I recommend that you read through these instructions at least once before actually beginning work due to a number of saftey concerns and possible pitfalls you may encounter which are addressed throughout.
In this guide I will be showing a simple method for recovering various kinds of useful electronic components from old or broken consumer electronic devices. The goal of these instructions is to demonstrate a less involved method of recovering components from circuit boards commonly found in many types of electronic devices.
Benefits over other methods:
Traditional methods of recovery commonly use a hand held soldering iron combined with copper wick or an extraction tool used to remove solder from around the desired components "pads" or "footings", this can frequently be cumbersome and time consuming due to the need for stable hands and small tools, as well as ample light and magnification, making it difficult to recover large numbers of parts in a short period of time. The method I demonstrate requires no small tools or fine motor coordination making it accessable to people of all skills.
These instructions are intended for a wide audience within a specific field of interest. It is expected that if you are reading this you have some interest in electronics hacking and development, but I attempt to make no assumtions about prior experience when working with tools, compents, or knowledge of terminology outside of the basics expected of someone interested in this topic. It is my hope that you find this guide useful whether you've just begun to learn about how electronics and circuits work, if you're a weekend hacker looking to save money by reusing parts from old electronics, or an experienced veteran looking to cut down on the time it takes to de-solder components from PCB's (Printed Circuit Boards).
Step 1 - Safety considerations
Step 2 - Required and recommended tools
Step 3 - Workplace requirements and preparation
Steps 4 to 8 - Body of instructions
Step 9 - Recommended next steps
Step 1: Safety Considerations
NOTE FOR READERS UNDER 18, I recommend asking for the assistance of a parent or other adult when working through these instructions as there are a number of safety concerns to be aware of when working with solder and heat guns.
NOTE ON EYE PROTECTION, Solder can often spit when heated and therefore it is recommened some form of eye protection is worn throughout the process.
As a general guide, this document (you can also find the pdf attached) outlines a number of "best practices" when it comes to working with solder in any situation or project. Below I will outline specifc points that are of higher concern when using the tools detailed in the following guide.
Fumes and Ventilation
It is always important to consider your ventilation and air flow situation whenever working with solder. It is impossible to know what sort of metal solder were used in the original assembly of the parts you may be working with, therefore it is very important to implement measures aimed at avoiding the inhalation of fumes generated when the solder is heated. MAKE SURE YOU WORK IN A WELL VENTILATED AREA SUCH AS A GARAGE, WORKSHOP, OR ELECTRONICS LAB WITH A VENTILATION HOOD. USAGE OF AIR FLOW IMPROVING DEVICES SUCH AS FANS OR DUCTING IS HEAVILY ENCOURAGED TO AID IN QUICKLY REMOVING POSSIBLY HARMFUL FUMES FROM THE WORK AREA. If you would like ideas on creating effective fume removal tools, I encourage looking online for guides and plans created by experienced electrical designers. For the purposes of this guide two fans, one used to remove fumes from the workspace, and another used to circulate outside air should be adequate for preventing inhilation or build-up of fumes. If at any time you begin to experience a headache, dizziness, naseua, or blurred vision, stop working immediately and move to a different room or outside and breath slowly, these symptoms can indicate you do not have adequate ventilation in your workspace.
Fire, Heat, and Burns
As part of this guide you will be working with tools capable of reachine over 750 degress Farenheight, therefore it is important to follow proper safety methods when handling these tools. Extensive safety instructions are provided with all heat guns and should be fully read and well understood before first use of the tool. Since every model of heat gun is different I cannot give specific advice on safety measures to take with these tools, but as a general rule, do not leave them on when not in your hand, do not set them on flameable surfaces or objects, and never place any part of your body in front of the end of the heat gun as this could result in severe burns.
Disposal of Waste
Please be concious of the environment and properly dispose of all electronics waste when you are done. Electronics recycling centers are common throughout the US, please use them to dispose of unrecovered parts or left over boards when done.
