What's a Solid Starting Point for Feeds and Speeds When Turning Titanium?

Titanium turns best at low surface speed and a relatively high feed rate compared to steel, the opposite instinct from most machinists' first pass at it. Start conservative on SFM, keep the feed healthy enough to avoid rubbing, use plenty of coolant, and adjust from there based on your alloy, insert geometry, and machine rigidity.

Why titanium behaves differently

Titanium alloys, including the Grade 5 (Ti-6Al-4V) commonly machined for aerospace and medical parts, have low thermal conductivity. Heat generated at the tool tip doesn't dissipate into the chip and workpiece the way it does in steel or aluminum. It stays concentrated right at the tool. Run titanium at steel-like surface speeds and you cook the tool fast, no matter how good the insert is.

Titanium also work-hardens readily, and its low elastic modulus means the material springs back more under the same cutting force than steel does. That's part of why light, rubbing cuts hurt more than firm ones. A feed rate that's too light lets the tool dwell against work-hardened material instead of shearing cleanly through it, which accelerates wear.

Where to start

Surface speed needs to stay well below where you'd run 4140 or 1018 in the same operation. Think in terms of a substantial reduction, not a minor tweak, because thermal conductivity is the dominant limiting factor, not hardness.

Feed rate, by contrast, should be kept firm rather than light. A moderate depth of cut with a positive, sharp insert geometry works better than trying to finesse titanium with tiny cuts.

Coolant is not optional. Flood coolant, ideally high-pressure and directed right at the cut, does the job the material's own conductivity won't. It carries heat away from the tool that the chip and part won't carry on their own. Dry or lightly misted cutting shortens tool life dramatically.

Rigidity matters more here than in most materials, because titanium's tendency to work-harden means any hesitation, chatter, or interrupted cut leaves a harder skin the next pass has to fight through. A rigid setup with minimal tool overhang, inserts changed proactively rather than run to failure, and steady feed rates will outperform a delicate approach every time.

The practical takeaway

Treat titanium as a heat-management problem first and a hardness problem second. Keep surface speed conservative, keep feed rate firm enough to shear rather than rub, flood the cut with coolant, and don't let a worn tool linger. Titanium punishes worn tools faster than most materials because the heat has nowhere to go but into the tool. Your insert manufacturer's data sheet for your grade and coating is the final word on exact numbers. What's above is the starting posture, not a substitute for that chart.