CNC Processing Team Completely Transforming Precision Cutting

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  What decides whether precision cutting works
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  How precision cutting technology removes material
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  Five-axis work and where it stops making sense
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  Materials that hold ±0.005 mm and materials that fight it
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  From file to finished part: the workflow a processing team runs
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  Applications where the cutting process decides the outcome
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  Which cutting route fits your part

Precision cutting is a sequence of planned cuts, each one removing a defined amount of stock and leaving a surface the next cut can accept. On a 5-axis machining center, the tool stays in contact through a continuous path while the rotary table turns the part. That means a curved surface can be cut in one pass instead of a series of straight steps with visible joints.

The cutting tool matters as much as the machine. For aluminium 6061-T6 we run carbide end mills with a polished flute and high helix, which clears chips fast at 8,000–12,000 rpm. For 17-4PH stainless we drop to 2,000–3,500 rpm with coated carbide and flood coolant, because the material work-hardens if the tool rubs instead of cuts.

Chip evacuation decides whether the finish survives. A recut chip under the tool edge will scratch the wall you just finished. Through-spindle coolant and air blast keep pockets clear. On deep cavities we program a peck path so the tool does not pack chips into a corner.

The last pass is the one that counts. A finishing cut of 0.1–0.3 mm radial depth at a feed that keeps the tool loaded produces Ra 0.8–1.6 μm on most metals. Polishing or bead blasting changes appearance, not the underlying geometry.

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  Rough first, then semi-finish, then finishThree distinct passes with a consistent stock allowance of 0.3–0.5 mm before the finishing cut.
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  Keep the tool engagedA tool that rubs instead of cutting raises heat and pushes the wall out of tolerance.
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  Match coolant to materialFlood for steel and titanium, air blast for aluminium and plastics.

A simultaneous 5-axis center moves X, Y, Z and two rotary axes at the same time. That lets the tool reach the back of a part without releasing the vise. On an engine mount or a manifold, that turns six setups into two, and every setup you remove is a tolerance you keep.

Five-axis is not free. Programming takes longer, the machine hourly rate is higher, and the rotary table has a size limit. Our 5-axis centers carry a Ø400 mm rotary table, so a part that fits that envelope can be cut in one flow. A part that does not fit should move to a 3-axis or 4-axis machine with a larger travel.

For flat plates and simple pockets, 3-axis is faster and cheaper. A 27-machine 3-axis group handles those parts at lower cost. Using 5-axis on a part that only needs three axes adds setup time and money with no accuracy gain.

The decision rule is simple. Count the faces that need machining. One or two faces, use 3-axis. Three to five faces on a part under Ø400 mm, use 5-axis. Long parts up to 4,000 mm go to a large-travel machine, where the geometry is usually prismatic and 3-axis work is enough.

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  Small, complex, multi-face partSimultaneous 5-axis, one or two setups, tight positional tolerance held.
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  Long prismatic partLarge-travel 3-axis, up to 4,000 mm, stable and economical.

Aluminium 6061, 6082 and 7075 cut clean and hold ±0.005 mm easily on features under 100 mm. They also move after machining if the stock was not stress-relieved. On a thin plate, we rough, let the part rest, then finish, so the internal stress releases before the final cut.

Stainless 304 and 316 work-harden under a dull tool. Use a sharp coated carbide cutter, keep the feed per tooth up, and never let the tool dwell. 17-4PH in the H900 condition cuts well and reaches Ra 0.8–1.6 μm with a light finishing pass.

Titanium TC4 (Ti-6Al-4V) and Inconel cut hot and slow. Tool life is short, so cost per part is higher. We run them when the application needs the strength-to-weight ratio, not because they are easy.

Plastics behave differently. POM and PEEK hold tight dimensions, but ABS and PP flex under clamping pressure and spring back after the vise opens. For those, light clamping and a finishing pass with a sharp single-flute cutter keep the wall straight.

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  6061-T6Best all-round choice for tight tolerance and fast cutting.
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  304 / 316 stainlessHolds tolerance if the tool stays sharp and the feed stays high.
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  TC4 and InconelReachable, but slower and more costly per part.

The workflow starts before the first cut. A DFM review checks wall thickness, tool reach, corner radii and datum choice. If a 2 mm internal corner needs a 2 mm cutter, the tool will deflect and the corner will not clean up. A 3 mm radius costs less and holds better.

Quotation and DFM analysis come back within 12 hours. That window is short because the review is a standing step, not a queue. Once the drawing and tolerance stack are agreed, production can start within 24 hours.

Machining runs on 127 high-precision CNC machines across three wholly-owned plants covering 7,600 m², with 150 technicians. The mix includes 16 simultaneous 5-axis centers, 12 four-axis mills, 27 three-axis machines and 16 mill-turn centers, plus a Singapore factory for regional delivery.

After cutting, parts go to finishing and then to inspection. Anodizing, electroless nickel, zinc plating, powder coating, black oxide, bead blasting and laser marking all run in-house. Laser marking holds a minimum character height of 1.5 mm, so a part number stays readable after coating.

Inspection is 100% before shipment. It covers incoming raw material, in-process checks and a final dimensional report. Reports are available on request. For a part that must hold ±0.005 mm, the report is the record that proves it did.

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  12 hoursQuotation and free DFM analysis.
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  24 hoursProduction start after drawing approval.
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  3–5 daysTypical shipment window for machined parts.

In aerospace prototyping, a bracket often carries a curved flange and lightening pockets on the same part. Five-axis cutting holds the flange profile and the pocket depth in one setup, which keeps the datum shared. A multi-setup route would stack two positional errors.

Medical device housings and instrument frames need a clean surface and a tight bore. Ra 0.2–0.8 μm is reachable with a fine finishing pass and polishing, and the bore can be held with a boring head after milling. ISO 13485:2016 process control covers the traceability side.

Automotive and EV parts such as motor housings and battery tray brackets combine aluminium bodies with steel inserts. Cutting both on the same route, with the insert bore finished after the aluminium is machined, avoids a mismatch at the press-fit joint.

Robotics and automation frames are usually long and thin. They need flatness more than tight hole position. A large-travel machine with a stable fixture handles the length, and a stress-relief step between roughing and finishing keeps the rail straight.

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  AerospaceCurved flanges and pockets in one setup.
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  MedicalFine finish and traceable process control.
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  RoboticsLong frames held flat through stress relief.