Stainless instrument parts are unforgiving: the material work hardens under a dull tool, burrs form on every edge that touches tissue, and a surface finish that looks acceptable under workshop light can fail a cleanliness check. We machine medical instrument bases from 304 and 316L stainless on CNC machining centers with a process built around sharp tooling, controlled heat and a documented finishing route, holding bore accuracy of 0.01mm and surface roughness down to Ra 0.4 before passivation and clean packing.

• Tool life management: inserts are changed on a fixed count rather than on failure, because a worn edge work hardens the next pass and ruins the finish.
• Heat control: flood coolant, moderate surface speed and constant feed keep the cut below the work hardening zone, which is what preserves the 0.01mm bore tolerance through the batch.
• Burr strategy: edges are chamfered as part of the tool path, not left for hand deburring, so no burr is pushed into a bore or a seal seat.
• Passivation after machining: free iron and embedded tool residue are removed, which protects the part against corrosion in cleaning and sterilisation cycles.
• Handling discipline: finished parts move to clean packing in lint-free bags, with gloves, to avoid contamination from the shop floor.

1. Material verification against the mill certificate and drawing specification.
2. Bar or plate sawed with allowance, faced and datum established.
3. Rough machining of the outer form, grip cavity and bores.
4. Stress relief pause where the geometry requires it.
5. Semi-finishing and then finishing of bores, faces and mounting features.
6. 5-axis machining of contoured surfaces, radii and blend features in the same setup.
7. In-process bore and perpendicularity checks before the part leaves the machine.
8. Deburring, ultrasonic cleaning and passivation per ASTM A967.
9. Final inspection, material and process documentation, clean double bag packing.

Surgical instrument bases and handles, dental and orthopaedic instrument components, medical device housings, endoscope and laparoscope accessories, aesthetics and dermatology device structures, laboratory instrument mounts and diagnostic equipment parts. Materials include 304, 316L, 17-4PH stainless, titanium and medical grade aluminum depending on the cleaning and sterilisation cycle.

Every shipment can include a dimensional inspection report, mill certificate 3.1, passivation record, surface roughness data and, when requested, a first article inspection report with a process capability summary. This is the documentation most medical OEMs need for incoming inspection and supplier qualification files.

Dongguan Changxinda Precision Technology Co., Ltd has produced custom machined parts since 2008, exporting 50–60% of output to more than 200 customers in medical equipment, robotics, automotive, aerospace, automation, optics, telecom and instruments. With 4-axis and 5-axis machining centers, turn-mill compound lathes and CNC lathes run in two shifts by roughly 100 employees, we schedule medical programs as repeat capacity rather than one-off jobs. Prototypes are delivered in 7–10 days, production batches in 15–25 days, and any schedule risk is communicated before the committed date instead of after it.