Diamond Knurled Grip Sleeve with 0.01mm Concentricity and Thin Wall 0.8mm Turn-Mill Machining

Diamond knurled grip sleeves sit between a polished shaft and a human hand, or between a rotating knob and a moulded housing. The knurl has to feel sharp enough to grip, blunt enough not to cut, and consistent from the first part to the thousandth. The bore has to spin true, because a sleeve that is 0.03 mm off centre turns a smooth control into a wobbling one.

We turn and knurl these sleeves on turn-mill combined centres, which means the knurl band, the bore, the shoulder, the cross hole or the engraved marking are all produced without re-chucking the part. Thin walls stay round because the part is never released and re-gripped between the operations that define its geometry.

• Pattern freedom: diamond knurl, straight knurl, spiral or interrupted knurl band, half-knurled sleeve with a smooth finger land.
• Wall range: 0.8 mm to 6 mm, with reduced-pressure knurling and a sample section cut for anything under 1.5 mm.
• Fit: slip fit, light press, H7, or a fit defined by your shaft tolerance — we work to your numbers, not to a catalogue.
• Add-on features: shoulder, flange, external thread, internal thread, cross hole, slot for a grub screw, flat for a wrench, laser marking.
• Materials: 303, 304, 316L, 416, 17-4PH, brass, 6061 and 7075 aluminium, plus black oxide or anodised aluminium versions.
• Length: 8 mm to 250 mm; diameter 5 mm to 90 mm.
• Reverse engineering: send a worn or damaged original, we scan it, send the model for approval, then machine.

Grip sleeves usually carry the shape language of a product line, which makes the drawing commercially sensitive. We sign a mutual NDA before the file is opened, in English or Chinese, and your own form is fine. Only the project engineer, the programmer and the cell supervisor can open the file.

The knurling cell is a camera-free area: no photographs, no video, no social posts, and no sample sleeve left on a shelf where a visitor could see it. We do not publish customer parts, logos or program names without written permission, subcontracting requires your written approval, and files plus inspection data are deleted or returned at program close with written confirmation.

Dongguan Changxinda Precision Technology Co., Ltd has been machining custom parts since 2008: 15+ years, 90 to 100 staff, 50–60% of output exported to North America and Europe, more than 200 customers served, turnover in the RMB 10–20 million band.

The floor holds CNC lathes, turn-mill combined centres and 4-axis / 5-axis machining centres under an ISO 9001:2015 system, producing parts for medical equipment, robotics, automotive, aerospace, automation, laser, LED, lithium battery and precision instrument programs. Everything on this page — turning, knurling, milling, finishing, inspection — happens in our own plant, which is why we can promise a date rather than a range.

• Prototype: 3–7 working days, including a knurl sample for approval where the pattern is new.
• Small batch 10–100 pcs: 7–14 working days in a reserved cell slot.
• Repeat orders: run from archived programs and knurl wheels; no re-programming, no re-fixturing.
• Capacity: 10,000 pieces per month across the plant.
• Visibility: a dated progress note with photographs of your actual parts at each stage.
• Shipping: bagged individually, foam-lined export carton, express or air and sea freight per your forwarder.
• Rush: weekly overtime slots reserved for urgent prototype and line-down cases; tell us the required date first.