Document ID: TOS-TOOL-REF-013 Revision: 1.0 Author: ThisOldScot
Section_1: Overview#
In the Highlands Lab, the goal of desoldering is not just to remove a component, but to leave the PCB in a “Factory Fresh” state for its replacement. Improper desoldering is the #1 cause of catastrophic board damage, specifically lifted pads and torn vias.
This manual outlines the logic of heat transfer during extraction and the proper usage of mechanical and chemical desoldering tools.
Section_2: The Desoldering Toolkit#
| Tool | Technique | Application |
|---|---|---|
| Solder Wick (Braid) | Capillary Action | Cleaning flat SMD pads; removing bridges. |
| Manual Pump (SS-02) | Vacuum Suction | Through-hole components (Capacitors, Joysticks). |
| Desoldering Station | Continuous Vacuum | High-volume through-hole work (Cartridge slots). |
| Low-Melt Alloy | Thermal Bridging | Removing multi-pin SMD chips without high heat. |
Section_3: The “Add Before Subtraction” Rule#
The most common mistake is attempting to remove old solder directly.
- The Logic: Vintage solder is often oxidized and has a high melting point.
- The Protocol: Always add a small amount of fresh Leaded Solder and Flux to the joint before attempting to remove it. This “freshens” the alloy, lowering the overall melting point and allowing the vacuum or wick to pull the solder out in one clean motion.
Section_4: Through-Hole Extraction (The Pump)#
- Add fresh solder and flux to the pin.
- Heat the joint until the solder is completely liquid.
- Place the nozzle of the Engineer SS-02 (or similar silicone-tipped pump) directly over the pin, creating a seal against the PCB.
- Trigger the vacuum.
- Verification: The component pin should now be “loose” and move freely within the hole. If it is stuck, do not pull. Repeat the process.
Section_5: SMD Extraction (Wick & Alloy)#
STAGE_5: 01 // Using Solder Wick#
- Never “scrub” the board with the wick; this causes friction that lifts pads.
- Place the wick on the pad, place the iron on the wick, and let the solder “wick up” into the copper braid. Lift the iron and wick together vertically.
STAGE_5: 02 // Low-Melt Alloys (Chip Quik)#
For chips with many pins (e.g., N64 RAM or PS1 BIOS), apply low-melt solder to all pins. This alloy stays liquid for several seconds, allowing you to gently lift the entire chip with tweezers without using a hot air station.
Section_6: Technical Warning#
Safety_Warning
VIA CLEARING CAUTION: If a through-hole via remains blocked with solder after pumping, do not attempt to “drill” it out with a needle or pick. Instead, add more flux, add more fresh solder, and use a piece of solder wick held against one side of the hole while applying heat from the other. This “pull-through” method is much safer for the internal copper plating.
Section_7: Practical Application: Cartridge Slot Replacement#
When replacing a 72-pin connector or a Mega Drive cartridge slot:
- Apply flux to all pins on the underside.
- Use a desoldering station or high-quality pump to clear every pin.
- Verify every pin is “rattling” in its hole.
- If one pin is stuck, the entire slot will be held in place. Forcing it will tear the via. Patience is the primary tool in desoldering.