surface mount tech

Soldering Dictionary

Surface mount technology- Surface mount technology allows soldering of components directly onto the surface of the PCB without the need to pass leads through the board. Surface-mounted components are becoming more and more common due to the obvious shortcomings associated with the use of through-hole soldering. However, the technique is a bit less straightforward as compared to the through-hole technique.

Soldering tip- A tip is the sharp end of a soldering iron that delivers heat onto the workspace. Tips usually vary in size, shape, and in some case the material. There are three main tip shapes, bevel, conical and chisel shapes.

Soldering tinner- This is one of several tip cleaning alternatives. The working of a tip tinner is relatively simple. Once an iron tip is coated with unwanted material, mostly solder from operations, it is dipped into the tinner at the temperature normally attained during soldering. Due to its reducing characteristics, the tinner will stick to the tip of the iron thus forming a bright and shiny surface and removing all other unwanted material. Tinners, unlike a wide range of other soldering pastes are almost hazard-free.

Solder flux- Soldering flux is an agent that can serve various purposes such as cleaning, purifying, dissolving metal oxides and acting as a reducing agent that undoes the effects of oxidization. Basically, at room temperatures, most kinds of flux are inert. This however changes once the flux is exposed to high temperature levels.

Solder fumes- These are ingestible fumes produced in soldering due to the presence of various compounds. These include lead and resin fumes mostly. When rosin is heated, it generates a wide range of fumes, most of which cause discomfort, allergies and in situations of high exposure causes respiratory problems. Continued exposure to these fumes causes long-term respiratory problems that are very difficult if not impossible to reverse.

through-hole soldering

A-Z of soldering Dictionary

Silver- Silver is a soft, whitish metal that has the best electrical and thermal conductivity and also the best reflectivity among metals. These characteristics have made silver ideal for a variety of uses over a wide range of industries. In soldering, silver is used as an alloy with other metals to form solder that portrays among the highest liquidus of any solder. Silver, in its pure form has a melting point of about 1,863 degrees Fahrenheit. This makes it generally unsuitable for low-temperature soldering activities.

Through-hole soldering- Through-hole soldering is one of the more popular electronic component mounting schemes used in a wide range of printed circuit boards. The components to be mounted have leads running from both ends. These leads then pass through holes within the circuit boards onto which they are fixed then soldered using any of a wide range of techniques. The most common include manual soldering for small-scale tasks and automated soldering for production lines. There are two main types of leads used in through-hole soldering. These include radial and axial leads.

Thermal linkage- Thermal linkage refers to the surface area forming the points of contact between the soldering iron tip and the lead. A very small thermal linkage causes insufficient flow of solder and thus structurally-weak joints.

Tinning- This is a tip cleaning technique that utilizes what is known as a tinner. The working of a tip tinner is relatively simple. Once an iron tip is coated with unwanted material, mostly solder from operations, it is dipped into the tinner at the temperature normally attained during soldering. Due to its reducing characteristics, the tinner will stick to the tip of the iron thus forming a bright and shiny surface and removing all other unwanted material. Tinners, unlike a wide range of other soldering pastes are almost hazard-free and present very few if any personal risks.

thermostat

Soldering Jargon III

Thermal mass- This is its unique ability to absorb and to store heat energy. The thermal mass of an element determines how much heat is needed to solder it and for how long the item will be exposed to that level of heat.

Tomb-stoned component- This is a defect in soldering where a component’s lead is suspended or elevated above a printed circuit board surface. This results from the problem of pad lifting. Lifted pads are rare but possible occurrences. It basically involves pad lifting from the printed circuit board once soldered. This does not happen with techniques such as the through-hole technique but is very possible with surface-mount techniques.

Thermal conductivity- This is the standard of measure of how well heat will be conducted through a give surface area of a metal. This is usually derived for a particular heat source and not just any type of heat.

Thermal shock- This is the damage caused to components or surfaces once they are exposed to sudden and rapid changes in temperature. A common example is the practice of cleaning a hot soldering iron tip with a damp cloth. This causes the tip to rapidly contract. This is known as thermal shock. Preheating surfaces prevents the effects of this.

Thermal expansion mismatch- This is the absolute difference between the thermal expansions of two components. Thermal mismatches often result in various soldering-related defects especially if the materials are to be soldered together.

Thermostat- This is knob that controls the temperature regulation mechanism within a soldering iron and other soldering equipment.. This component regulates the maximum temperature your soldering iron can achieve depending on your settings and preferences. Thermostats work by cutting off power supply to the soldering iron and thus preventing further increments in the heat output at the tip.