Custom Connector Pins: Machined to Your Exact Drawing
We manufacture precision connector pins, socket contacts, pogo pins, terminal pins, and EV charging pins from your 2D drawings or 3D files — in materials from brass and beryllium copper to stainless steel and titanium, with plating options to match your electrical and environmental requirements.
Connector Pin Types We Produce
If it’s a turned or milled metal pin, contact, or terminal, we can machine it to your drawing. Below are the most common families we work in — but this list is not exhaustive. Send us your print and we’ll confirm feasibility within 24 hours.
Pogo Pins (Spring-Loaded Contacts)
Precision-turned housings and plungers for spring-contact interconnects. Used in test fixtures, battery contacts, charging docks, and board-to-board connections where repeated mating cycles are required.
- Ø0.5–8 mm body
- Brass / BeCu / SS
- Gold flash standard
- Custom tip geometry
Connector Contact Pins (Male / Female)
Precision-turned housings and plungers for spring-contact interconnects. Used in test fixtures, battery contacts, charging docks, and board-to-board connections where repeated mating cycles are required.
- Ø0.6–12 mm
- MIL-spec compatible
- Selective plating
- Crimp / solder tails
Terminal Pins (PCB / Through-Hole / Press-Fit)
Precision turned terminal pins for through-hole PCB assembly, press-fit board connections, and wire-wrap applications. Critical OD and knurl geometry machined to match your board specifications exactly.
- Press-fit knurl
- 0.1–2.54 mm pitch
- Tin / gold plate
- Custom lengths
EV Charging Connector Pins
High-current, high-cycle-life contact pins for new energy vehicle (NEV) charging connectors. Designed to handle thermal expansion, arc erosion, and the mechanical demands of repeated high-force mating.
- High-current rated
- Silver / nickel plate
- Ø4–25 mm
- CCS / CHAdeMO geom
RF / Coaxial Contact Pins
Precision-turned inner contacts and outer conductors for RF connectors. Dimensional accuracy on mating diameters is critical for impedance control — we hold OD to ±0.003 mm on RF contact features.
- ±0.003 mm OD
- Gold inner contact
- SMA / N / BNC geom
- Low-PIM materials
Custom Profile Pins & Contacts
If your pin has a unique geometry — stepped OD, slotted crown tip, internal features, knurled gripping zone, or combined thread and pin body — we machine it. Complex profiles are where Swiss-type machining excels.
- Multi-feature profiles
- Cross-drilling
- Internal bores
- OD threading
Where Our Pins Are Used
Our work goes into systems where electrical continuity, dimensional repeatability, and material traceability are not optional.
Semiconductor & Wafer Test
Probe card contacts, socket contacts, and test fixture pins for wafer-level and package-level IC testing. Extreme positional accuracy required.
Aerospace & Defense
MIL-spec connector contacts, rack-and-panel contacts, and circular connector pins. AS9100D certified manufacturing with full lot traceability.
Automotive (IATF 16949)
HVIL pins, HV connector contacts, signal connector terminals, and EV charging pins for electric vehicle platforms and ADAS systems.
Medical Devices
Implant tool connector pins, diagnostic equipment contacts, and surgical instrument connectors. Material traceability and surface finish are non-negotiable.
Industrial & Robotics
Robot cell power and signal pins, servo drive connector contacts, and encoder interface pins for factory automation and collaborative robot systems.
RF & Telecom
Inner contact pins for SMA, N-type, BNC, and custom RF connectors. Impedance-critical geometries held to ±0.003 mm OD tolerance on mating surfaces.
The Machines That Make Our Pins
Connector pin machining demands the highest level of dimensional consistency. Our CITIZEN Swiss-type platforms are the backbone of our pin production — chosen specifically because the sliding headstock design provides unmatched rigidity for long, slender parts.
Swiss-Type CNC Lathe — A20 Series (15 units)
Bar Ø0.5–25 mm · ±0.005 mm · Live milling, drilling, tapping · 2018–2022
Swiss-Type CNC Lathe — A20 Series (15 units)
Bar Ø0.5–25 mm · ±0.005 mm · Live milling, drilling, tapping · 2018–2022
Swiss-Type CNC Lathe — A20 Series (15 units)
Bar Ø0.5–25 mm · ±0.005 mm · Live milling, drilling, tapping · 2018–2022
Swiss-Type CNC Lathe — A20 Series (15 units)
Bar Ø0.5–25 mm · ±0.005 mm · Live milling, drilling, tapping · 2018–2022
Production Capability Summary
| Min. bar diameter | Ø0.5 mm |
| Max. bar diameter | Ø120 mm |
| Standard tolerance | ±0.005 mm |
| Tight tolerance (OD) | ±0.002 mm |
| Surface roughness | Ra ≤ 0.4 μm as-machined |
| Cross-holes / flats | Yes — live tooling |
| Internal bores | Yes — boring & gun drilling |
| Threading | OD & ID — metric and imperial |
| Knurling / slotting | Yes — in-process |
| Swiss-type machines (total) | 43 units dedicated |
| Prototype quantities | From 50 pcs |
| High-volume runs | Up to millions per month |
Why Swiss-type for connector pins?
