7.4.3 Soldering Surface Mount J Lead Components, Hot Gas Method

Outline
This procedure covers the general guidelines for soldering surface mount J lead components. There is basically only one style of J lead component. Whether leads are on two sides or four sides, or whether the component is large or small, the soldering principles are the same.

Minimum Skill Level - Intermediate
Recommended for technicians with skills in basic soldering and component rework, but may be inexperienced in general repair/rework procedures.

Conformance Level - High
This procedure most closely duplicates the physical characteristics of the original, and most probably complies with all the functional, environmental and serviceability factors.

Acceptability References
IPC-A-610 12.0	Surface Mount Assemblies
Procedure References
1.0	Foreword
2.1	Handling Electronic Assemblies
2.2	Cleaning
2.5	Baking And Preheating
7.1.1	Soldering Basics
7.1.2	Preparation For Soldering And Component Removal
7.1.3	Solder Joint Acceptability Criteria
IPC7711 5.6.3	Solder Paste Method/Hot Air Pencil

Tools and Materials

Cleaner
General purpose cleaner for removing contamination.

Hot Air Tool
Tool and nozzles to deliver precise flow of hot air.

Microscope
Precision microscope with stand and lighting for work and inspection.

Solder Paste

Solder paste for component soldering and rework.

Wipes
Nonabrasive, low-linting wipes for cleanup.

Images and Figures

Surface Mount J Lead Component

Figure 1: Add a small bead of solder paste along the row of pads.

Figure 2: Move the tool back and forth to heat all the solder joints until complete solder melt is observed.

Figure:3A - Dot indicates pin 1;B - Indicates pin 5;C - Indicates direction of pin count.

Procedure

Add a small bead of solder paste along the row of pads. (See Figure 1)
Place the component in position.
Adjust the pressure and temperature output of the hot air tool.
Direct the hot air over the component with the hot air tool tip approximately 2.50 cm (1.00") from the solder joint. This initial heating will pre-dry the solder paste.

Note
Solder paste has a dull flat appearance when dried.
When the solder paste has dried, move the hot air tool tip to approximately 0.50 cm (0.20") above the component. Move the tool back and forth to heat all the solder joints until complete solder melt is observed. (See Figure 2)
Remove the tool. Wait a moment for the solder to solidify.
Clean, if required and inspect.

Procedure for reference only.