Capability · CAP-02
Soldering.
JBC + ESD. J-STD-001 OPERATORS.
Sixteen JBC AD-2BC ESD-tied stations on conductive flooring at 10⁶ Ω resistance to ground. Every operator IPC J-STD-001 certified, re-tested every 24 months. Every joint inspected at 10× per IPC-A-610 §5 by a separate FQC operator before MES sign-off.
Class 3
IPC-A-610
Default acceptance
10⁶
ESD Ω/m
Surface resistance
10×
FQC Microscope
Per IPC §5 inspection
350°C
Tip Temperature
JBC AD-2BC closed-loop
J-STD-001
Operator Cert
Re-tested every 24mo
Sn96.5/Ag3
No-Clean Flux
Cu0.5 SAC305 alloy
Polyolefin
Heat-Shrink
Splice insulation
16
Solder Cells
8 ESD benches × 2 shifts
What Soldering Means Here
Hand Soldering,
Microscope-Inspected,
Class 3 Default.
Wire-harness soldering is point-to-point work — splices, terminal cups, backshell pins, sensor pigtails. It can't be automated, so it has to be operator-perfect. XDPI runs 16 JBC AD-2BC closed-loop stations on ESD-tied conductive flooring (10⁶ Ω resistance to ground surface resistance) with operators who are IPC J-STD-001 certified and re-tested every 24 months.
Every joint is inspected at 10× by an FQC operator on a dedicated Olympus SZX10 microscope station — separately from the solderer — against IPC-A-610 §5 Class 3 acceptance. Wetting must exceed 270°, fillet visible both sides, no dewetting, no exposed strands beyond 1× wire diameter. Rework is photographed and logged in MES.
Soldering hands off downstream to 100% Cirris testing and (for sealed splices) to TPE/silicone overmolding. Wave/SMT board-level work is subcontracted to two audited Laguna PCBA shops; we keep wire-side hand solder in-house under our own IPC-A-610 quality plan. Used heavily on custom harnesses and overmolded harnesses.
Six Solder-Cell Dimensions
What Holds The Joint.
JBC AD-2BC ESD Stations
Sixteen JBC AD-2BC closed-loop solder stations with auto-sleep and tip-temp recovery <2 s from idle. Daily tip-temp verification with FLIR thermal calibrator to ±5 °C of setpoint.
SLD-01
J-STD-001 Certified Operators
Every operator IPC J-STD-001 certified before touching production. Re-test every 24 months per §1.4 — pass at 90% or pull off the cell. Training records sit alongside PPAP.
SLD-02
ESD Discipline · 10⁶ Ω resistance to ground
Lines with conductive flooring at 10⁶ Ω resistance to ground, wrist straps daily-tested at <3.5 × 10⁷ Ω, ionizer airflow >100 V decay in 2 s. Audited monthly per ANSI/ESD S20.20.
SLD-03
Sn96.5/Ag3/Cu0.5 No-Clean
Lead-free SAC305 alloy with halogen-free no-clean flux per IPC J-STD-004 ROL0 grade. Solder lot certs filed per BOM.
SLD-04
Heat-Shrink Application
Polyolefin thin-wall and thick-wall insulation selected to match the cable, splice geometry, and customer specification.
SLD-05
10× Microscope FQC
Every solder joint inspected at 10× on Olympus SZX10 microscopes per IPC-A-610 §5 acceptance criteria — wetting, fill, cracks, dewetting all called against Class 3 thresholds.
