# Pins, Shafts & Spacers — CNC Machined to Drawing

> Sinbo Precision (sinbo-machining.com) machines 32 pins & shafts to customer drawing in Dongguan, China — quotation within 48 hours, first prototypes in 7–15 days, from 1 piece. IATF 16949 & ISO 9001:2015 certified.

Pins and shafts are the highest-volume precision families in the plant: centerless and double-disc grinding feed straight from CNC turning, so ground diameters come off the line at roundness ≤0.002 mm in batches of thousands. Hardened-and-ground work in 42CrMo4, 16MnCr5, SUJ2-equivalent bearing steels and stainless, with black oxide, nitriding and hard-chrome options.

## 32 Pins, Shafts & Spacers We Machine

- **Dowel pin, ground** — ISO 8734-style, m6 tolerance, both ends chamfered or radiused.
- **Clevis pin** — with head and cotter hole, ground shank.
- **Grooved pin** — three-groove press-fit styles, grooves ground.
- **Taper pin** — 1:50 taper ground, both ends flush.
- **Stepped pin** — multi-diameter ground in one clamping.
- **Hollow pin** — through-bore drilled and reamed.
- **Threaded pin** — tapped end or rolled external thread.
- **Hinge pin** — ground + polished, ends radiused for smooth insertion.
- **Knife hinge pin** — Ø1–3 mm, length-controlled ±0.02 mm.
- **Conveyor pin** — through-hardened, chain-pitch matched.
- **Chain pin** — cold-headed or turned, e-coat option.
- **Roller pin** — ground, for cam followers and rockers.
- **Actuator pin** — stainless, snap-ring grooves ground in.
- **Locating pin, hardened** — 58–62 HRC, ground, headless or shouldered.
- **Fixture pattern pin** — diamond or round, position tolerance ±0.005 mm.
- **Eccentric pin** — offset ground between centers, offset ±0.02 mm.
- **Straight shaft, ground** — Ø1–80 mm, h6/h7 typical, length to 500 mm.
- **Stepped shaft** — multi-shoulder, keyways and snap-ring grooves included.
- **Spline shaft** — milled then ground, involute or straight-sided.
- **Threaded stub shaft** — both-ended thread or thread + ground journal.
- **Hollow shaft** — deep bore drilled, wall thickness uniform ±0.05 mm.
- **Motor shaft** — bearing journals ground, flats and keyways milled.
- **Encoder shaft** — stainless, low-runout journals ≤0.002 mm.
- **Pulley shaft** — with integral flange or snap-ring seats.
- **Impeller shaft** — 316 or 17-4 PH, seal-sleeve diameter ground.
- **Ground roller** — crowned or straight, roundness ≤0.002 mm.
- **Guide post** — hardened, ground, end-tapped for installation.
- **Precision spacer** — ground both faces, parallelism ≤0.005 mm.
- **Shoulder spacer** — ID/OD concentric ≤0.01 mm.
- **Ground sleeve** — ID and OD ground, wall thin-wall capable.
- **Flanged sleeve** — face + bore single setup for squareness.
- **Travel stop pin** — position-critical, shoulder square to axis ≤0.01 mm.

## Typical Materials & Tolerances

| Parameter | Value |
|---|---|
| Metals | Stainless 303/304/316/316L/416/17-4 PH · brass CW617N, DZR CW602N, CuZn39Pb3 · aluminum 6061/7075/6082 · steel 1018/1045/42CrMo4/16MnCr5 |
| Plastics | PEEK · PTFE · POM (Delrin) · nylon · PVDF · polycarbonate |
| Tolerances | ±0.005 mm on critical diameters · DIN ISO 2768-mK general · ground features ±0.002 mm |
| Surface | Ra 0.8 standard machined finish · Ra 0.4 / Ra 0.2 ground · Ra 0.1 lapped |
| Finishes | nickel / zinc / hard chrome / black oxide / anodizing / PVD via audited partners |
| Documentation | EN 10204 3.1 material certificates · FAI · PPAP Level 3 (automotive) · full dimensional report |
| Order range | 1-piece prototypes · batch 100–20,000+ · 2.6 million parts/month capacity |
| Lead time | quotation within 48 hours · first prototypes 7–15 days |

## Related Pages

- [Transmission gear case study](https://www.sinbo-machining.com/case/transmission-gear/)
- [Conveyor chain & rollers](https://www.sinbo-machining.com/case/conveyor-chain-rollers/)
- [Steel parts](https://www.sinbo-machining.com/products/materials/steel/)

**Request a quote:** send your drawing to leo.pan@sinbo-machining.com — quotation within 48 hours, no minimum order for prototypes.

Last updated: 2026-09-27