Watch the video about different types of solder and learn the terminology
Exercise 2
Learn more about the tools you need
Soldering iron
For electronics work the best type is one powered by mains electricity (230V in the UK), it should have a heatproof cable for safety. The iron's power rating should be 15 to 25W and it should be fitted with a small bit of 2 to 3mm diameter. Low voltage soldering irons are available, but their extra safety is undermined if you have a mains lead to their power supply! Temperature controlled irons are excellent for frequent use, but not worth the extraexpense if you are a beginner. Gas-powered irons are designed for use where no mains supply is available and are not suitable for everyday use. Pistol shaped solder guns are far too powerful and cumbersome for normal electronics use.
Soldering iron stand
You must have a safe place to put the iron when you are not holding it. The stand should include a sponge which can be dampened for cleaning the tip of the iron.
Desoldering pump (solder sucker)
A desoldering pump, colloquially known as a solder sucker, is a device which is used to remove solder from a printed circuit board. There are two types: the plunger style and bulb style. The plunger style is usually a small, spring-loaded device that sucks the solder off the soldered connection. It is applied to a heated solder connection, then the user activates the device (usually via button) to suck the solder away. Other models use a powered vacuum pump instead of spring to generate the vacuum. These pumps are less likely to damage fragile surface-mount components because they have a constant air flow, instead of the sudden, strong air flow of a spring-loaded type. The bulb style works much like the plunger style, except a bulb is used to create the vacuum. A desoldering iron is a soldering iron with a desoldering bulb attached to it.
Exercise 3
Watch the video and learn how to use solder wick
Exercise 4
Read this text and learn the words in bold
Requirements on soldered installations
Components
Components (e.g., electronic devices, mechanical parts, printed boards) selected for assembly shall be compatible with all materials and processes, e.g., temperature ratings, used to manufacture the assembly/product. Moisture sensitive components shall be handled in a manner consistent with documented procedures.
Electrostatic Discharge (ESD)
If any ESDsusceptible devices are employed, the manufacturershallestablish andimplement a documented ESD control programin accordance with the agreed standards or as otherwise specified. Documentation necessary for an effective programshallbe available for review.
Facilities
Cleanliness and ambient environments in all work areas shallbe maintained at levels that prevent contamination or deterioration of soldering tools, materials, and surfaces to be soldered. Eating, drinking, and/or use of tobacco products shall be prohibited in the work area.
Environmental Controls
The soldering facility should be enclosed, temperature and humidity controlled, and maintained at a positive pressure.
Temperature and Humidity
When humidity decreases to a level of 30% or lower, the manufacturer shall verify that electrostatic discharge control is adequate, and that the range of humidity in the assembly area is sufficient to allow soldering and assembly materials to function correctly in the process, based on vendor recommendations or documented evidence of process performance.
For operator comfort and solderability maintenance, the temperature should be maintained between 18°C [64.4°F] and 30°C [86°F] and the relative humidity should not exceed 70%.For process control, more restrictive temperature and humidity limits may be required.
Lighting
Illumination at the surface of workstations should be 1000 lm/m2 minimum. Light sources should be selected to prevent shadows.
Soldering Requirements
Solder connections or terminations on components designed for surface mounting shall exhibit conditions that meet the general descriptions, and shall not exhibit any of the defect conditions.
Visual Inspection
The assemblyshallbe evaluated in accordance with the established process control plan or by 100% visual inspection.
Exercise 5
Read the safety precautions and translate them into Estonian
Never touch the element or tip of the soldering iron.
They are very hot (about 400°C) and will give you a nasty burn.
Take great care to avoid touching the mains flex with the tip of the iron.
The iron should have a heatproof flex for extra protection. An ordinary plastic flex will melt immediately if touched by a hot iron and there is a serious risk of burns and electric shock.
Always return the soldering iron to its stand when not in use.
Never put it down on your workbench, even for a moment!
Work in a well-ventilated area.
The smoke formed as you melt solder is mostly from the flux and quite irritating. Avoid breathing it by keeping you head to the side of, not above, your work.
Read the text about terminology you need and translate it into Estonian
In science, the use of the word fluid applies to both liquids and gases. A fluid is a substance that does not have a fixed shape and whose moloecular constituents move freely past another. Thus, fluids take on the shape of their containers. The distinguishing feature between a liquid and a gas is that a liquid is a fluid that has a relatively fixed volume, and a gas is a fluid that does not have a fixed volume: gases can be compressed and can expand to fill a container entirely.
When a liquid or solid substance changes to a gas or vapour, it is known as vaporisation. There is fundamentally no difference between the terms gas and vapour, but gas is the more high-frequency term and is used to describe a substance that appears in the gaseous state under standard conditions of pressure and temperature. The term vapour is generally used to describe the gaseous state of a substance that normally appears as a liquid or solid.
Condensation is the change in matter of a substance to a denser phase, such as a gas ( or vapour) to a liquid. Condensation occurs when a vapour is cooled to a liquid, or if it is compressed. (i.e, the pressure on it is increased) into a liquid, or undergoes a combination of cooling and compression. Liquid which has been condensed from a vapour is called condensate. A device or unit used to condense vapours into liquid is called a condenser. The water seen on the outside of a cold glasson a hot day is condensation.
Moisture generally refers to the presence of water, often in trace amounts. Humidity is more specific, and refers to the amount of water, often vapour in the air. It is measured in three ways: absolute humidity, relative humidity and specific humidity. Relative humidity is the most frequently encountered measurement of humidity because it is regularly used in weather forecasts, as it indicates the likelihood of precipitation, dew, or fog. Higher relative humidity also makes it feel hotter outside in the summer because it reduces the effectiveness of sweating to cool the body by preventing the evaporation of perspiration from the skin. This effect is calculated in a heat index table. Warmer air has more thermal energy than cooler air; thus, more water molecules can evaporate and stay in the air in a vapour state rather than a liquid state. This may be why people say that warmer air "holds" more moisture - in warmer air, there is more energy for more water molecules to hold themselves in the air.
