Soldering

1
Soldering The Tinning Process

• Electronics 1
• CVHS

2
What is Soldering?

• Solid electrical connection
• Mechanically connects metal to metal
• Electronic soldering
• soft soldering
• 350 F

3
Wave Soldering Machine
4
Wave- Intake
5
Successful Soldering

• 1. Correct solder and flux
• 2. Required equipment
• 3. Clean soldering pencil tip
• 4. Safety

6
Solder

• Metal alloy of tin and lead
• Symbol for tin - Sn
• Symbol for lead - Pb
• 63 tin and 37 lead

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Solder 63Sn/37Pb

• No mushy range
• Eutectic alloy
• Lowest melting solder alloy
• 350F - 600F

8
Solder - 60/40

• Use 60/40 in electronics because less expensive
• Standard Wire Gauge - SWG
• SWG .031

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Flux

• Helps solder flow
• Removes oxidation
• Protects copper while solder melts

10
Flux

• Rosin-based is used for electronics
• Acid-based is corrosive
• DO NOT USE IN ELECTRONICS
• Used in stain glass lampshades

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Flux

• Available as a paste
• Available as a liquid
• Solder has a rosin flux core

12
Equipment

• ?Soldering gun
• Instant heat - high watts
• Too hot
• Copper tracks and pads come off board
• Damage components

13
Equipment

• ?Soldering iron (pencil)
• Slower warm-up
• Lower wattage - 25 watts
• Tight spots
• Various tips - conical best

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Clean Tip

• Tip becomes oxidized with heat
• Wipe off oxidation with damp sponge

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Clean Tip

• File away heavy oxidation

16
Clean Tip

• Tin pencil tip
• Prevents oxidation

17
What is tinning?

• Tinning means covering the tracks pads on
  your PCB with solder
• PCB tracks pads are made of copper
• When exposed to air oils on your skin, copper
  oxidizes
• PCB must be tinned in order to prevent corrosion
  ensure a good electrical connection

18
Steps for tinning your PCB

• 1.Clean all tracks
• 2.Apply flux to all tracks
• 3.Heat tracks add solder
• 4.Spread add solder over all tracks

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Safety

• Solder over workbench
• Treat pencil as always hot
• Safety glasses must be worn
• Solder Contains Lead Washing hands is
  recommended

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Safety

• Put pencil in stand

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Review

• 1. The best ratio of solder to use in electronics
  is
• 2. This is because
• 3. We use _______-based flux
• 4. What is the difference between a soldering gun
  pencil?
• 5. Why do we tin our PCBs
• 6. What safety considerations are important to
  remember when soldering?

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Demonstration