8 operating essentials for electric soldering iron soldering
1. Weldments' surface treatment
Various electronic bits and cables are welded together manually with a soldering iron. The weldments that are typically encountered need to have their surfaces cleaned frequently, unless the electronic components within the "insurance period" are employed under mass production settings. Work to clean the welding surface of rust, oil, dust, and other pollutants that could impact the quality of the weld. In manual operation, mechanical scraping, alcohol and acetone scrubbing, and other straightforward techniques are frequently used.
2. Pre-welding
Pre-soldering, also known as tinning, tinning, tinning, etc., is the process of pre-wetting the lead wires of the components that need to be soldered or the conductive soldering sections with solder. Pre-soldering is an appropriate name because its mechanism and technique are identical to those of traditional soldering: after the metal has diffused to form a bonding layer, the weldment's surface is "plated" with a layer of solder.
Pre-soldering is not a necessary step in the soldering process, although it is nearly so in hand soldering iron welding, particularly for maintenance, troubleshooting, and R&D.
3. Do not use excessive flux
It's important to have the correct amount of flux, but don't think that more is always better. In addition to increasing the workload required to clean up around the solder joints after soldering, excessive rosin also decreases work efficiency by lengthening the heating time (rosin melts, volatilizes, and steals heat), and when the heating time is insufficient, it is simple to mix it with the solder to create the "Slag inclusion" defect.
It is simple for excessive flux to flow to the contacts during the welding of switching elements, which leads to poor contact. The right quantity of soldering flux should be used so that the rosin scent can only moisten the upcoming solder connections and not leak through the printed circuit board to the component surface or the socket hole (such as an IC socket). There is essentially no need to reapply flux to wires employing rosin cores.
4. Maintain the soldering iron's tip.
The soldering iron tip's surface is easily oxidized to form a layer of black impurities, which almost acts as a heat insulation layer and causes the soldering iron tip to lose its heating effect because it is in a high temperature state for a prolonged period of time during soldering and is exposed to heat-decomposed materials like flux. So, you can always rub the contaminants on the soldering iron frame. Another typical technique is to periodically wipe the soldering iron's tip with a damp cloth or sponge.
5. The solder bridge influences heating
It is not possible for us to constantly change the tip of the soldering iron in non-assembly line operations due to the variety of solder junctions' shapes. It is required to create a solder bridge for heat transfer in order to increase the effectiveness of soldering iron tip heating. The term "solder bridge" refers to the retention of a small quantity of solder on the soldering iron as a conduit for heat transfer between the tip and the weldment during heating.
Obviously, the weldment is quickly heated to the welding temperature because molten metal conducts heat more effectively than air. Be careful not to use a solder bridge that retains too much tin.
6. The solder should be used in an appropriate amount.
Excessive solder not only wastes more expensive tin but also lengthens the soldering process and slows down job operations. What's worse is that too much tin can quickly result in unnoticeable short circuits in high-density circuits. However, insufficient solder cannot create a solid bond and weakens the solder junctions. A lack of solder frequently results in the wires coming loose, especially when connecting them to the board.
7. Firm weld parts should be used.
Before the solder hardens, avoid moving or vibrating the weldment. This is especially important when clamping the weldment with tweezers; make sure you wait for the solder to solidify before releasing the tweezers. This is so because the process of solder solidification involves crystallization. The crystallization theory states that when a weldment is moved during the crystallization process, the crystallization conditions are altered, resulting in the formation of coarse crystals and the so-called "cold welding."
The surface has a dull, bean-dregs-like appearance, and the internal structure of the solder joint is loose, making it simple to develop air gaps and cracks, which reduces the solder joint's strength and causes it to have poor electrical conductivity. As a result, the weldment needs to be held still until the solder has had time to set. In real application, the weldment can be fixed using a variety of appropriate techniques or secure clamping mechanisms.
