DIY beginners often use soldering iron welding circuit improper operation, easy to cause virtual soldering, continuous soldering and other problems, and the solder joint is not beautiful and neat. Some cautions and operation methods for welding are introduced below for reference.
Scraping before welding
It is not easy to eat tin when there is oil stain or rust on the lead of the component to be welded. Even if the solder is pasted, the result is false soldering. Before welding, scrape clean, dip the pins in rosin, rub the pins back and forth with tin-containing soldering iron head until thin soldering tin coating is coated on the pins.
Nowadays, the solderability of most electronic components is very good, so manual soldering does not need tin-flowing treatment (the premise is to use solder wire with flux). For improper storage of components, resulting in oxidation of pins or contamination of components, tin-flowing treatment is needed.
Master Temperature Skills
If the temperature is insufficient, the solder fluidity is poor and solidification temperature is easy; if the temperature is too high, the solder will drip easily and the solder joint will not hang up. (1) If the temperature is suitable, the soldering iron should be used according to the size of the object. (2) To master the heating time, soldering head with solder pressure welding place, solder will be heated. When soldering tin flows automatically from soldering head to solder object, the heating time is up. At this time, quickly remove soldering head, leaving a bright smooth soldering spot. When soldering head is moved, soldering tin can not be retained, it means heating. Short time, insufficient temperature, or too dirty solder joints, solder head before moving down the heating time is too long and the temperature is too high.
Appropriate amount of soldering tin
According to the size of the solder joint, the amount of solder dipped is enough to cover the solder to form a bright and smooth solder joint. One soldering is not enough to be repaired, but the soldering head must be removed after the previous soldering is melted together. Some people surfacing tin like a swallow nest when welding, the result is that a lot of soldering tin is not strong.
Steady and unshakable
The solder must be firmly held and clamped, especially during solder solidification, it should not be shaken. Shaking during solidification is easy to produce false welding, and the solder joints are like tofu residue. To rest your wrist on a support, sit or stand upright.
Use less solder paste
Solder paste is an acid flux. After use, the solder paste should be wiped clean, otherwise the line will be seriously corroded and the solder joint will be detached. Therefore, a small amount or as little as possible without solder paste. When using solder rod without rosin (rosin is a better solder), soldering iron is dipped in solder tin, then spot on rosin, and then weld quickly. Or use 95% alcohol and rosin to make flux, when welding a drop can be. This solution can also be brushed on clean solder joints and printed circuit boards to make the board shiny as before.
Some people buy inferior solder wire in the market. The appearance of solder is dark and glossy. It needs higher temperature to solder successfully. This kind of solder is the easiest to fake soldering.
When the soldering head is attached with residual superheated tin grains, the soldering head is wiped off the sponge of the soldering platform or scraped off the tin grains with a knife.
How to Brighten Solder Point
The soldering process of PCB is considered unimportant by many people. It is easy to pick up ferrochrome and put the molten tin to the place where it needs to be joined, which results in false soldering and poor contact. It is also feared that the soldering joint is not strong enough and soldering iron contacts soldering joints for a long time, resulting in long-term thermal damage of soldered parts or separation of copper foil from the base plate, or Broken copper foil causes circuit breakage. These two situations will make the electronic fabrication unsuccessful, and will waste more time and manpower to inspect every solder joint and component on the circuit board afterwards, so the soldering method is not well done, it can be judged that your chance of successful fabrication equals zero.
Tin is a kind of solder which is easy to melt and aging at low temperature. When the temperature is low, tin is gelatinous and not sticky, which causes false welding between copper foil of circuit board and foot of parts. When the temperature is right and moderate, the tin of the welding tip is semi-circular and has a reflective surface, which is the best time for adhesion, the parts foot and the bottom board circuit are welded quickly. When the temperature is too high, the tin is round, the color of the tin spot surface is dumb and crepe, indicating that the tin has aged, which will lead to the appearance of false solder joints. Therefore, from the shape of tin grains on the soldering head, we can know when welding is the best time and the success rate of production.
Special note:The above article is from summary of Experience from Professional DIY Welding Master