Electronics and C om puterSystem s Engineering BASIC HAND SOLDERING BASIC HAND SOLDERING MULTICORE SOLDER MULTICORE SOLDER most common type for most common type for hand soldering has a hand soldering has a composition of Tin composition of Tin (Sn60) and Lead (Sn60) and Lead (Pb40), with a diameter (Pb40), with a diameter of 0.71 mm of 0.71 mm contains internal core contains internal core of non-corrosive Rosin of non-corrosive Rosin Mildly Activated (RMA) Mildly Activated (RMA) flux flux has a ‘plastic’ stage has a ‘plastic’ stage between the melting and between the melting and solidifying stages solidifying stages
BASIC HAND SOLDERING MULTICORE SOLDER most common type for hand soldering has a composition of Tin (Sn60) and Lead (Pb40), with a diameter of 0.71 mm contains internal core of non-corrosive Rosin Mildly Activated (RMA) flux has a ‘plastic’ stage between the melting and solidifying stages. - PowerPoint PPT Presentation
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Electronics and Computer Systems Engineering
BASIC HAND SOLDERINGBASIC HAND SOLDERING
MULTICORE SOLDER MULTICORE SOLDER most common type for hand most common type for hand
soldering has a composition of soldering has a composition of Tin (Sn60) and Lead (Pb40), Tin (Sn60) and Lead (Pb40), with a diameter of 0.71 mm with a diameter of 0.71 mm
contains internal core of non-contains internal core of non-corrosive Rosin Mildly corrosive Rosin Mildly Activated (RMA) fluxActivated (RMA) flux
has a ‘plastic’ stage between has a ‘plastic’ stage between the melting and solidifying the melting and solidifying
stagesstages
‘‘Dry joints’ are caused through:Dry joints’ are caused through: movement of joint during movement of joint during
TIPSTIPS appropriate size and width is appropriate size and width is
determined by the size of the determined by the size of the connection to be madeconnection to be made
ideally 2/3 to equal the ideally 2/3 to equal the diameter of the paddiameter of the pad
tips should be correctly 'tinned’ tips should be correctly 'tinned’ at all times, by adding a small at all times, by adding a small
amount of solder to the hot tipamount of solder to the hot tip
Electronics and Computer Systems Engineering BASIC HAND SOLDERINGBASIC HAND SOLDERING
LEAD FORMINGLEAD FORMING minimum distance from the minimum distance from the
end of the component body to end of the component body to the start of the lead bend is the start of the lead bend is usually 2 lead diameters or usually 2 lead diameters or 1.5mm for hand bending 1.5mm for hand bending methodsmethods
without undue pressure hold without undue pressure hold the component lead with the the component lead with the pliers and bend the lead pliers and bend the lead protruding beyond the pliers protruding beyond the pliers with a finger until a 90 degree with a finger until a 90 degree angle is formed.angle is formed.
if damaged discard componentif damaged discard component
Electronics and Computer Systems Engineering BASIC HAND SOLDERINGBASIC HAND SOLDERING
off the PCB (0.3 - 3.0mm)off the PCB (0.3 - 3.0mm) Axial-leaded Axial-leaded loaded with the loaded with the
body of the component very body of the component very close to the PCB (0.3 - 3.0mm)close to the PCB (0.3 - 3.0mm)
Electronics and Computer Systems Engineering BASIC HAND SOLDERINGBASIC HAND SOLDERING
BENDING AND MOUNTING OF BENDING AND MOUNTING OF COMPONENTSCOMPONENTS
mounted centrally between mounted centrally between the holesthe holes
resistors mounted so colour resistors mounted so colour code orientated in the same code orientated in the same directiondirection
polarised components polarised components should be orientated so that should be orientated so that polarity symbols (+ or - ) and polarity symbols (+ or - ) and component value are visiblecomponent value are visible
Electronics and Computer Systems Engineering
BASIC HAND SOLDERINGBASIC HAND SOLDERING
LEAD TERMINATIONSLEAD TERMINATIONS
TYPE 1 FULLY CLINCHED –TYPE 1 FULLY CLINCHED – bend the lead flat against the pad bend the lead flat against the pad trim the lead to a length of between 1-2 trim the lead to a length of between 1-2
lead diameterslead diameters Used in High Quality/High Reliability Used in High Quality/High Reliability
military or life support applications military or life support applications difficult to reworkdifficult to rework
TYPE 2 SEMI-CLINCHED –TYPE 2 SEMI-CLINCHED – bend the lead to an angle of approx. 45bend the lead to an angle of approx. 45 Cut to a minimum of 0.5mm and a max. Cut to a minimum of 0.5mm and a max.
of 1.5mm, or between 1-2 lead diameters of 1.5mm, or between 1-2 lead diameters Used for commercial applications Used for commercial applications ease of de-soldering ease of de-soldering
TYPE 3 RIGID LEAD TERMINATION – TYPE 3 RIGID LEAD TERMINATION – straight through terminationstraight through termination Cut to a length of min. 0.5mm and max. Cut to a length of min. 0.5mm and max.
of 1.5mm, or between 1-2 lead diameters of 1.5mm, or between 1-2 lead diameters
Electronics and Computer Systems Engineering BASIC HAND SOLDERINGBASIC HAND SOLDERING
CONSTRUCTING A GOOD CONSTRUCTING A GOOD SOLDER JOINTSOLDER JOINT
Figure a) the amount of solder Figure a) the amount of solder applied is minimal and may applied is minimal and may result in a poor electrical result in a poor electrical connection over time.connection over time.
Figure b) shows the optimal Figure b) shows the optimal solder joint that has good solder joint that has good wetting between component wetting between component lead and PCB pad.lead and PCB pad.
Figure c) indicates an Figure c) indicates an excessive amount of solder excessive amount of solder has been applied to the has been applied to the connection.connection.
Electronics and Computer Systems Engineering BASIC HAND SOLDERINGBASIC HAND SOLDERING
CLEANINGCLEANING a process of removing
contaminates before and after soldering
ensures good mechanical/electrical connection
Three different methodsThree different methods: Mechanical - scourer or bristle