Manual welding operation the basic steps
1. Clean the surface of the object to be welded, this step is necessary, even if you can not be lazy again in a hurry. With a knife or sandpaper pads polished bright, shiny copper is exposed. Copper oxide surface will hinder the solder alloy with the formation of this step do not get bit, then Weld is inevitable, because there is no solder joints and completely together, this is the most novice pitfalls.
2. tin, solder iron head number, while the number of dip rosin solder to the surface of the iron in the pad surface for a few seconds, the solder suitably added, can be coated with a layer of solder joints.
3. welding, soldering tweezers sandwich the associated elements, iron should not stay too long, otherwise easily damage the electronics. Just welding is completed, the first not so fast release the tweezers, solder, solidified and then release. Preferably clean smooth joints, do not difficult, abietic suitably applied during the welding can be done.
4. When using a long welding time, the tip will accumulate a layer of black oxide, welding will affect, in particular, soon high-power electric iron, iron head solder oxidation at high temperature, the solution is to prepare a sponge pieces, full of water absorption, the tip under some friction to remove the oxide on top. Try to avoid electric iron-dry, temporarily not in use should be de-energized.
The master electric soldering iron soldering temperature and time, to choose the right position of the contact tip and the solder joint, it is possible to obtain a good solder joint. The right hand during the welding operation can be divided into five steps:
⑴ Step a: Preparation welding (FIG. (A))
Wire left hand, right hand soldering, welding enters standby state. Requirements tip kept clean, oxide-free welding slag, and plated with a layer of solder.
⑵ Step two: heating the weldment (FIG. (B))
Tip against the two connection weldment, weldment heating the entire whole period of about 1 to 2 seconds. For soldering components on a printed board, it is to be noted that the two simultaneous contact tip to be welded. For example, (b) of the wire with the terminal, component leads and pads to be uniformly heated at the same time.
⑶ three steps: feeding a wire (FIG. (C))
When the welding surface of the weldment is heated to a certain temperature, the solder iron in contact with the opposite weldments. Note: Do not solder to the soldering iron head!
⑷ Step Four: removing the wire (FIG. (D))
When the wire melting amount, a 45 ° leftward direction immediately removed wire.
⑸ Step Five: iron removed (FIG. (E))
Solder wettable pad and weldment after welding portion, upper right 45 ° direction away soldering, welding ends. Starting from the end of the third step to the fifth step, the time is about 1 to 2 seconds.
Welding points to note:
⑴ to keep the tip clean
⑵ by increasing the contact area to speed up the transfer
⑶ heating rely solder bridge
⑷ iron evacuated with stress
Iron to timely withdrawal, and the angle formed when the direction of the pad relating to evacuation. Shown below is the effect of different iron withdrawal direction of the tin solder.
⑸ before solder solidification can not move
⑹ amount of solder to be moderate
⑺ to moderate amount of flux
⑻ Do not use the tip as a tool for transporting solder
Over the solder joints Appearance:
① shape is substantially conical and the surface is slightly recessed, sloped was diffuse, welding wire as the center, symmetrically expanded into a skirt shape. Weld points often surface projecting outwardly and to be identified.
② the solder, the solder connection sectionally concave natural transition, smooth the junction of the solder and the weldment, the contact angle as small as possible.
③ smooth surface with a metallic luster.
④ no cracks, pinholes, slag.
For the component layout of the board in the tunnel, most people are used to, "six steps" is to chips and other key components centered methods other components must attack. This method is welding side edge planning, disorderly reflected in the orderly and efficient. However, due to lack of experience for beginners, it is not suitable in this way, beginners can first do a preliminary layout of the paper and pencil to the front of the tunnel for board (component side), then you can also trace also planning out to facilitate their welding.
For the tunnel plate welding method, the use of thin wires generally aforementioned fly line is connected to the fly line is connected is not much skill, but as far as possible horizontal and vertical alignment, clean clear (FIG. 5). Now a popular online method is called tin picked up line method, as shown in FIG. 6, the process is good, stable performance, but more waste tin. Pure tin picked up the line more difficult, affected all aspects of tin wire, welding technology and other individuals. If the first pull a thin copper wire, and then drag soldering performed with thin copper wire, it is much simpler. Tunnel plate welding method is very flexible, vary, you can find a way to fit their own.
FIG fly line connecting a common method
图二 锡接走线法
