Module 1

SOLDERING

SOLDERING

 

Soldering is a technique for joining two or more metals together using a molten solder.  Solder is a metal with a lower melting point compare the other metals that are being joined.  Soldering is used in electronics, jewelry, pluming and many other types of craft and metal works.   The solder used to be a Lead-Tin alloy for many years until it was gradually replaced by other metal alloys due to health concerns associated with Lead poisoning.  For soldered joins to be strong, the filler metal must bond to all the joining surfaces.   Dirty and contaminated surfaces will not bond to the solder and therefore all joining surfaces must be cleaned before soldering.   FLUX is a paste compound that melts at a much lower temperature and flows easily to cover nearby surfaces.  It removes contaminants from joining metals and helps the solder to stick to clean, joining surfaces.  Another consideration is heating all joining surfaces sufficiently so that solder can flow and stick to them evenly.  Cold spots will cause the solder to solidify before sticking and not be attached completely to the surface.  This is called “cold solder failure” and it is a major cause of intermittent electrical problems.    BRAZING is a form of soldering that uses a filler with much higher melting point and is used for joining water pies and other joins that encounter high stress.

 

TOOLS

SOLDERING IRON or SOLDIERING GUN is a tool that is used for soldering electrical components and it has a temperature range between 600oF to 700oF.  High temperature beyond what is necessary will destroy delicate electronics.    We will be practicing soldering electronic components in this class.

Soldering Iron has a tip that becomes very hot and requires careful handling.  Soldering iron tips should be maintained regularly for proper soldering.

In addition to a soldering iron and solder, the following tools can be very helpful:

Cleaning sponge or brass wool, soldering stand to safely hold the soldering iron and a pair of clips with a heavy base commonly called “helping Hands” to hold various parts during soldering.

 

SAFETY

  • Always wear your safety goggles while soldering to keep accidental splashes of molten solder away from your eyes.

  • Wear long pants to protect your legs.

  • Always do soldering work in a well-ventilated area or under a fume extractor when in small areas.

  • Soldering irons will get VERY HOT and will cause severe burn. Be very careful and DO NOT TOUCH the tip or metal body parts near the tip.  

  • Do not leave a plugged-in soldering iron unattended, always unplug it when you are done.

 

SOLDERING TIPS

  • Let the soldering iron reach operating temperature.

  • Clean the tip using wet sponge or brass wool.

  • Tin the tip, use a bit of solder for this and wipe the excess solder.

  • Make sure surfaces to be soldered are clean, wipe and flux the tip as needed.

  • Heat the area for a few second and then touch the solder to both surfaces. Solder should flow and cover both surfaces.

  • Do not use more solder than necessary.

  • Remove solder wire first and then the iron tip.

  • Don’t move components until solder has solidified.

  • Do not overheat components, too much heat will damage them.

  • If it takes too long to solder components, something is not right, check your steps and components.

  • Inspect soldered connections for quality of the work.

  • Wipe the tip and tin as needed.

  • Unplug iron when finished.