step-over automatically.
Enter your tool diameter and radial width of cut (step-over). The calculator shows the engagement percentage and the recommended maximum step-over. For roughing, keep engagement at 40-70%; for finishing, use much smaller step-overs.
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A stepped profile means two diameters ground on one body, which is a form tool, not a catalogue item. Send the pilot, the major diameter and the step depth.