:NOTE
Heat the Joint, Not the Solder
The single most important soldering principle is that you heat the joint itself and let the joint melt the solder. If you melt the solder onto the iron and drip it onto the joint, you get a cold solder joint: grainy, dull, and unreliable. Touch the iron to the joint for 2 to 3 seconds first, then feed solder into the joint from the opposite side. This produces a shiny, smooth cone-shaped joint that bonds properly.


:INFO
Choosing the Right Iron
A temperature-controlled soldering station with a fine chisel tip is the best starting setup. Look for a station with a range of at least 200 to 450 C (390 to 840 F). Set the temperature to 330 to 370 C (625 to 700 F) for most through-hole and lead-free solder work. Cheap unregulated irons overheat unpredictably and make it nearly impossible to learn good technique. A Hakko FX-888D or a Weller WE1010 are the standard entry-level recommendations and last for many years with proper care.


:PATH
Tin the Tip Before Every Session
Before soldering anything, apply a small amount of fresh solder to a clean iron
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:INFO
Tin the Tip Before Every Session
Before soldering anything, apply a small amount of fresh solder to a clean iron tip. This is called tinning. Wipe the tip on a damp brass wool cleaner, apply a thin coat of solder, and wipe again. The tip should look bright and silver. A properly tinned


:PATH
Prepare Your Joints
Insert component leads through the PCB holes so the component body sits flush
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:INFO
Prepare Your Joints
Insert component leads through the PCB holes so the component body sits flush against the board. Bend the lead ends slightly outward at about 45 degrees on the solder side to hold the component in place while you work. Clean the pads and leads with


:PATH
Solder the Joint
Touch the iron tip to the point where the lead meets the pad.
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:INFO
Solder the Joint
Touch the iron tip to the point where the lead meets the pad. Hold it there for 2 seconds. Feed rosin-core solder into the junction, not onto the iron. Use 60/40 tin-lead solder or SAC305 lead-free solder. You need just enough solder to form a small cone


:PATH
Identify and Fix Bad Joints
A cold joint looks dull, grey, or granular rather than shiny.
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:INFO
Identify and Fix Bad Joints
A cold joint looks dull, grey, or granular rather than shiny. Reheat it and let it reflow cleanly. A bridged joint has solder connecting two adjacent pads that should not be connected. Remove it with solder wick: lay the copper braid over the bridge,


:CHECKLIST
Basic Soldering Safety
[ ] Work in a ventilated area or use a fume extractor fan
[ ] Wear safety glasses since solder can spit when it bubbles
[ ] Keep the iron in its stand whenever it is not in your hand
[ ] Wash hands after handling solder, especially lead-based solder
[ ] Never leave a hot iron unattended on the bench

:QUOTE [quotetype:personal]
A clean, shiny solder joint is both structurally sound and visually satisfying. If your joint looks bad, it probably is bad. Trust what you see.