On a control linkage, the aluminum block usually outlives three or four bushing sets. But if the bushings are pressed directly into bare aluminum pockets, every replacement opens the pocket a little more, and after the second change the press fit is gone and the whole block is scrap.

Here the pockets are machined to H7 with depth and spacing at ±0.01 mm, given a 15° lead-in chamfer so a replacement bushing is not shaved on entry, and hard anodized with the pockets masked so the aluminum wall resists repeated press cycles. The pivot bore is machined square to the pocket axes within 0.01 mm, so a fresh bushing goes back on the same line.

• Pockets that survive replacement — hard anodized walls, masked bores, ±0.01 mm depth.
• Lead-in chamfer — 15°, so the liner is guided in instead of shaved.
• Axes in one line — pivot bore square to the pockets within 0.01 mm.
• Spacing held at ±0.01 mm — the linkage geometry does not drift after a rebuild.

1. Linkage review — bushing type, press interference, replacement procedure and pivot geometry confirmed before machining.
2. Material verification — 7075-T6 received by heat number with ultrasonic check and 3.1 certificate.
3. Rough machining — block, pocket bosses and pivot bore roughed with 0.6 mm allowance.
4. First stress relief — low-temperature relief so pocket spacing stays within tolerance after boring.
5. Semi-finish — pockets and pivot bore semi-finished with light radial engagement.
6. Second stress relief — a second cycle before the pockets are finished to depth.
7. Pocket finishing — four pockets bored to H7 Ø12 at 8.0 mm ±0.01 mm, spacing ±0.01 mm, chamfers cut in the same clamping.
8. Hard anodizing — 25 µm with pockets, pivot bore and mating faces masked.
9. Verification and fitting — CMM on spacing and depth, bushing press trial, replacement cycle check, FAI shipped.

• Bushings — PTFE-lined bronze, plain bronze, or iglidur polymer for dry running.
• Pockets — 2 to 6, in line, staggered, or on two axes with a compound pivot.
• Retention — press fit, retaining compound, or a circlip groove for tool-free replacement.
• Body — solid, ribbed, or truss-lightened to a weight target.
• Sampling — 1 pc pressed, removed and re-pressed to prove the replacement cycle.

Motor geometry, stator stack and winding data are competitive information, so access is limited from the drawing stage onward.

• NDA first — mutual NDA and non-circumvention signed before any file is exchanged.
• Isolated area — dedicated machines and authorized staff, no phones or photography inside.
• Codified routing — internal codes on travelers and labels instead of your part numbers.
• Data control — per-project folders on a permission server, destroyed on request with a record.
• No display — no drawings, part photos or logos in samples, catalogs, the website or social media.

Dongguan Changxinda Precision Technology Co., Ltd. — founded in 2008, 90-102 staff, ISO 9001:2015 certified, annual sales USD 10-20 million, export share 50-60%, serving customers in Europe, North America, Japan and Southeast Asia.

Machining, stress relief, anodizing and metrology run in one plant: 5-axis and 4-axis machining centers, turn-mill centers, surface grinders, wire EDM, CMM, 2.5D vision metrology and automated anodizing lines. About 12,000 aluminum parts ship each month, most of them small precision parts where the fixture and the boring sequence decide the result.

1. 01 Consumer Electronics — Phone, tablet and laptop housings · heat sinks · camera brackets · VR/AR headset structural parts · smart wearable housings
2. 02 Automation & Industrial Equipment — Automation jigs · fixtures · module frames · transmission sliders · motor mounts · sensor housings · conveyor line components
3. 03 Semiconductor & Vacuum Equipment — Vacuum chambers · vacuum fittings · semiconductor equipment precision bases · thermal insulation parts · inspection fixtures
4. 04 Medical Devices — Surgical instrument bases · medical device housings · endoscope components · aesthetic equipment structural parts (medical grade aluminum / stainless steel)
5. 05 Automotive — EV motor housings · battery end plates · sensor brackets · lamp structural parts · aftermarket parts · hydraulic valve blocks
6. 06 Aerospace & UAV — Aircraft structural parts · UAV frames · landing gear components · avionics instrument housings (lightweight precision parts)
7. 07 Optics & Photonics — Optical lens barrels · lens mounts · light source heat sinks · camera module brackets · inspection optical stages
8. 08 Telecommunications — 5G heat sink cavities · filter housings · signal adapter brackets · telecom equipment enclosures
9. 09 Robotics — Robotic arm joint parts · robot bases · reducer housings · AGV chassis structural parts
10. 10 Instruments & Meters — Inspection equipment housings · precision gauge bases · flow meter parts · laboratory equipment components

Two shifts 07:30-22:00, six days a week, with weekend shifts in peak season. Capacity is locked weekly for volume programs, so a rush order never displaces a scheduled batch.

• Samples — 7-10 days, checked on your stator or bearing set before the batch is released.
• Batch — 15-20 days from deposit and drawing approval.
• Buffer stock — semi-finished stock for repeat models, cutting repeat lead time by about 30%.
• Shipping — DHL/FedEx/UPS in 3-5 days for samples; air or sea for volume; EXW Dongguan, FOB Shenzhen or CIF.
• Documents — FAI, 3.1 material certificate, CMM report and packing list with every shipment.

Send STEP / IGES / DWG / PDF and receive DFM feedback plus a formal quotation within 24 hours.

Dongguan Changxinda Precision Technology Co., Ltd. · ISO 9001:2015 · Dongguan, Guangdong, China