First, the operation check before
(1) 3-5 minutes each day before work a soldering iron to the provisions of the outlet plug, check the iron is hot, if found not hot, first check whether the outlet is plugged in, such as plugged in, if not fever, should immediately Administrator reported that iron can not be opened from the free, not to tip his hand in direct contact
(2) has been uneven oxide or hooked tip should be updated: 1, can ensure good heat conduction effects; 2, to ensure the quality of material being welded. If you put a new iron mouth, paint and maintenance should be erased after the heat and immediately add tin maintenance. Soldering Iron cleaning operations in the former implementation, if more than 5 minutes without using soldering iron, take off the power. Dirty sponge to clean the sponge containing metal particles, or sulfur will damage the sponge tip.
(3) Check whether the suction tin sponge and clean water, if no water, add the appropriate amount of water (the sponge is half the thickness according to the normal leakage of water from time to time, the specific operation is: all the wet sponge after humidity , held in the palm, fingers close to nature), a sponge to clean, not clean sponge containing metal particles, or sulfur will damage the sponge tip.
(4) the reliability of grounding the human body and iron, the body is wearing static ring.
Second, the welding electrode
Specific soldering can be divided into five-step procedure, known as the five-step engineering method to obtain good welding quality must be strictly action.
As described above spot welding is one of the keys for good. In actual production, the most vulnerable to a breach of procedure of the approach is not the first tip and welded pieces of contact, but the first contacts with the solder, the molten solder fell on Shangmo preheated welded parts, This is very easy to produce solder joints Weld, and so the tip must be welded pieces of contact for preheating of the welded parts is an important means to prevent cold solder joint.
Third, the welding essentials
(1) Tip is the weldment with the two way contact
Contact Position: Contact tip should also be connected to each other two are soldered parts (such as welding and pad feet), iron generally tilted 45 degrees, should be avoided by only one of the weldment contact. When the two pieces were welded heat capacity gap, the inclination angle iron should be properly adjusted, iron and welding surface tilt angle smaller, so that the larger heat capacity of iron welded parts and the contact area increases, the heat transfer capacity strengthened. Such as welding LCD pull 30 degrees angle, welding microphones, motors, speakers, tilt angle can be 40 degrees. Two pieces were welded in the same time can achieve the same temperature, the heating is considered ideal.
Contact pressure: iron head and welded parts should apply a pressure contact with, heat conduction is proportional to the strength of the applied pressure, but not on the mig welding electrode damage principle.
(2) the supply of welding wire method
The supply wire should have three essentials not only supply the time, location and quantity.
Supply time: in principle, is to solder temperature weldment is immediately sent to the melting temperature solder.
Supply of position: should be in the iron and welded parts, and as close as possible between the pad.
Supply quantity: should look at the welded parts and the size of the pad, the solder after the solder pad than cover the pad diameter of 1 / 3 can.
(3) Welding time and temperature settings
A, the temperature determined by the actual use to solder a tin the most appropriate point of 4 seconds, the maximum not more than 8 seconds, usually observed tip, when the purple when the temperature is set too high.
B, the general line of electronic materials, the actual tip temperature is set to (350 ~ 370 degrees); surface mount materials (SMC) materials, the actual tip temperature is set to (330 ~ 350 degrees)
C, special materials, special set iron temperature. FPC, LCD connectors use silver solder wire, the temperature is generally 290 degrees to 310 degrees.
D, major components welded feet, the temperature not more than 380 degrees, but can increase the iron power.
(4) Welding Precautions
A, observed in all solder joints before soldering (copper) is smooth and oxidation.
B, in the copper welding electrode, to be spotted welding, so as to avoid short circuit caused by bad welding
Fourth, the operation after the inspection:
(1) used iron tip should be the remainder after the tin in the sponge cloth.
(2) Every day after work must be iron pedestal tin, tin slag, dust and other things cleaned up, and then iron on the iron rack.
(3) will clean up a good soldering iron on the table top right corner.