5-Axis CNC Machined Bearing Housing with 0.008mm Bore Roundness and Single Setup Machining for Rotary Table Shaft Support

Send Drawing · NDA Available · Price in 24h — 0.008 mm bore roundness · base and bore in one clamping · 1 piece minimum

This square base bearing housing supports a rotating shaft on a rotary table, indexer or inspection platform. The bore is the functional centre of the part: if it is out of round, the bearing outer ring takes an oval preload and the shaft runs with a once-per-revolution vibration that no amount of balancing will remove. We machine the bore, the mounting base and the bolt pattern in one five-axis setup, so roundness stays at 0.008 mm and the base sits square to the bore within 0.01 mm per 100 mm.

The housing is cut from 6061-T6, 7075-T6 or 6082-T6 aluminum plate. The bore is finished with a boring head rather than an interpolated end mill, which avoids the lobing that interpolation leaves in a deep bore, and it is measured with a roundness tester and bore gauge before the batch is released.

1. Drawing review and DFM. We check bore depth to diameter ratio, bearing fit class, bolt access, wall thickness and datum strategy, then return a marked drawing and quotation within one working day.
2. Material verification. Aluminum plate is checked against the mill certificate for grade and temper; 7075 is verified for condition before machining.
3. Sawing and stress relief. Blanks are cut oversize and stress relieved so the bore does not close after the base pocket is machined.
4. Facing and base machining. The base is faced and the mounting pocket cut first, establishing the datum that every later feature is measured from.
5. Five-axis machining in one setup. The bore, side faces, corner holes and counterbores are machined without releasing the part, keeping the bore axis and base square.
6. Bore finishing. The bore is semi-finished, then bored with a fine-feed boring head to H6 and Ra 0.4 µm, with a spring pass to remove deflection marks.
7. Deburr and surface treatment. Edges are broken, the part is cleaned, then clear, black or hard anodized with masking on the bore and datum faces.
8. Final inspection and packing. CMM for hole position and squareness, roundness tester for the bore, air gauge for fit, then foam-separated packing with a first article report.

An end mill interpolating a 60 mm bore leaves a lobed profile that a two-point bore gauge will not reveal: the diameter measures correctly while the roundness is 0.02 mm or worse. A bearing does not care about the average diameter, it cares about the shape it has to sit in. We use a boring head with a spring pass, check roundness on a dedicated tester, and keep the bore length to diameter ratio inside the range where a boring bar will not deflect. Where the drawing calls for a deep bore, we rough from both ends and finish in one pass from the top.

The housing is built to your drawing: bore diameter and depth, base size, bolt pattern, counterbore depth, wall thickness, material grade, anodizing type and colour. A single unit is a normal order with no tooling charge and no setup fee, and the prototype runs on the same programme and inspection plan as the batch. If a feature would raise cost without improving function, our engineer returns a DFM note with a practical alternative and waits for written approval before cutting metal.

• NDA before files. A mutual non-disclosure agreement is signed before drawings, models or samples are released, covering geometry, volume, end use and customer identity.
• No public reference. Confidential housings are never used as samples, catalogue items, website photos or trade show parts; photos need written release.
• Separated production. Sensitive jobs run in a designated cell with named operators, and programmes and fixtures are stored under a project code.
• Controlled data. Files stay on an access-controlled server, and anodizing partners receive the process specification only, never the assembly drawing.

Dongguan Changxinda Precision Technology Co., Ltd has produced custom machined parts since 2008. The plant operates four-axis and five-axis machining centres, turn-mill combined lathes, CNC lathes and milling machines, with 90 to 102 employees and an ISO 9001:2015 quality system. More than 200 customers are served, 50 to 60 percent of output is exported, and annual sales are between USD 10 million and 20 million. Every custom project has a named engineer, every batch ships with a first article report, and every delivery date is confirmed before the order is accepted.

• Confirmed dates. Prototypes in 3 to 7 working days, batch orders in 12 to 22 working days after drawing approval.
• Repeat orders skip setup. Programmes, fixtures and gauge sets stay on file, so the second order starts in production.
• Reserved capacity. Blanket orders are booked into fixed monthly machine time, keeping the same part arriving in the same week.
• Early warning. If material, anodizing or boring capacity threatens the date, you are told before the date is missed, with a partial shipment option.
• Dispatch evidence. Production photos, inspection report and packing list before shipment, tracking number on the day of dispatch.

Each housing is bagged with a desiccant sachet, separated by EPE foam so anodized faces and the bore cannot knock against each other, and packed in a five-layer export carton marked with part number, quantity and batch code. Sea freight goes on a fumigation-free plywood pallet with strapping and stretch film; air freight uses a reinforced carton with edge protectors. Neutral packing is available for distributors selling under their own brand.

Send the drawing with bore size, bearing fit and load direction, and we will return a DFM review, a quotation and a confirmed delivery date within one working day.