Introduction: How to Solder Through-Hole Parts

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About: Electronics enthusiast, vlogger on youtube.

In this Instructable I’m gonna show you how to solder through hole parts. I’m gonna take you step by step through the procedure as well as give you several tips & tricks that should bring your soldering skills to a new level. This tutorial is tailored towards soldering through hole parts but if you would like to learn how to solder smd parts you can checkout my other instructable.

Step 1: Watch the Tutorial Video!

The video describes the entire process of soldering through-hole components, including tips&tricks so I recommend watching the video first to get an overview of the process. Then you can come back and read the following steps for more detailed explanation.

Step 2: Order the Supplies Needed

For the soldering job you are going to need some supplies like: solder wire, solder paste, flux, soldering iron so here are a few links to help you find those items. Go ahead and order these to have them ready when you start soldering. You might already have some of these supplies if you have been doing some previous soldering.

Step 3: Start by Cleaning the Surfaces

The first step is to make sure we have clean surfaces, if the PCB is not clean, take some isopropyl alcohol and give it a wipe. We also want to make sure our soldering iron tip is clean, use the brass sponge until the tip is clean.

Step 4: Feed Just Enough Solder to Get a Perfectly Looking Solder Joint

Next we position ourselves for the job and one of the mistakes I see often is adding solder to the tip before the actual soldering of the pin. That will evaporate the flux creating nasty oxide residue on the tip so the solder will not flow nicely onto the joint.

The correct way to do it is to heat up the joint, bring it up to temperature and then feed the solder wire. For small solder joints, with the right temperature and a good solder wire with decent flux core you won’t need any additional flux. It’s important to have a tip shape that will help you get a greater contact surface with the pad and pin to transfer heat as efficiently as possible. Don’t use just a thin pointy tip, that one will have a very small contact surface and poor thermal mass.

Now feed just enough solder to get a perfectly looking solder joint. When the solder quantity is just right, it should look something like this. It should have this conical shape, and the solder should adhere to both the component lead and the pcb pad

Step 5: Clean the Board When Finished

Next you can trim the component leads with a pair of side cutters. Use eye protection, because component leads tend to fly off when trimmed with a pair of sharp side cutters. I don’t usually wear eye protection but I place my hand over the board while cutting the leads thus catching any flying leads.

The last step is to clean the solder joint but this step is optional depending if the solder/flux used is a no clean variety or not. If the flux is no clean, than it can be safely left on the PCB and you only need to clean it if you wish to have a perfectly clean board. However I like cleaning my boards for a better finish, I spray some pcb cleaner, I use an ESD safe brush and then I wipe the pcb clean with some paper towels.

Step 6: Tips & Tricks

I would also like to give you a few hints on the assembly of through hole boards and I’m referring to the actual placement and orientation of parts on the board.

  1. start with the smallest components first, they will be closest to the board and it’s easier to get them place first.
  2. try to place similar parts in the same orientation to make it easier to read their values.
  3. pre-form component leads by bending them with a special tool.
  4. bend the leads on the back of the pcb before soldering to keep the part in place while soldering.
  5. use IC sockets for integrated circuits if possible, it will be much easier to debug and repair a board with sockets.
  6. if you want to increase the heat dissipation capability you can solder through hole components higher off the board thus you gain the advantage of the extra length of leads that will act as a heatsink for the component and you also get extra airflow under the part.
  7. if you plan to solder some wires to a pcb it helps to pre-tin the wires before soldering. Next when soldering them to the pcb the solder coating the wires will melt and combine much easier with fresh solder from the pad.

With a bit of practice and following these tips and tricks you should be getting excellent results in no time. Soldering really isn’t something complicated, I’m pretty sure everyone is capable of doing it like I said with a bit of info and practice. So, that was all, I hope this video was useful if so please leave a comment or hit the like or dislike button to send me some feedback.

Step 7: Conclusion

With a bit of practice and following these tips and tricks you should be getting excellent results in no time. Soldering really isn’t something complicated, I’m pretty sure everyone is capable of doing it like I said with a bit of info and practice. So, that was all, I hope this video was useful if so please leave a comment or hit the like or dislike button to send me some feedback.