Turn-Mill Machined Hex Adapter Sleeve with Internal Shoulder and 0.01mm Hex to Bore Concentricity

This hex adapter sleeve is turned and milled on a turn-mill lathe with live tooling, starting from 6061-T6 hex bar or from round bar when the hex has to be milled. It features a stepped through bore with an internal shoulder, an external thread at one end, a cross-milled slot at the other, and two radial set screw holes.

The internal shoulder sets the inserted shaft's axial position, so its face must be square to the bore within a hundredth of a millimeter. The hex flats must also sit concentric to the bore so that a wrench applied to the outside does not walk the part on the shaft. Typical uses include motor and gearbox adapters, encoder and pulley mounting, valve and cylinder connections, and quick-change tool interfaces.

Performing the hex, thread, bore, and cross features on a single machine removes the stacked error of three separate setups — exactly what an adapter sleeve cannot afford.

The shoulder is faced in the same clamping as the bore, so its squareness does not depend on a second setup. Across-flats is measured with a micrometer at both ends of the hex, because a hex that tapers slightly will still pass a single mid-length check while rocking in the wrench.

Adapter sleeves connect two mechanical interfaces, so both ends are made to match your mating parts.

• Hex across flats from 5mm to 65mm, or square and double-flat versions.
• Bore combinations: straight, stepped, with internal shoulder, tapered, splined, or threaded at one end.
• External threads: metric, UN, BSP, NPT, left-hand, or multi-start.
• Features: cross slots, radial set screw holes, wrench flats, circlip grooves, keyways, cross holes.
• Materials: 6061-T6 and 7075-T6 aluminium, 303 / 316L stainless, brass, 42CrMo4 for high torque.
• Finishing: clear or black anodizing with bore masked, hard anodizing, nickel plating, passivation.
• Prototype from 1 piece, with the same program and soft jaws kept for repeat orders.

Send the shaft and housing interface dimensions with a drawing or STEP model, and our engineering team returns a fit and tolerance note plus a quote, usually within one to two working days.

Dongguan Changxinda Precision Technology Co., Ltd is a custom CNC machining supplier established in 2008 in Dongguan, Guangdong, China. The shop runs turn-mill combined CNC lathes with live tooling, CNC lathes, and 4-axis and 5-axis machining centers with roughly 100 staff, including dedicated CAM programming and quality teams.

More than 200 customers are served in medical equipment, robotics, automotive, aerospace, automation, laser, LED, lithium battery, and precision testing instruments, and 50–60 percent of output is exported. The company is ISO 9001:2015 certified, with annual sales in the USD 10–20 million range and in-house inspection on CMM and optical measurement equipment. Turn-mill parts with hex, threads, and internal shoulders are routine work, sharing the same capability used for robotics and fluid handling components.

• Monthly capacity above 10,000 pieces for sleeves and adapters, with reserved capacity for repeat programmes.
• Typical lead time: 3–7 days for prototypes, 7–14 days for 10–100 pieces, 14–30 days for mass production.
• Programs, soft jaws, thread inserts, and the approved first article are archived against your part number, so repeat lots start without re-setup.
• CMM, thread gauge, and across-flats data ship with every lot, keeping incoming inspection short.
• Rush service and scheduled release shipping available for projects with a fixed line-side date.
• Export packaging: thread protector, individual bag, desiccant, master carton, palletized for LCL or FCL.

Motor-to-gearbox adapters, encoder and pulley mounting sleeves, valve and cylinder connection sleeves, quick-change tool interfaces, robot end-effector adapters, sensor mounting sleeves, and custom non-standard hex adapter sleeves built to customer drawings.

Send the shaft and housing interface dimensions, or a STEP model, and our engineering team will return a fit and tolerance note with a quotation, usually within one to two working days.