The guide bushing in a Swiss sliding headstock machine supports the bar stock immediately behind the cutting tool — regardless of part length. This eliminates deflection that would occur on a conventional lathe when machining long, slender parts (L/D > 3:1), which is exactly the geometry of most connector pins and contacts.
Select the Material for Your Connector Pins
Copper Alloys (Primary Conductor Group)
- Brass (C360 / C260): Most common pin base — good machinability, cost-effective
- Beryllium Copper (C17200): Best spring properties + conductivity — pogo pins, spring contacts
- Phosphor Bronze (C510): Good fatigue life for repeated-flex contacts
- Pure Copper (C101/C110): Maximum conductivity — high-current bus contacts
- Tellurium Copper (C14500): Free-machining copper — precision contacts needing high conductivity
Copper Alloys (Primary Conductor Group)
- 303 Stainless: Free-machining — general precision pins
- 316L Stainless: Medical grade — surgical connector contacts
- 17-4PH Stainless: High strength — aerospace contact pins
- Carbon Steel 1045: For hardenable pin bodies needing wear resistance
Copper Alloys (Primary Conductor Group)
- Titanium Gr.5 (Ti-6Al-4V): Lightweight, corrosion-resistant — implant tool contacts
- Aluminum 6061 / 7075: For lightweight connector bodies and backshells
- Kovar (Fe-Ni-Co): Hermetic seal contacts — matched CTE to glass/ceramic
- Inconel 625: High-temperature environments — on request
Material Selection Help
Not sure which material fits your application? Send us your operating conditions — current rating, mating cycles, temperature range, plating spec — and we’ll recommend the right base material and plating stack before you finalize the drawing.
Plating & Surface Finishing for Connector Pins
We coordinate plating through our certified partner network. All plating is traceable to the machining lot and documented in the shipment package.
Hard Gold
0.76–1.27 μm HG over nickel — high-cycle mating surfaces, aerospace contacts.
Flash Gold
0.1–0.5 μm over nickel — cost-effective, low-cycle applications.
Silver
High conductivity — RF contacts, EV charging pins, bus contacts.
Electroless Nickel
Uniform thickness on complex geometry — base layer under gold.
Selective Plating
Gold only on mating zone — cost reduction on long pins with non-contact body.
Tin / Tin-Lead
PCB terminal pins — solderability and press-fit compatibility.
Passivation
Stainless steel — per ASTM A967 or AMS 2700.
Electropolish
Medical grade — burr-free, Ra ≤ 0.2 μm, oxide layer removal.
Tolerance Reference for Connector Pin Machining
Connector pin performance is determined by geometry. A pin OD that is 5 μm oversized won’t seat. A contact bore that is 3 μm undersized won’t engage. The tolerances below are what we consistently achieve in production — not just in first articles.
All tolerances are verified on Mitutoyo CMM (±0.001 mm accuracy) and optical measurement systems. We provide dimensional reports with every first article and on request for production lots.
mm standard production tolerance
mm achievable on critical OD features
mm CMM measurement accuracy
μm as-machined surface finish
| Feature | Standard Tolerance | Achievable (Special Setup) | Notes |
|---|---|---|---|
| Pin OD (turned diameter) | ±0.005 mm | ±0.002 mm | Verified on Mitutoyo micrometer + CMM |
| Overall length | ±0.05 mm | ±0.01 mm | Per part geometry and material |
| Stepped / shoulder diameter | ±0.005 mm | ±0.003 mm | Held in single setup — no re-chucking error |
| Internal bore (ID) | ±0.008 mm | ±0.005 mm | Boring + reaming available |
| Roundness (cylindricity) | 0.003 mm | 0.001 mm | CMM-verified on request |
| Tip geometry (crown, flat, chisel) | ±0.01 mm | ±0.005 mm | Custom tip profiles in one operation |
| Cross-hole position | ±0.05 mm | ±0.02 mm | Live tooling, no re-fixturing |
| Thread pitch diameter | 6H / 6g class | 4H / 4g class | Metric & imperial, thread milling available |
| Surface finish (as-machined) | Ra ≤ 0.8 μm | Ra ≤ 0.4 μm | Electropolish achieves Ra ≤ 0.2 μm |
How We Verify Every Pin Before It Ships
A connector pin that passes dimensional inspection but fails in the field is not acceptable. Our quality system covers incoming material, in-process gauging, and outgoing inspection — with documented results available on every order.
IATF 16949:2016 — Automotive
Covers all automotive connector pin programs. Includes PPAP (up to Level 3), control plans, FMEA, MSA, and SPC requirements.
AS9100D — Aerospace
Full first article inspection reports, lot traceability, nonconformance controls, and configuration management for aerospace contact programs.
