Drone Arm Bracket with Internal Cable Conduit R25 Bend Radius and 0.01mm Exit Alignment for UAV Wire Routing

Phase wires and signal leads fail at the same two places: where they leave the arm and where they turn a corner too tight. This CNC machining parts arm bracket machines a Ø6 internal conduit through the body with a controlled R25 bend, exit alignment to 0.01 mm against the motor pad, and a grommet seat that keeps the bundle off the aluminum edge — routing without tie-wraps and without chafing.

A conduit that is dimensionally right can still destroy a harness. If the bend radius is tight, the conductor work-hardens and the insulation creeps; if the exit does not line up with the motor pad, the bundle is pulled sideways and rubs on an edge that nobody chamfered. Both failures appear months later, far from the machine shop.

This bracket is machined with the conduit and the motor pad from one datum, so the exit lines up within 0.01 mm, and the bend is held at a minimum R25 rather than whatever the drill path allowed. Every edge the cable can touch gets an R1.0 radius and a polished finish, and the grommet seat is masked during anodizing so the rubber fits as modelled.

• Bend that respects the harness — minimum R25 held through the body, not a drilled angle.
• Exit on the motor axis — 0.01 mm alignment, so no side load on the bundle.
• No chafe points — R1.0 and Ra 1.6 on every edge the cable can reach.
• Grommet fit preserved — seat masked through anodizing, Ø10 ±0.02 mm.

1. Harness review — wire count, bundle diameter, connector size and minimum bend radius confirmed before the conduit path is fixed.
2. Material verification — 7075-T6 received by heat number with ultrasonic check and 3.1 certificate.
3. Rough machining — body, conduit blank and connector shelf roughed with 0.6 mm allowance.
4. First stress relief — low-temperature relief before the conduit is opened through the body.
5. Conduit machining — Ø6 conduit interpolated along the R25 path with a ball nose cutter, entry and exit blended to the motor pad datum.
6. Second stress relief — a short cycle before finishing, keeping the conduit straight where it must be.
7. Finishing — grommet seat, connector shelf and anti-chafe radii finished, edges polished to Ra 1.6.
8. Hard anodizing — 25 µm with conduit and grommet seat masked.
9. Verification — conduit alignment, seat concentricity, shelf flatness on CMM, go/no-go pin through the conduit, FAI shipped.

Wire count, connector size, exit direction and mounting interface all differ by airframe, so the conduit path is designed around your harness. Send the harness drawing and connector data sheet and we return a DFM note on conduit path, bend radius, grommet seat and masking within 24 hours.

• Conduit — single Ø6, twin Ø4, or an open channel with a clamp cover.
• Exit — axial, radial, or angled to match the motor connector orientation.
• Strain relief — grommet seat, P-clamp bosses, or a moulded boot land.
• Shielding — isolated insert or coated bore for signal leads near phase wires.
• Sampling — 1 pc with your harness pulled through for a bend and chafe check.

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.

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