7.5.3 Soldering Surface Mount Gull Wing Components, Hot Gas Method
Outline
This procedure covers the general guidelines for soldering surface mount Gull Wing components. There is basically only one type of Gull Wing 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.
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 Gull Wing 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.
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 tooltip 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.