A Different Soldering Class “Surface Mount Soldering” Nick Carter12/02/2016 This was taught at Nova Labs by Bob Coggeshall nova-labs.org Meetup Nova-Makers Reston. See notes page for this ppt. application. This was made for middle school students who in Tech. Ed. Classes are being introduced to soldering using a single sided PC board kit. This kit was a “decision maker” - random “YES” or “NO”.

Have you Noticed?? Soldering Can Be Smelly Peeuuu! Cool HOT Solder will stick to clean objects much better and conduct electricity better. The solder contains little strands of flux inside The heat turns the FLUX into a gas that we can smell. FLUX cleans dirt from the objects being soldered `

Why I Took THIS Soldering Class I have worked as an Electronics Engineer for 50 years but……….. I only soldered components with wires This class taught how to solder components with NO WIRES. I wanted to do it myself. The components are called Surface Mounted components because DUH…. They fasten to the board surface (need no holes) This class is not just for adults. Kids who can follow directions can come with their parents to learn this too.

How It Works The component are connected to the board with solder. It makes the electrical connection It “glues” the component onto the board Little beads of solder are made into a paste with “flux” The paste is put on the connection pad The component is placed on the pads with connection areas contacting the solder paste. The board and components are heated until the solder melts and joins the components to the board. Resistor paste Solder HEAT Circuit wire Component “wire” Paste

Bare Board and Components Solder Paste

Soldering the Components How are they heated? The whole board and components can be put in an oven Individual components can be heated with a hot air blower like a special hair dryer (but hotter) Once the solder melts and connects the components the heat can be removed Why don’t the components fall off? The paste is sticky when cool Surface tension pulls them to the board when the solder melts When they cool the solid solder “glues” them to the board For big components, additional glue can be used

Surface Mounting Soldering Station Hot air blower Soldering Iron Hot Air Nozzles & tools

Compare our Boards FIND THE>>>>>> Surface Mounted Through Hole Mounted FIND THE>>>>>> resistor capacitor transistor LED switch integrated circuit connector

Compare our Boards Surface Mounted Through Hole Mounted FIND THE>>>>>> capacitor Nope! Gotcha - haha integrated circuit resistor transistor LED switch connector

Putting the Solder Paste On Hand application Screen Printing

Why Do It This Way? Components are smaller boards can be smaller everything is cheaper. It is easier to do using machines for making a lot Putting the solder paste on – e.g. screen printing Putting the components on – robot with vacuum sucker to grip the components Continuous movement of boards through an oven to heat them.

Putting the Components on Robotic tool takes component from tape and puts it onto board paste location. Board Components are put on plastic tape, on reels

Heating the Boards Continuous reflow oven melts solder then cools board

Test and Repair We tested by connecting the battery More complicated boards are tested by machines and bad ones sent for repair or scrap