# Custom Fasteners & Precision Screws — CNC Machined to Drawing

> Sinbo Precision (sinbo-machining.com) machines 40 custom fasteners 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.

Standard fasteners are a commodity; special fasteners are a drawing conversation. Sinbo makes screws, nuts and inserts to your print — Torx, spline, tri-wing, pin-in-hex security drives, custom head forms — via Swiss turning for micro sizes and 60–180 T cold heading for volume, followed by thread rolling for fatigue strength. Brass, 303/304/316/416 stainless, alloy steels and aluminum, zinc/nickel/black-oxide finished.

## 40 Custom Fasteners & Precision Screws We Machine

- **Shoulder screw** — ground shoulder, ±0.01 mm on shoulder diameter, thread rolled.
- **Set screw, cup point** — alloy steel or 416, hardened 45 HRC option.
- **Set screw, flat / cone / dog point** — point geometry ground after heat treatment.
- **Thumb screw, knurled** — straight or diamond knurl, brass/303/416.
- **Thumb screw, wing** — pressed wings assembled or machined from solid.
- **Captive screw** — with retaining washer or reduced-neck shank.
- **Captive panel screw** — extended washer, spring-retained per print.
- **Micro screw M0.6–M2** — Swiss-turned, slotted or Torx drive, brass/303/416.
- **Precision screw M2–M6** — socket head to ISO 4762 geometry or custom.
- **Special drive screw** — Torx, hexalobular, spline, tri-wing, square sockets milled.
- **Security screw** — pin-in-hex, pin-in-Torx, spanner drives.
- **Cheese head screw** — slotted or socket, full thread or shank per print.
- **Flat head screw** — 82°/100° countersink, flushness controlled.
- **Pan head screw** — cross-recess or hex drive.
- **Hex cap screw** — grade 8.8/10.9/A2-70 equivalents.
- **Hex flange screw** — integrated flange turned before rolling.
- **Double-end stud** — both threads rolled, pitch-diameter matched.
- **Hex standoff, male-female** — aluminum or brass, thread concentric to hex ±0.05 mm.
- **Hex standoff, female-female** — aluminum 6061, both ends tapped.
- **Round standoff** — knurled or plain, brass typical.
- **Brass threaded standoff** — mold-in or solder-in styles.
- **Hex nut, DIN 934 style** — brass/steel/stainless, tapped after facing.
- **Thin jam nut** — half-height, for lock stacking.
- **Acorn nut** — domed brass or steel, closed crown.
- **Wing nut** — cold-formed or machined wings.
- **Knurled nut** — diamond knurl grip, hand-tight service.
- **All-metal locknut** — crimped-collar style, prevailing torque tested.
- **Special nut to drawing** — non-standard wrench flats, Pozi drive inserts, custom tapers.
- **Turned flat washer** — OD/ID/thickness to print, deburred both faces.
- **Precision shim** — ground thickness ±0.005 mm, 300-series stainless or brass.
- **Threaded insert for plastics** — brass, knurled or diamond-roll OD, heat-stake or press-in.
- **Heat-staked brass insert** — knurl patterns for pull-out strength.
- **Press-fit insert** — interference OD ground for uniform installation force.
- **Eye screw / lifting eye** — fully machined ring or welded + faced.
- **Jack screw** — hex socket head + hardened tip.
- **Adjusting screw** — with calibrated flat or scale on request.
- **Locking screw** — nylon-patch or all-metal lock thread options.
- **Hollow screw** — axial through-hole for oil or coolant feed.
- **Vent screw** — with sintered breather insert pocket.
- **Drain screw** — magnetic tip option for sump service.

## 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

- [Special fasteners case study](https://www.sinbo-machining.com/case/special-fasteners/)
- [Japan custom fasteners](https://www.sinbo-machining.com/case/jp-fasteners/)
- [Korea special fasteners](https://www.sinbo-machining.com/case/kr-special-fasteners/)

**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