SLD-06
Technical Specifications
Solder Cell Datasheet.
| Stations | JBC AD-2BC × 16, all ESD-tied |
| Operator Cert | IPC J-STD-001 (re-test 24 mo per §1.4) |
| Acceptance Class | IPC-A-610 Class 3 (default) |
| Solder Alloy | Sn96.5/Ag3/Cu0.5 SAC305 (lead-free); Sn63/Pb37 on request |
| Flux Grade | IPC J-STD-004 ROL0 no-clean rosin |
| Tip Temperature | 350 °C ±5 °C (closed-loop, daily FLIR calibrated) |
| Recovery Time | <2 s from idle to working setpoint |
| ESD Floor Resistance | 10⁶ Ω resistance to ground per ANSI/ESD S20.20 |
| Wrist Strap Verify | Daily, <3.5 × 10⁷ Ω band |
| Heat-Shrink (Std) | Polyolefin 3:1 thin-wall / 6:1 thick-wall |
| Splice Methods | Crimp + heat-shrink (USCAR-21 crimp evaluation), solder + Raychem ES2000 (sealed industrial) |
| Inspection | 10× microscope FQC, IPC-A-610 §5 Class 3 |
| Off-line Reflow / Wave | Subcontracted — 2 audited Laguna SMT shops |
| Solder Lot Traceability | Per-spool barcode, 7-yr retention IATF §7.5.3 |
| Throughput | Typical 35–60 joints/operator-hour, Class 3 inspected |
Solder Process Flow
Six Steps. Two Operators.
Setup
Operator's wrist strap measured <3.5 × 10⁷ Ω, station tip-temp verified to ±5 °C with FLIR thermal probe, solder lot scanned into MES.
Tinning
Stranded conductors pre-tinned with Sn96.5/Ag3/Cu0.5 to prevent wick-back; tin penetration limited to insulation crimp boundary per IPC-A-620 §5.3.
Joint Form
Mechanical bond formed first (lap, hook, butt) then soldered. Joint must be heated by tip, not solder — solder fed from opposite side per J-STD-001 §5.
Heat-Shrink
Polyolefin 3:1 applied with calibrated heat gun (350–400 °C nozzle); axial coverage 1.5× joint length minimum.
Cooldown + FQC
30 s ambient cool, then 10× microscope inspection per IPC-A-610 §5. Wetting >270°, no cracks, no exposed strands beyond 1× wire diameter.
MES Sign-Off
FQC operator (different person from solderer) logs PASS/REWORK in MES. Joint count, defect class, photo on rework. 7-year retention.
Where Solder Joints Ship
Six Solder Application Buckets.
Tier-1 Automotive Splices
Crimp-splice + heat-shrink encapsulation, with crimp evaluation per SAE/USCAR-21 for chassis and dash harness fan-outs.
EV Battery Pack Tabs
Solder + Raychem ES2000 sealed splice on Cu/Al busbar tab terminations under 0.5 mm welded joints.
Medical Devices
Wire and cable assemblies built to customer drawings for medical equipment.
Robotics Sensor Pigtails
Solder-terminated M12 pigtails on Igus chainflex CF77 for cobot end-effector data lines.
Custom Connector Backshells
Solder cup terminations on D-Sub and customer-specified industrial connector assemblies.
Founder Note · Mr. Fei Bo Hu
“A solder joint is the only place on a harness where the part of the BOM that costs nothing — the alloy and the flux — is also the most likely to fail in the field. We staffed the solder room with the most experienced operators on the floor and we make them rotate every two hours so the eyes stay sharp. The 10× microscope station is a separate operator deliberately — never let the person who built the joint also pass it.”
— Mr. Fei Bo Hu · President · Xudong Group · XUDONG Philippines
Solder Engineering FAQ
Six Questions
Buyers Always Ask.
Q.01Why hand soldering instead of automated wave or selective?
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Why hand soldering instead of automated wave or selective?
Q.02Lead-free or leaded — and why does it matter for harness work?
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Lead-free or leaded — and why does it matter for harness work?
Q.03How do you prevent solder wicking up the conductor strands?
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How do you prevent solder wicking up the conductor strands?
Q.04What heat-shrink do you use and how do you choose?
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What heat-shrink do you use and how do you choose?
Q.05How do you catch a cold or insufficient solder joint?
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How do you catch a cold or insufficient solder joint?
Next Step
Audit A Solder Cell Before You Audit Anything Else.
Bring your J-STD-001 trainer. We open the cell, run a sample joint through 10× FQC, and walk the MES barcode end-to-end with you in 90 minutes. Quote returned within 12 hours. NDA on file. No obligation.