Cutting Parameters for PCD & CBN Tools: Speeds, Feeds and Depth of Cut

August 16, 2026 · Exactalloy Technical Team

Speeds and feeds are a starting point, not a gospel. Use the table below, then let the chip tell you which way to adjust.

Quick answer: For PCD and CBN cutting tools start at vc 80–150 m/min in steel and fz 0.02–0.08 mm/tooth depending on diameter, with ae 25–40 % D and ap up to 1×D in roughing.

Read the chip

Silver, curled, 6-shaped chips mean the parameters are right. Blue or powdery chips mean too much heat; a thin ribbon means too little feed.

Radial vs axial engagement

Trading depth for width usually raises tool life. High-efficiency milling uses small ae (5–10 %%) with large ap (1–3×D).

Coolant strategy

Flood, through-tool, MQL or air blast — choose by material and depth rather than by habit.

Tuning loop

Increase feed first, then speed. If the tool chips, reduce speed and keep feed to avoid rubbing.

Specifications at a glance

Material group	vc (m/min)	fz (mm/tooth)	Note
Carbon / alloy steel	120–200	0.03–0.08	Flood or through-coolant
Stainless steel	60–120	0.02–0.05	Never dwell — work-hardening
Cast iron	150–250	0.04–0.10	Dry or air blast
Aluminium	300–800	0.05–0.15	High speed, polished edge
Hardened steel >HRC45	40–90	0.01–0.03	Small ae, rigid set-up

Frequently asked questions

Should I reduce feed when the tool squeals?

No — squeal usually means too little feed. Increase feed and reduce speed to stop rubbing.

How much depth of cut per pass?

Roughing ap up to 1×D with ae 25–40 % of D; finishing ae 5–10 % of D with ap 0.1–0.3 mm.

Get a quote and technical support

Exactalloy supplies PCD and CBN cutting tools from stock, made-to-order and reground. Send your drawing or specification for a quotation and lead time within 24 hours. Contact us or browse all products.