Reply to thread

Message: <blockquote data-quote="laal" data-source="post: 8537142" data-attributes="member: 94459">Soldering and Desoldering ToolsSoldering IronA soldering iron is a tool normally used for applying heat to two or  more adjoining metal parts such that solder may melt and flow between  those parts, binding them securely, conductively and hermetically.<img src="http://lh6.ggpht.com/_8JZhVVmpICU/S8T9vXycTTI/AAAAAAAAANc/Tl45cTrzFhI/soldering%20Station.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" />A  soldering iron is composed of a heated metal tip and an insulated  handle. Heating is often achieved electrically, by passing an electrical  current (supplied through an electrical cord or battery cables) through  the resistive material of a heating element. Another heating method  includes combustion of a suitable gas, which can either be delivered  through a tank mounted on the iron (flameless), or through an external  flame.<img src="http://lh5.ggpht.com/_8JZhVVmpICU/S8UB4phx0oI/AAAAAAAAAN4/kiQutrnE3yA/soldering%20smd.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" />Some soldering irons heat up and cool down in a few seconds, while others may take several minutes.Soldering LEAD Soldering lead is used to bond or connect electronic components. Solder is a fusible metal alloy with a  melting point or melting  range of 90 to 450 degree Celsius  (190 to 840 °F), used in a process  called soldering  where it is melted to join metallic surfaces. It is  especially useful  in electronics .  Alloys that melt between 180 and  190 °C (360 and 370 °F) are the most  commonly used. By definition,  using alloys with melting point above  450 °C (840 °F) is called  brazing. Solder can contain lead and/or flux but in many applications  solder is now lead free.<img src="http://lh3.ggpht.com/_8JZhVVmpICU/S8UBa8TyjII/AAAAAAAAANw/lH9TmxY33TQ/soldering%20lead.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" />While it is possible to do some wiring without soldering connections,  soldering is the preferred approach. Proper soldering is easy with the  right tools and techniques. One item that is critical is the right  solder.  DO NOT use the environmentally friendly lead free solders, they  don't work worth a damn. Even in carefully controlled industrial  conditions, lead free solders produce inferior connections. As much as  the politicians backed by environmentalists would like to, they can't  legislate metallurgy.Soldering PasteSolder paste (or solder cream) is used for connecting the terminations  of integrated chip packages with land patterns on the printed circuit  board. The paste is applied to the lands by printing the solder using a  stencil, while other methods like screening and dispensing are also  used. A majority of defects in mount assemblies are caused due to the  issues in printing process or due to defects in the solder paste. An  electronics manufacturer needs to have a good idea about the printing  process, specifically the paste characteristics, to avoid reworking  costs on the assemblies.<img src="http://lh6.ggpht.com/_8JZhVVmpICU/S8UBazV5IYI/AAAAAAAAAN0/irf0AEmQiUQ/soldering%20paste.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" />Characteristics of the paste, like viscosity and flux levels, need to be monitored periodically by performing in-house tests.Soldering flux Soldering flux is just a safe, convenient  acid for dissolving the oxide skin off the metal you want your  solder to wet well. Also dissolves oxide off the liquid solder, making  it less crusty and therefore more shiny.<img src="http://lh4.ggpht.com/_8JZhVVmpICU/S8UBatbE5UI/AAAAAAAAANs/UtKeWLf5Eyk/soldering%20flux.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" />"Acid"  flux is the stronger class of flux; it has something like hydrochloric  acid in it. (The paste form has zinc chloride.)This is  good for making difficult oxides dissolve so difficult metals like  stainless steel can be solder-wetted.But the acid can hang  around later trying to corrode the metal it just cleaned for you.So  for electronic stuff we mostly do not use it.If we do, we scrub  it off with things like toothbrush, water, soap, alcohol, baking soda, to  minimize acid residues.The flux built into most  solder wire is called rosin flux.I think it is an organic acid  (so is vinegar, and tart-tasting "citric acid"),stuck onto larger  molecules that melt only at soldering temperatures.That is the  clear yellow-brownish plaque that sits on the solder's surface when you  are done.It does the same stuff as acid flux, but it is  milder two ways.It is only strong enough to reduce weakly  oxidizable metals like copper, tin, lead, silver.So it is  just strong enough for electronics use, but not for soldering to  stainless steel or iron or anything with chrome or aluminum.And  rosin-flux goes back to its plastic-like solid form after use, so it  does not act very corrosive to the metals later on.So we  do not need to clean it away carefully.It can be cleaned away if  you want to work at it, with brush-scrubbing and the right "polar  solvents"."Flux remover" is sold in spray-cans for this. Rubbing  alcohol with a dash of dish-soap sort of works for me.Try  it and see what it looks like.  Soldering WickA solder wick (also desoldering wick or desoldering braid) is a tool   for removing solder from any solder joint. Usually, it is a roll of   fine, braided 18 to 42 AWG wire, typically oxygen free copper, which has   been treated with a rosin solder flux.<img src="http://lh4.ggpht.com/_8JZhVVmpICU/S8T9vCqDmPI/AAAAAAAAANY/-i-haTlSJEA/desoldering%20wick.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /><a href="http://en.wikipedia.org/wiki/File:Solder_wick-close_up-full_PNr%C2%B00103.jpg" target="_blank"><img src="http://upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Solder_wick-close_up-full_PNr%C2%B00103.jpg/220px-Solder_wick-close_up-full_PNr%C2%B00103.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></a>  Close up to a piece of solder wick<a href="http://en.wikipedia.org/wiki/File:Solder_wick-close_up-part_PNr%C2%B00104.jpg" target="_blank"><img src="http://upload.wikimedia.org/wikipedia/commons/thumb/0/07/Solder_wick-close_up-part_PNr%C2%B00104.jpg/220px-Solder_wick-close_up-part_PNr%C2%B00104.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></a>  Close up to the netting of a solder wick<a href="http://en.wikipedia.org/wiki/File:Solder_wick-close_up-solder_impurities_PNr%C2%B00112.jpg" target="_blank"><img src="http://upload.wikimedia.org/wikipedia/commons/thumb/3/36/Solder_wick-close_up-solder_impurities_PNr%C2%B00112.jpg/220px-Solder_wick-close_up-solder_impurities_PNr%C2%B00112.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></a>  To  remove solder with it, one presses the wick onto the solder joint to  be  removed and then heats the wick portion that is on the connection  with  the tip of a soldering iron. As the rosin melts onto the wick and  the  connection and the solder reaches its melting point the solder  rushes  via capillary action onto the clean copper braid. Once  everything has  melted and the solder fuses with the braided copper, the  wick is lifted  along with the solder and is then cut off and disposed  of.</blockquote>

Verification: Asuwa dahayen wadi kalama keeyada?

Top Bottom