What we do on a milling center

CNC milling is our workshop's default process — any prismatic part (one with mostly flat surfaces and pocketed features, as opposed to rotationally symmetric parts) starts here. We run 3-axis and 4-axis vertical machining centers from Haas and DMG MORI, equipped with through-spindle coolant, automatic tool changers holding up to 40 tools, and thermal compensation systems that keep accuracy stable across a full shift.

In practical terms: if your part is a plate, bracket, housing, manifold, enclosure, fixture, or structural component, it's probably made here. We also mill features onto turned parts, EDM blanks, and sheet-metal sub-assemblies — the milling cell is the connective tissue of the workshop.

3-axis vs 4-axis milling, and when to use each

A 3-axis milling center moves the cutter in X, Y, and Z directions. It can machine any feature that's accessible from a single direction — the top and sides of a pocket, through-holes, slots, face-milled surfaces. For most parts, a 3-axis setup with two or three fixture orientations covers everything.

A 4-axis center adds a rotary axis, typically letting you mill around the circumference of a cylindrical part without re-fixturing. This is cost-effective for parts with features on multiple faces (like valve bodies or shafts with keyways), because it replaces two setup operations with one program.

When to specify 5-axis

Specify 5-axis only when your part has features that can't be accessed from perpendicular setups — angled bosses, compound-curved surfaces, deep undercuts. 5-axis is more expensive per hour. See our 5-axis page for guidance.

§ 01 / Equipment

Milling machines currently in operation.

Machine Travel (X × Y × Z) Spindle Qty Typical use
Haas VF-2SS762 × 406 × 508 mm12,000 rpm · BT406Small & medium prototypes, aluminum production
Haas VF-4SS1270 × 508 × 635 mm12,000 rpm · BT404Larger plates, fixtures, enclosure halves
Haas UMC-500508 × 457 × 406 mm15,000 rpm · 5-axis2Mid-size 5-axis parts, aerospace brackets
DMG MORI DMC 850 V850 × 520 × 475 mm15,000 rpm · HSK-634Tight-tolerance steel & titanium production
DMG MORI DMU 50 (3rd gen)500 × 450 × 400 mm18,000 rpm · 5-axis2Complex 5-axis geometries, medical implants
DMG MORI DMU 85 monoBLOCK735 × 850 × 560 mm15,000 rpm · 5-axis2Large 5-axis titanium & aerospace work
Brother Speedio S700X2700 × 400 × 300 mm16,000 rpm · BT302High-speed small-part production runs
§ 02 / Typical milled parts

Examples of parts we mill every week.

CATEGORY · ENCLOSURES

Electronics housings

Two-part milled aluminum enclosures with gasket grooves, cable entry holes, PCB mounting bosses, and Type II black anodize. Volumes 50–2,000 pcs typical.

CATEGORY · STRUCTURAL

Brackets & mounting plates

Robotics linkage plates, sensor brackets, drive mounts. Usually 6061-T6 or 7075-T6 aluminum, with threaded holes, dowel pin locations, and alodine or clear anodize.

CATEGORY · FLUID POWER

Manifolds & valve bodies

Hydraulic and pneumatic manifolds with cross-drilled channels, O-ring grooves, and NPT or BSPP port threads. Pressure tested to 1.5× rated pressure before shipment.

CATEGORY · FIXTURING

Assembly jigs & fixtures

Precision fixtures for the customer's own production line. Usually tight-tolerance 7075 or tool steel, with hardened locating pins and wear plates.

CATEGORY · OPTICAL

Optical mounts & rails

Laboratory-grade optical hardware, lens tubes, beam splitters. Tight parallelism and flatness requirements, hand-polished bore interiors, blackened finish.

CATEGORY · HEAT TRANSFER

Cold plates & heat sinks

Liquid-cooled cold plates for EV battery packs and power electronics. Serpentine milled channels, vacuum-brazed covers, pressure-tested to 5 bar.

§ 03 / DFM guidelines

Design rules for cost-effective CNC milling.

01
Internal corner radii
Specify a radius equal to or greater than 1/3 the pocket depth. Sharp 90° internal corners require EDM or broaching. Standard minimum: 3 mm radius for pockets up to 10 mm deep; 5 mm for deeper pockets. Every additional finishing operation adds ~$10–$40 to per-piece cost.
02
Minimum wall thickness
In metals: 0.8 mm achievable, 1.5 mm recommended for production. In plastics: 1.5 mm minimum to resist cutting forces without deflection. Walls thinner than these thresholds can double machining time and fixture complexity.
03
Deep pockets
Pockets deeper than 4× the end mill diameter require step-down roughing and multiple tool changes, increasing cycle time. If you need a deep narrow pocket, consider widening it, or using a two-piece assembly with a bonded insert. Pocket depth:width ratios above 6:1 should trigger a design review.
04
Tolerance specification
Use ISO 2768-m for general tolerances (≈±0.1 mm). Apply tighter tolerances only to functionally critical features: bearing bores, mating surfaces, alignment datums. Specifying ±0.01 mm on every dimension triples inspection time and can add 30–50% to cost without improving part function.
05
Thread considerations
Tapped threads in 6061/7075 aluminum are reliable for M3 and larger. For high-torque assembly (M4 with >10 N·m preload), specify helical inserts. Metric (M-series) threads are faster to program than imperial (UNC/UNF) because tap stocks are more varied. Avoid specifying both imperial and metric in the same part.
06
Text & engraving
Engraved text is best at 5 mm or larger character height. For smaller text (down to 1 mm) use laser marking, which also produces higher contrast. Serif and thin-stroke fonts engrave poorly — use sans-serif bold faces for best results.

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