6061-T6 Aluminum Split Clamp Bracket Cylindrical Mounting Bracket with 0.01mm Bore Axis Squareness and Controlled Clamp Gap

This split clamp bracket delivers 0.01 mm bore-axis-to-base squareness, a controlled clamp gap, and a bore that is measured after slitting — so the fit you specify is the fit you get on the line.

This bracket clamps a cylindrical shaft, a reducer output, or a sensor tube to a robot arm and locks it by closing a slit with a pinch bolt. It functions as an adjustable joint, so the bore must be a close sliding fit before clamping — and it must stay round after clamping.

Two numbers decide whether that works: how square the bore axis is to the mounting pad, and how much the bore distorts when the slit is cut and the bolt is tightened.

We machine the base pad and the bore in one five-axis setup so the axis is square to the pad within 0.01 mm, then cut the slit, then measure the bore again. The clamp gap is machined to a controlled width so the bolt can close the collar without crushing the shaft.

1. Drawing and clamp review. We confirm bore size and fit, wall thickness, slit position, clamp gap, bolt size and mounting pattern, and check that the collar still has material to close — then quote within one working day.
2. Material verification. 6061-T6 stock is checked for grade and temper. Where the bracket carries a heavy arm load, we confirm the section is adequate for the requested wall.
3. Stress relief and datuming. The blank is stress relieved and faced, establishing the pad as the datum for the bore axis.
4. Bore and pad in one setup. The bore is bored and the base pad faced in the same five-axis clamping — the only way to hold 0.01 mm squareness between them.
5. Mounting holes. Counterbored mounting holes are drilled and dowel positions, where specified, are reamed in the same setup so the bracket locates on the arm without adjustment.
6. Slitting. The clamp slit is cut with a slitting saw to a controlled gap. Cutting the slit before the bore is finished would let the collar spring and the bore would finish oval.
7. Pinch bolt hole and deburr. The cross hole is drilled and tapped, and the slit edges and bore entry are deburred by hand — because a burr at the slit is a burr inside the clamp.
8. Anodizing and inspection. Anodizing with the bore and pad masked, then CMM for squareness, bore gauge for size and roundness after slitting, and a first article report with the batch.

A collar that is round before the slit is not necessarily round after it. Cutting the slit releases the hoop stress left by boring, and the two halves spring apart or in depending on how the residual stress sits in the material. If the bore is finished before slitting and measured only afterwards on a sample that is left open, the number in the report describes a part the customer never uses.

So the sequence is deliberate: rough the bore, cut the slit, finish the bore, then measure with the bolt tightened to the specified torque. That last condition matters. A collar measured open and used clamped can move 0.02 mm — enough to turn a sliding fit into a press fit and make the joint impossible to adjust on the line.

Bore diameter, collar length, slit orientation, clamp gap, bolt size, pad size, dowel pattern and coating are all built to your drawing. One piece is a normal order with no tooling charge and no setup fee, and the prototype is inspected under the same clamped condition as a batch. If the wall is too thin for the clamp force you specified, our engineer says so before machining.

• NDA before files. Mutual non-disclosure is signed before drawings or samples are released, covering geometry, volume, end use and customer identity.
• No public reference. Confidential brackets never appear as samples, catalogue items, website photos or trade fair parts.
• Separated cell. Sensitive work runs with named operators and project-coded programmes.
• Partner control. Anodizing suppliers receive process specifications only, never the assembly drawing.

Dongguan Changxinda Precision Technology Co., Ltd has machined custom parts since 2008. The plant runs four-axis and five-axis machining centres, turn-mill lathes, CNC lathes and milling machines, employs 90 to 102 people under ISO 9001:2015, serves more than 200 customers, exports 50 to 60 percent of output and records annual sales of USD 10 to 20 million.

• Dates in writing. Prototypes 4 to 7 working days, batch orders 12 to 20 working days after drawing approval.
• Repeat orders skip setup. Programmes, fixtures, slit gauges and torque settings stay on file.
• Reserved slots. Blanket orders are booked into fixed monthly machine time.
• Early notice. If material, anodizing or capacity threatens the date, you are told before the date is missed.
• Dispatch evidence. Photos, inspection report and packing list before shipment.

• ✓Consumer Electronics: phone, tablet and 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, conveyor line parts
• ✓Semiconductor & Vacuum Equipment: vacuum chambers, vacuum fittings, precision equipment bases, thermal isolation and insulation parts, inspection fixtures
• ✓Medical Devices: surgical instrument bases, diagnostic instrument housings, endoscope components, aesthetic device structural parts (medical-grade aluminum and stainless steel)
• ✓Automotive: new energy motor housings, battery end plates, sensor brackets, lamp structural parts, tuning parts, hydraulic valve blocks
• ✓Aerospace & UAV: aircraft structural parts, drone frames, landing gear parts, avionics instrument housings (lightweight precision parts)
• ✓Optics & Photonics: optical lens barrels, lens mounts, light source heat sinks, camera module brackets, inspection optical benches
• ✓Communications: 5G heat dissipation cavities, filter parts, signal adapter structural parts, telecom equipment housings
• ✓Robotics: robot arm joint parts, robot bases, reducer housings, AGV structural parts
• ✓Instrumentation: test equipment housings, precision gauge bases, flow meter parts, laboratory equipment accessories

Each bracket is bagged with desiccant, seated in a foam tray so the bore and slit edges cannot be bruised, and packed in a five-layer export carton marked with part number, quantity and batch code. Sea freight ships on fumigation-free plywood pallets; neutral cartons are available.