Step 2: Required and Recommended Tools, Require Parts
- Heat gun, must be capable of reading at least 250 degrees Farenheight
- Needle nose pliers (tweezers/forceps can be used as well, but the insulated grips of pliers is useful in preventing excess heat transfer to your hand)
- A box/tub/container to hold recovered parts
- A vise (Two large books or pieces of wood may also work, they just need to be able to hold the PCB you're working with in an upright and steady position on your work surface)
- Ventilation equipment (please see Safety considerations)
- Safety glasses (please see Safety considerations)
- a fire extinguisher (please see Safety considerations)
- Magnifying device
- Adjustable lamp or other directional light source
One or more printed circuit boards, with all wires and external connections removed or cut. Please refer to the following image as an example of a prepared board. It was removed from a non-functional portable radio. It was necessary to trim/cut the connections from the board to things such as its power supply and various switches and knobs on the body of the radio. Small sections of wire are still visible and attached which is acceptable, just attempt to reduce the amount of plastic you leave on the board as these will melt when the heat gun is directed at the board for extended periods of time.
Step 3: Workplace Requirements and Initial Set-up
You will need access to a number of electrical outlets in your workspace. Use them to power ventilation fans as well as the heat gun and any lighting you may be using to illuminate your work. Place your parts container, pliers, fire extinguisher, vice, and parts board near where your heat gun and ventilation are set-up
You will begin by setting up your parts board inside of your vice. If you do not have a vice and are using two books or blocks of wood see the included image for an example using textbooks as fixtures. The only requirements for the set-up are that you can see and easily access both sides of the board at the same time. One of your fans should also be set up directly behind where you will be working to make sure fumes are properly removed, refer to the image again to see my example configuration.
Step 4: Identify Which Part You Wish to Remove
Look over the board you are working with, find a part on the surface which you have a desire to recover, such as a resistor or capacitor. I will be removing the capacitor indicated in the picture from my board. It may be useful to mark its location on the back side of the board with a marker so that you can be sure to heat the right spot. I've circled in marker the "feet" of the capacitor I am removing to help me identify it in the next steps.
Step 5: Grab the Part With the Pliers
Once you have identified the part you're removing you should take the pliers in one hand and place them on the part, gripping gently so you dont damage it.
Step 6: Start the Heating Process
In your other hand pick up and turn on the heat gun, turning it to any setting which will reach at least 500 degrees.
Point the nozel of the gun at the spot you marked on the side of the board opposite your pliers. Since the gun "blows" heated air, you will need to hold the gun in position for a few minutes to completely melt the solder, it will begin to look more fluid and possibly begin to emit fumes when it has become completely liquid.
Move to the next step as you continue heating the solder on the back of the board.
Step 7: Pull the Part Off of the Board During Heating
As you continue to heat one side of the board you should be gently pulling the part away from the board from the other side.
Eventually the solder will be fluid enough that you will be able to full remove the part with little effort.
Place it in your storage bin for safe keeping.
Step 8: Repeat Steps 4 Through 7 for Each Additional Part
At this point you can begin repeating the previous 4 steps for each additional part you wish to remove.
NOTE: Some parts may have large "footprints" meaning they may have many pins spread over a large area. For these parts you must make sure all the pins have their solder melted at the same time, otherwise only a few will come free when you attempt to remove the part. It may be required that you move the heating gun in a back-and-forth or figure-eight motion so that you evenly heat a larger area.
Step 9: Recommended Next Steps
Once you have successfully removed all the parts you wished to recover you can put away your tools and clean up your workspace.
You will have ended up with a box or container full of assorted components, but having them all together may make finding exactly what you need difficult when it comes time to use them for a project. Additionally some of the components may have gone bad, especially if you are recovering parts from a device that was no longer working. I recommend the use of a multimeter for testing of the simplest of components, integrated circuit chips will be more difficult to test.
Once you have determined which parts work and which dont, you can sort them into groups by their values which are frequently labeled on their exterior, but in the event they are not, again use a multimeter to test them. For integrated circuits you will want to lookup online the part number which is printed on the face of the chip. Google is a good resource since there is no "centra" repository of chip part numbers and manufactures.
I hope you've found this guide useful in simplifying the process of removing usable components from old or broken electronics! If you do frequent projects with electronics this method can save a significant amount of money and time on parts and their recovery. Keep hacking and have fun (safetly)!