Multi-Step Bore Turn-Mill Composite Flange Connector Housing with 0.01mm Tolerance

• Bore Fit 0.01 mm
• Step Diameters Held to fit class
• Process Turn-Mill
• Bore Datum All steps from one datum
• Min Order 1 Piece
• Prototype No tooling charge

• ISO 9001:2015
• 6061-T6 / 7075 Aluminum
• CMM First-Article Report
• NDA on Request
• Exporting Since 2008

This square flange connector housing with a multi-step bore is turn-mill machined by Dongguan Changxinda Precision Technology Co., Ltd., a CNC factory established in 2008. Each bore step is machined to its own fit class and depth, and the steps are bored from one datum so they stay concentric with each other and square to the flange face. Critical features — step diameters, fit clearance, step depths and bore concentricity — are held to ± 0.01 mm and verified on a CMM.

A multi-step bore is a chain of fits. A shaft, a seal and a bushing each seat at a different step, so every diameter has to land inside its own tolerance band, and all of them have to share one axis. If a step is bored from a fresh setup, the axis shifts and the parts that should slide in bind instead. Boring every step from the same datum keeps the chain aligned, and checking with plug gauges plus CMM confirms the fit before the parts leave the shop.

Each multi-step bore housing follows a controlled eight-stage route:

1. Drawing review & DFM: STEP / IGES / SolidWorks / 2D PDF checked for step diameters, fit classes, depths, slots and sealing faces.
2. Material: 6061-T6 / 7075 aluminum with mill certificates.
3. Turn-mill programming: CAM toolpaths sequenced step by step from a single bore datum.
4. Rough boring all steps: each diameter roughed with uniform stock, chips cleared between steps.
5. Semi-finish: stock equalised so the finishing pass cuts evenly across each step.
6. Finish bore to fit class: each step finished to its tolerance band, with plug-gauge checks during the run.
7. Slots, flange & surface treatment: locating slots milled, square flange finished, then anodizing or per drawing.
8. CMM inspection: step diameters, fit clearance, depths and concentricity recorded on a first-article report.

The multi-step bore housing is a starting point. We machine custom versions with your own step count, diameters, fit classes, depths, locating slots and flange size — all to drawing.

We sign an NDA before engineering review, restrict drawings to the assigned programming and machining team, and never display or reuse customer geometry. Fixtures and programs built for your part stay dedicated to your program, and surplus or reject parts are scrapped on request.

Changxinda runs a plant established in 2008 with 90+ staff, multiple turn-mill lathes and 4-axis / 5-axis machining centers backed by a dedicated QC lab.

One shop, ten industries, one inspection standard:

• Consumer Electronics Phone / tablet / laptop housings, heat sinks, camera brackets, VR/AR headset structural parts, smart wearable shells.
• Automation & Industrial Equipment Automation fixtures, jigs, module frames, transmission sliders, motor mounts, sensor housings, assembly line components.
• Semiconductor & Vacuum Equipment Vacuum chambers, vacuum fittings, precision bases for semiconductor equipment, thermal and insulating parts, inspection tooling.
• Medical Equipment Surgical instrument bases, medical testing instrument housings, endoscope accessories, medical aesthetic device structural parts (medical-grade aluminum / stainless steel).
• Automotive New-energy motor housings, battery end plates, sensor brackets, headlamp structural parts, modified parts, hydraulic valve blocks.
• Aerospace & UAV Aircraft structural parts, drone frames, landing gear accessories, aviation instrument housings (lightweight precision parts).
• Optics & Photonics Optical lens barrels, lens mounts and bases, light source heat sinks, camera module brackets, inspection optical platforms.
• Communications 5G heat dissipation cavities, filter parts, signal adapter structural parts, communication equipment housings.
• Robotics Robotic arm joint parts, robot bases, reducer housings, AGV structural parts.
• Instruments & Meters Testing equipment housings, precision gauge bases, flow meter parts, laboratory equipment accessories.

• Multi-step bore with each step cut to its own fit class
• ±0.01 mm on step diameters, depths and concentricity
• All bore steps machined from a single datum
• Locating slots milled relative to the bore axis
• Square flange finished square to the bore
• 6061-T6 / 7075 aluminum with mill certificates
• Plug-gauge checks during production, CMM at final
• NDA and IP protection on request
• Anodizing, polishing and custom surface finishes
• From 1-piece prototypes to scheduled production

• Q1: How do you hold several bore steps to different fits?

  Each step is finished to its own tolerance band from a single datum, with plug-gauge checks during the run and CMM verification at final inspection.

• Q2: What keeps the bore steps concentric with each other?

  All steps are bored in one setup without re-chucking, so there is no axis shift between steps. Concentricity is then confirmed on the CMM.

• Q3: Can I specify custom fit classes?

  Yes — H7, H8, g6 or any fit on your drawing. Step count, diameters, depths and locating slots can all be machined to specification.

• Q4: Do you check fit before shipping?

  Yes. Plug gauges are used during production for each step, and the CMM report records the final diameters and concentricity.

• Q5: Will you sign an NDA?

  Yes, before engineering review. Drawings are limited to the assigned programming and machining team and never reused or displayed.

• Q6: What is the lead time?

  Prototypes 3–7 days, small batches 7–14 days, mass production 14–30 days depending on complexity, with rush support available.