ISO 10012:2003 — Measurement Management
Every gauge on the floor operates under a calibration system with traceable standards. Calibration records available on request.
RoHS / XRF Material Verification
Seiko SII XRF analyzer on site for substance verification. RoHS test certificates available for plated pin shipments.
Inspection Equipment
Equipment | Capacity |
|---|---|
Mitutoyo CMM (3-Coordinate) | ±0.001 mm |
Mitutoyo Micrometer (×30 sets) | ±0.001 mm |
Rational 2D / 2.5D Optical | ±0.001 mm · 4 units |
RKE CCD Auto-Sorter | ±0.002 mm · 6 units |
Mitutoyo Roughness Meter | Ra / Rz measurement |
Mitutoyo Height Gauge | ±0.001 mm |
Seiko SII XRF Analyzer | RoHS substance verification |
AISRY Push-Pull Tester | Contact retention force (50 kg) |
Custom Machined vs. Catalog Pins — When Does It Make Sense?
Off-the-shelf connector pins are cost-optimized for standard geometries. If your application requires a non-standard diameter, length, tip geometry, material grade, or plating spec — catalog parts will compromise your design. Here’s when custom machining wins:
| Consideration | Catalog / Off-the-Shelf Pins | Richconn Custom Machined Pins |
|---|---|---|
| Geometry flexibility | Limited to standard profiles | Any profile you can draw |
| Diameter range | Catalog sizes only | Ø0.5–120 mm, any increment |
| Tolerance | Typically ±0.01–0.05 mm | ±0.005 mm standard, ±0.002 mm achievable |
| Material selection | Vendor's available alloys | BeCu, Kovar, 17-4PH, Ti-6Al-4V, etc. |
| Plating specification | Vendor's standard options | Your plating spec, selective zones |
| Supply chain risk | Discontinuation, lead time uncertainty | Your drawing, your control |
| MOQ flexibility | Often high MOQ for specialty items | From 50 pcs prototype to millions |
| Best for | Standard, commodity applications | Demanding, precision-critical, non-standard requirements |
Common Questions About Custom Connector Pin Machining
A 2D technical drawing in PDF or DXF with full dimensions and GD&T callouts is the minimum requirement. A 3D STEP or IGES file greatly speeds up the DFM review and reduces interpretation risk on complex profiles. If you only have a physical sample pin with no drawing, we can reverse-engineer and produce a drawing — ask us about this service.
We machine all standard pogo pin tip geometries: crown (dome), flat, chisel, spear, serrated crown, cup, and custom profiles. The tip is machined in the same operation as the OD — no secondary operation needed — so positional accuracy between tip and body is held tightly. If you have a non-standard tip geometry, send us the drawing and we'll confirm feasibility.
First article lead time for connector pins is typically 10–25 working days, depending on part complexity, whether special materials need to be sourced, and whether plating is in scope. Simple turned pins in brass or stainless are usually at the 10-day end. Complex BeCu profiles with selective gold plating are at the 20–25 day end. We provide a confirmed date at the quoting stage.
We don't have a fixed minimum order quantity. For first articles and prototypes, quantities of 50–200 pieces are typical. For this range, tooling setup is amortized into the per-piece price, so unit cost will be higher than production pricing. We provide pricing for multiple quantity tiers so you can compare prototype vs. production economics and plan your inventory strategy accordingly.
Yes. Beryllium copper (C17200) is a material we work in regularly — it is the preferred choice for pogo pin plungers, spring contacts, and any application requiring both high conductivity and reliable spring-back. BeCu machining requires proper tooling and handling protocols. Our engineers are experienced with its behavior in Swiss-type machining operations.
Yes. We are IATF 16949:2016 certified and can provide PPAP documentation up to Level 3. This includes dimensional results, material test reports (with certs), process flow, control plan, FMEA, and measurement system analysis. Confirm your required PPAP level at the quoting stage so we can build it into the project timeline.
Yes. Selective plating — gold only on the mating/contact zone of the pin, with electroless nickel or tin on the rest — is a standard cost-reduction approach for long pins where only the tip interfaces electrically. The plating zone boundary is defined in your drawing or can be recommended by our engineers. We coordinate selective plating through our partner plating facility.
Yes — this is a common request. If you have a physical sample of the discontinued pin, or its original drawing, we can reverse-engineer the geometry and produce a drop-in replacement. We can work from sample parts using our CMM and optical measurement systems to derive the dimensions. Many customers come to us specifically when a catalog pin has been discontinued and they need to secure their supply chain.
Ready to discuss your connector pin requirements?
Send us your drawing and we’ll review it, flag any DFM considerations, and return a detailed quote within 24–48 hours. No commitment needed at the quoting stage.
- Quote within 24–48 hours
- DFM review at no charge
- Ø0.5–120 mm bar range
- IATF 16949 & AS9100D certified
- Plating coordination included
- Prototype to high-volume production