04. Through-Hole & Mixed Technology
Where SMT ends and hands-on craft begins: soldering, rework, coating, and reliability engineering.
Part 1. Automated THT: Selective & Wave (setup, profiling, defects)
THT provides the mechanical reliability anchor on mixed boards, relying heavily on chemistry and ...
3.1 THT-Friendly Design
Through-Hole Technology (THT) remains mandatory for mechanical stability (connectors, relays), hi...
3.2 Fluxing & Preheat Control
The perfect solder joint begins with chemistry and heat. Through-hole soldering is a high-risk th...
3.3 Selective Solder Programming
Selective soldering is the high-precision solution for mixed-technology boards, solving the probl...
3.4 Wave Solder Setup
Wave soldering is the original mass production technique, and its effectiveness is determined by ...
3.5 Common Defects & Corrections
Solder balls, non-fills, and bridging are often not defects of the solder wave itself, but failur...
Part 2. Manual THT & Rework (tools, techniques, defect atlas)
Manual soldering and rework are the final human element, demanding professional skill to ensure e...
3.6 Hand Soldering Foundations
Hand soldering remains essential for rework, repair, and specialized low-volume assembly, managin...
3.7 Fluxes, Alloys and Aids
Hand soldering is a controlled process, but its chemical core relies on the quality and purity of...
3.8 Rework Flow Control
Reworking complex surface mount devices (SMD), such as BGAs and QFNs, is one of the most delicate...
3.9 Defect Atlas & Acceptance
Defect evaluation sits at the intersection of quality, speed, and fairness in electronics manufac...
3.10 Data Logging & Repair Tickets (THT/Mixed)
The manual and mixed-technology assembly process — especially THT insertion, wave soldering, and ...
4.4 Rework & Repair
A dedicated section on "The Art of Undoing." How to replace a BGA (Ball Grid Array) using hot air...
Part 3. Cleaning, Depanelization, Press-Fit, Conformal Coating/Potting
Your product's long-term lifespan is decided after soldering. This chapter shows how to achieve t...
3.11 Clean vs No-Clean Decisions
Residues left behind in assembly are often invisible, yet they can dictate whether a circuit surv...
3.12 Cleaning Methods & Fixtures
Residues left behind in assembly are often invisible, yet they can dictate whether a circuit surv...
3.13 Depanelization Choices
Depanelization is the final mechanical process that separates individual Printed Circuit Boards (...
3.14 Press-Fit Technology
Press-fit is a mechanical interconnection technology that uses a compliant pin design to create a...
3.15 Coating & Potting
Residues left behind in assembly are often invisible, yet they can dictate whether a circuit surv...