But it is impossible for an engineer to weld with a mounter when making a prototype. Usually manual welding is still needed, so let's learn the steps of manual welding!
1. A method for welding the resistor and capacitor of a patch is characterized by comprising the following steps.
Step (1), before welding, coat a layer of rosin water on the backing plate and wait for it to evaporate;
Step (2), soldering the solder pad with a soldering iron, wherein the contact time between the soldering iron and the pad does not exceed1.5s; ;
Step (3), placing the patch resistor and the capacitor on the pad through electrostatic tweezers, and pressing the patch resistor and the capacitor;
Step (4), solder is added, and after the soldering point is melted by the soldering iron, the solder is fully wetted, and the soldering iron is quickly pulled out;
Step (5), clean the solder joint of the chip resistor and the capacitor to remove the welding slag.
2. The volatilization time of step (1) is 5- 10s.
3. In step (2), the contact time between the soldering iron and the pad is1s..
4. Step (3) The electrostatic tweezers can be flat-mouth anti-slip electrostatic tweezers.
5. Step (5) Clean the solder joint by blowing.
Precautions:
1, the temperature of ferroalloy should not be too low or too high, and it is generally best to keep it at 270℃;
2, patch resistance or patch capacitance must be put right;
3, before welding, you can use scrap circuit board for repeated practice.
In fact, the general patch resistors can be welded by hand, and the main points can be mastered with a little practice.