ADCO CNC: The Person in Charge of Precision Parts

In most machine shops, a part passes through four or five hands: an estimator, a programmer, a setter, an operator, a quality inspector. Each one does their job well, and nobody can answer "where is my part right now" without opening a folder. That is fine for a bracket. It stops working when the part has a Ø12 mm bore held to ±0.005 mm, a thin wall, and a hard deadline.

At GreatLight the accountable engineer is assigned at quotation and stays on the job until the parts ship. That person reads the model, flags features that will be hard to hold, agrees tolerances with you before metal is cut, and signs the final inspection report. One name on the traveler. One phone number when something looks wrong.

This is not a sales contact who forwards your email. The engineer who owns the job can read a setup sheet, correct a toolpath, and tell you whether a 0.4 mm wall on 7075 will move after clamping. That last part matters more than the org chart.

The role is also a filter. If your drawing calls for a feature that five-axis can reach in one setup, the engineer will say so and quote it that way. If it needs three setups and a custom fixture, you hear it at RFQ, not after the first article fails.

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  Single name on the travelerOne engineer owns the part from RFQ through final inspection and shipping paperwork.
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  Drawing review before cuttingHard features, datum conflicts and tolerance stack-ups are raised before the first setup.
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  Direct technical contactYou talk to the person who programmed and inspected the part, not a call center.

Three-axis milling is predictable. The tool comes down the Z axis, the table moves in X and Y, and the geometry you can reach is limited but easy to fixture. Complex parts with angled faces, deep pockets on multiple sides, or contoured surfaces force a different decision: reposition the part several times, or cut it in one setup on a simultaneous five-axis center.

Every reposition adds error. Each new fixture has its own locating tolerance, each clamp cycle can distort a thin section, and each setup is a chance for a chip or a burr to sit under a datum pad. On a part with four angled faces, three setups can easily consume 0.02 mm of stacked variation before the tool touches metal.

GreatLight runs 16 simultaneous five-axis machining centers, 12 four-axis mills, 27 three-axis machines and 16 mill-turn centers. The five-axis group handles parts up to 4,000 × 400 × 150 mm on the large travel machines, with a Ø400 mm rotary table for parts that need rotation around a bore.

The catch is programming. Simultaneous five-axis toolpaths need post-processor work, collision checks and a programmer who knows what the machine will actually do at the corners. That is why the accountable engineer on a five-axis job is usually the programmer as well. Fewer handoffs, fewer surprises.

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  One setup, more facesAngled and contoured features are cut without repositioning the workpiece.
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  Less stacked errorFewer fixtures means fewer datum shifts between operations.
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  Programming is the bottleneckSimultaneous five-axis paths need post-processor tuning and collision checks.

Aluminum 6061-T6 is the default for prototypes and most housings. It cuts fast, holds ±0.005 mm on a rigid setup, and takes anodizing in clear, color, hardcoat or conductive form. The 7075 grade is stronger but more prone to stress movement after heavy stock removal, so the owner will typically rough, stress-relieve, then finish.

Stainless 303 and 304 machine cleanly; 316L and 17-4PH are common in medical and food-contact work but work-harden if the feed is too light. Titanium TC4 (Ti-6Al-4V) and Inconel 625 or 718 need sharp tooling, low cutting speeds and a tool-life plan agreed before the run starts. Magnesium AZ31B and AZ91D cut well but need chip handling rules on the floor.

Finishes are not decoration on functional parts. Electroless nickel and hardcoat anodizing both add a thin layer that can change a bore size by a few micrometres. If the drawing calls for a press fit after coating, the engineer has to adjust the pre-plate dimension. That conversation is part of the owner's job.

Plastic parts follow a different logic. PEEK and POM hold tight tolerances but move with temperature; ABS and PC are usually specified for enclosures where appearance matters more than fit. On those jobs the owner is often checking surface finish and laser marking layout rather than micron-level geometry.

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  Stress relief on 7075Rough, relieve, then finish to avoid movement after the last cut.
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  Work-hardening stainless316L and 17-4PH need adequate feed per tooth, not a light rub.
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  Coating changes fitHardcoat and electroless nickel must be planned into pre-plate dimensions.

GreatLight inspects 100% of parts before shipment. The workflow starts with a raw material check, then in-process monitoring during the run, then a final inspection against the drawing before packing. Reports are available on request, and the accountable engineer signs the final one.

Typical finish targets are Ra 0.8–1.6 μm for most machined surfaces, Ra 0.2–0.8 μm where a sealing face or bearing bore requires it, and Ra 1.6–3.2 μm for as-machined non-critical areas. The tolerance band at the tight end is ±0.005 mm, or ±0.0002 in for drawings in inch units.

Certificates that come with the work include ISO 9001:2015, IATF 16949:2016, ISO 13485:2016 and ISO 27001:2022. The first two cover general and automotive quality systems, the third covers medical device work, and the fourth covers information security around your drawings and files.

Uploads are treated as confidential and an NDA is available on request. If your project is under an existing NDA with a customer, tell the owner at RFQ so the drawing package and inspection records stay under the same terms.

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  Raw material checkCertificates and grade verified before the first cut.
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  In-process monitoringCritical dimensions checked during the run, not only at the end.
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  Final report on requestSigned by the engineer who owns the job.