1. One by one manual welding of small micro-switch, the advantage is that it can accurately grasp the welding of each component, the disadvantage is too time-consuming and laborious.
2. wave soldering for pins, advantages and low price, save time and effort. Disadvantages: As components become smaller and PCBs become denser, the likelihood of bridging and short-circuiting between solder joints increases.
3. Reflow soldering of the patch, the advantage of this process is that the temperature is easy to control, the welding process can avoid oxidation, manufacturing costs are easier to control. The disadvantage of small micro-switch is that solder collapsing occurs during welding heating, which occurs in both preheating and main heating fields.
When the preheating temperature is in the range of tens to 100, the solvents as one of the components of the solder will reduce the viscosity and flow out. If the flow tends to be strong, the solder particles will be extruded out of the solder zone at the same time. If the solder particles can not be returned to the solder zone during melting, the solder balls will be formed.