Virtual welding, is a false spot. The virtual solder spot on the potentiometer welding foot is on and off, and the resulting fault is sometimes absent, and it is not easy to find and eliminate. The resistance body of the potentiometer on the dial needs to be connected by soldering, which leads to the electrode. The quality of the solder joint will seriously affect the overall quality of the potentiometer, and it must be noted that no virtual welding can be generated. So, how to prevent the dial potentiometer virtual welding.

Method 1, on the right amount of tin

Potentiometer manufacturers according to the size of the required solder spot to determine the amount of tin soldering iron dip, so that the solder enough to cover the soldering toughness, forming a suitable size and smooth solder spot. Solder joint is not much tin, tin is much better, on the contrary, this kind of solder joint virtual welding is more likely, it is possible to deposit solder on top, rather than welding on top. If the amount of tin on the first time is not enough, it can be soldered again, but the tin on the previous time must be melted together before removing the soldering iron; If the amount of tin on a too much, you can take away the amount of soldering tip.

Method 2, the welding temperature should be appropriate

In order to make the temperature appropriate, according to the size of the potentiometer should choose the appropriate power of the electric soldering iron, the selected iron power is a certain, should pay attention to control the heating time.

When the solder from the tip of the soldering iron to be automatically scattered on the solder, heating time is sufficient. At this point, quickly remove the soldering tip, leaving a smooth solder spot. If after removing the soldering iron, the solder is left little or no tin, it means that the heating time is too short, the temperature is not enough or the solder is too dirty; If you remove the soldering iron before the solder flow, it shows that the heating time is too long, the temperature is too high. Potentiometer manufacturers generally soldering tip temperature control in the flux melting fast and no smoke is the best welding temperature.

Method 3, welding time should be appropriate

The proper use of welding time is also an important link in welding technology. If it is printed circuit board welding, generally 2 ~ 3S is appropriate. The welding time is too long, the flux in the solder completely volatilizes, loses the welding function, causes the welding spot surface oxidation, causes the welding spot surface rough, black, not bright, with burr or flow and so on flaw. At the same time, welding time is too long, the temperature is too high, but also easy to destroy the components or printed circuit board copper foil. If the welding time is too short, and can not reach the welding temperature, solder can not fully melt, affect the wetting of the flux, easy to cause virtual welding.

Method 4. Keep the soldering tip clean

Because the electric soldering tip is in a high temperature state for a long time, its surface is easy to oxidize or burn, so that the soldering tip thermal conductivity poor and affect the quality of welding. Therefore, you can use a wet cloth or a wet sponge to wipe the impurities on the soldering iron head. When the temperature is too high, you can temporarily unplug the plug or dip in rosin to cool down.

Method 5. Do not touch the solder joint during solidification

Before the solder joint is completely solidified, even a small vibration will deform the solder joint and cause virtual welding. Therefore, in the soldering tip before the evacuation of the welding parts to be fixed, such as tweezers clamping, or soldering tip after the evacuation of rapid blowing with the mouth, the purpose of these practices is to shorten the time of solidification of the solder joint.