Automatic soldering machines can boost work efficiency by over 50%, improve soldering precision and cut material waste. Tasks that originally require two workers can now be handled by only one operator, making automatic soldering machines the top choice for soldering operations. Today we will talk about cold solder joints on automatic soldering machines. First, we need to clarify that a cold solder joint refers to insufficient solder at the joint, resulting in poor contact and intermittent circuit breakage. The quality of solder joints greatly impacts the overall quality of finished products, so cold soldering must be strictly avoided. Below we discuss how to control cold solder joints during production and processing.

1. Air blowing to keep the soldering iron tip clean

The soldering tip of a powered automatic soldering machine stays under high temperature for a long time, which easily causes surface oxidation or burnout and degrades heat conductivity, damaging soldering quality. Therefore, our equipment is equipped with an automatic air blowing function to extend the service life of soldering tips.

2. Properly control soldering time, avoid overlong heating

Reasonable control of soldering duration is a key soldering skill. For PCB soldering, 2 to 3 seconds is the ideal time frame. Excessively long soldering will fully evaporate flux inside solder, oxidize the joint surface and cause defects such as dull, black, burr-covered or flowing solder joints without the protection of flux.

3. Do not touch solder joints by hand before they solidify completely

Tiny vibration before full solidification will deform solder joints and lead to cold soldering. It is recommended to fix components with tweezers during soldering or hold parts steady right after air blowing to shorten the solidification period.

As summarized above, the most direct and fundamental way to eliminate cold solder joints is thorough pre-soldering cleaning. Solder paste is not recommended as it contains acidic substances.