Soldering Through-Hole Components Into a Circuit Board By: Evan Wall Advanced Organizer This document is directed at Pennsylvania State University electrical engineering students in the course EE210. This document will help prepare EE210 students for the final project in which they must solder many components into a through-hole circuit board. This document will discuss proper procedure for soldering these components. This document is broken up into 4 parts; the advanced organizer, Background information, Items required, safety tips, instructions, conclusion, and works cited. The advanced organizer is first so that the context and the organization may be established for this document first, then the required items are provided so that they may give context for the safety precautions, then any necessary safety precautions are taken before the dangerous activities begin in the instructions. The instructions given with a larger font so that they can be read more easily. The conclusion elaborates on the purpose of this document, and where to gain more knowledge of this subject. The works cited is the final item as it is not necessary to achieving the purpose of this document. Background Information Soldering is an ancient and sacred art that has been around for thousands of years. Soldering is a form of metal working which has been dated back roughly five thousand years. The ancient Egyptians and Trojans were the first known groups to conjoin two metals together using a technique similar to soldering. It was not until roughly four thousand years ago that soldering was truly born through the discovery of tin. Tin allowed for two metals to be conjoined by soldering because tin had such a low melting point that the tin would become liquid before any other metal would even be damaged by heat. The ancient Romans were known to have some of the most incredible feats of soldering. They soldered together 400km long lead pipes, furnaces, armor, and works of magnificent golden art. Recent developments over the past hundred years has led to advances in soldering technology and the mass production of soldering equipment which is now widely used in the electronics industry.[1] Terminology Leaded: A component which was leads or wires extruding from it. Through-hole: A hole in a circuit board to which a component may be attached. A typical through-hole has a metal pad around the hole to encourage conductivity and create a location for the solder to bond to. Clips or “Third-hands”: A device with clips and a heavy metal base which is used to suspend items in a specified orientation and position.

Items not shown Leaded item to be soldered Well ventilated location Work bench Metal file (optional) Safety Goggles Circuit board with through-hole sites Wire cutters Wire strippers (only necessary if soldering wire.) Soldering iron (low wattage; Watts) Required Items

Set of clips or set of “third hands” (anything which will hold components in place) Solder (lead-free) Damp sponge or damp paper towel Safety Tips Warning: Always wear safety goggles when soldering. Getting hot solder on your cornea will instantly result in blindness in one eye. Do not contact the heated part of the soldering iron to anything other than: solder, the stand, or the items which are being connected. Do not perform any tasks other than soldering when holding the soldering iron. Use a low power soldering iron to help prevent serious burns. If burnt immediately place soldering iron in stand and unplug soldering iron then consult a person trained in first aid or a medical professional.

Instructions Preparation 1. Clear an area on the workbench of all items which are not in the required items list. 2. If the soldering iron is dull or has any materials covering the tip, file of any extra material and file until the soldering iron has a pointed tip once again. 3. Place soldering iron on soldering iron stand. 4. Plug in soldering iron. If the soldering iron has a temperature setting, set to high or medium-high heat. 5. Wait for soldering iron to heat up. This may take anywhere from 2 to 10 minutes. You can check the heat by lightly touching the soldering iron to a damp sponge. If the water sizzles, then the soldering iron is hot enough. You may also check the temperature by trying to melt a small amount of solder with the soldering iron. 6. If you are soldering a wire to the circuit board, make sure the wire is stripped of its rubber coating to allow for at least a half inch of exposed wire. Step 6: Wire coated with rubber and ½” of exposed lead. Caution: Read the instructions thoroughly before beginning any soldering. You should not be soldering and trying to read the instructions, or doing any kind of multitasking while soldering. Step 5: Checking the temperature of the soldering iron

7. Take the component that is going to be connected to the circuit board and place it into the hole in the circuit board, make sure that the component is in a position similar to its final position. Soldering 8. Once the soldering iron is hot, connect the soldering iron to the wire or lead of the component which will be connected to the circuit board. 9. Connect the solder to the lead, do not connect the solder to the soldering iron, this will cause a poor connection and a weak solder joint. Sustain the connection of solder and lead until the solder begins to melt onto the lead. 10. Guide the melted solder to the copper pad of the circuit board. Use only enough solder to form a small cone at the connection between the copper pad and the lead. 11. Wipe any extra solder from the soldering iron onto a damp sponge or damp paper towel. 12. Place the soldering iron on the soldering iron stand. 13. Use the wire cutters to remove the part of the lead extending beyond the board on the opposite side of the component. Steps 8 and 9 [2] Step 11: Wiping away extra solder on a damp sponge Step 13: Snipping extended lead

14. Repeat steps 7 through 11 for each lead and component which will be added to the circuit board. Clean up 15. Unplug soldering iron. 16. Let the soldering iron cool for about 20 minutes, and wait until the soldering iron is at room temperature. Flowchart of steps

Conclusion Once the soldering iron is cool you are all done. Congratulations! Hopefully you didn’t sustain any serious injuries or damage. Now that you know the steps necessary for proper soldering and you know the required safety precautions, you are one step closer to becoming a full-fledged electrical engineer. When first learning soldering it is highly unlikely that the finished project will look nice, and you will likely have to resolder multiple components. As you gain experience with soldering your results will drastically improve and you will be able to solder faster, more effectively, and the final product will look much nicer as well. If you would like to learn more you may visit this website. This website is a tutorial which goes into much more detail regarding soldering. It covers more advanced topics like using soldering guns and soldering cables together. This website teaches you soldering in a much more diverse array of projects. Good luck on your future soldering endeavors and may the black smoke of your circuits forever flow in your favor. Citations [1]"Soldering History." Kurtz Ersa. ERSA, n.d. Web. 10 Apr [2]"Electronics Primer: How to Solder Electronic Components." Electronics Primer: How to Solder Electronic Components. Science Buddies, n.d. Web. 10 Apr