Custom CNC Pins
Dowel · joint · clevis · fixture pins · Ø1–20 mm · ±0.005 mm
CHX Metal manufactures custom CNC pins to drawing: dowel, taper, clevis, joint and fixture pins from Ø1-20 mm bar on 70 Tsugami Swiss-type lathes, held at ±0.005 mm, with hardening, grinding and plating options. Monthly capacity is 5 million pieces; quotes return in 24 hours.
A pin is the most boring part on the drawing and the one most often resourced at 2 a.m. It is a few millimetres of steel that decides whether an assembly locates, articulates or wears — and when a pin fails, everything around it gets blamed first. This page covers what a pin drawing should say, and what a pin supplier should be able to prove.
Pin families and where each one is used
| Specification | Capability |
|---|---|
| Dowel pins | Precision location in assemblies; typically hardened, ground, ISO m6/h6 fit |
| Taper pins | Self-holding location where repeated disassembly matters |
| Clevis and cotter pins | Articulated joints and linkages; shear-loaded |
| Robot joint pins | Articulation axes for humanoid and industrial robot fingers — a running CHX application |
| Test and fixture pins | Locating pins for jigs, gauges and test fixtures; wear surfaces and chamfers matter |
| Micro pins | Ø1 mm upward — electronics, sensors, medical devices |
What a pin drawing should specify (and usually forgets)
- Fit class, not just diameter — “Ø3 mm pin” is half a specification; m6 or h6 is the other half.
- Chamfer geometry — the lead-in decides whether automated assembly works; bullet-nose and radiused ends are process choices.
- Hardness and case depth where the pin is a wear surface; through-hardening distorts and may require post-grind.
- Plating thickness — a 5 µm deposit on a pin meant for an interference fit changes the fit; pre-plate dimensions must be engineered.
- Wurth of the tip: crowned, pointed or flat — each is a different operation and the drawing should choose.
How we hold tolerance on a pin
Pins run on the Swiss cell from Ø1–20 mm bar: guide-bush supported turning keeps the profile concentric, sub-spindle and live tooling finish chamfers and back features in-cycle, and critical diameters are verified with in-process SPC at ±0.005 mm. Pins that need m6 or better run a grind-after-heat-treat operation with the grind allowance planned in the turning.
Measurement is optical at these sizes, at recorded temperature. Volume inspection samples per the control plan; full inspection is quoted as its own line when the assembly demands it.
Materials, hardening and finishing
- Carbon and alloy steel: the default for dowel and joint pins; through- or case-hardened per drawing.
- 303/316 stainless: corrosion-sensitive assemblies and food/medical adjacent hardware.
- Brass C36000: conductive pins, current-carrying contacts, non-marring fixtures.
- Titanium Gr5: lightweight articulation pins in robotics and medical instruments.
- Finishes: zinc/nickel/tin plating, passivation, black oxide — 3–7 days in-house.
Volume economics on pin families
Pins are the classic volume part: bar-feed automation, in-cycle completion and per-family tooling make unit cost fall steeply with quantity. Mixed pin families can run as one campaign across the cell, which cuts changeovers out of the lead time. There is no MOQ gate — a single fixture pin and a 500,000-piece dowel release run the same process.
We also manufacture the surrounding turned hardware — spacers, bushings and standoffs — so a pin-plus-hardware kit ships from one plant with one inspection record.
Related guides and capabilities
Micro CNC machining · Swiss screw machining · CNC turned parts manufacturer · Robot finger joints · Brass turned parts · CNC machining capabilities
Request a quote
Send drawing (STEP / PDF / DXF) with material, tolerance and annual volume to mc@chxmetal.com. DFM feedback and a price within 24 hours, NDA on request.
Get a CNC quote · Contact CHX Metal · Supplier profile & certificates
Frequently asked questions
Can you match an m6 fit on dowel pins?
Yes — m6 and tighter are achieved with grind-after-heat-treat on hardened pins, with the grind allowance planned in the turning process. The fit class should be on the drawing, not assumed.
What is the smallest pin diameter you make?
Ø1 mm on the Swiss cell, with optical measurement at recorded temperature. Micro pins are one of the highest-volume product families in the plant.
Can you harden and grind pins in-house?
Hardening runs through qualified partners with the process under our control plan; grinding and final inspection are in-house. The quote states which operations are where.
Do you plate pins, and does plating change the fit?
Yes — zinc, nickel, tin and more, 3–7 days. A 5 µm deposit consumes 40% of a ±0.005 mm band, so pre-plate dimensions are engineered into the process.
What is the minimum order and lead time?
One piece, no MOQ gate. Prototypes in 3–7 days, production in 7–15 days, finishing adds 3–7 days. Mixed pin families can run as one campaign.