CFL Tubes: Get Some Useful Parts!

Introduction: CFL Tubes: Get Some Useful Parts!

About: I am a young electronics hobbyist and enthusiast with plenty of information to share. I build things as a hobby and have been doing so for several years. I am also interested in computers, tools, gadgets, an...

CFL tubes are a variety of light bulbs which consist of a curly flourescent light and a built-in ballast. Sometimes the tubes stop working, but there are still plenty of parts in a CFL that can be salvaged. These components can be extremely useful to have around, especially the toroids and the transformers, which come from the ballast itself. The extraction process is relatively easy and the CFLs can be purchased for around five dollars (I got a four-pack of 40-watt bulbs for this price). In this Instructable I will show how how to get into compact flourescent tubes and retrieve the useful components for use in your projects.

Step 1: What Is Inside a CFL?

CFLs contain many standard components. The specifics of what is inside the tube depend on what CFL you get, but there will always be a small transformer, some transistors, a set of small capacitors, diodes, an electrolytic capacitor, and at least one inductor. Some CFLs may also contain power transistors and many of the parts you find will be rated for at least 200 V. The inductor rings are very small and are good for making joule thieves. Most capacitors will be film or ceramic. CFL tubes will also have surface mount diodes, capacitors, and resistors on the bottom of the ballast which are, for the most part, not worth salvaging.

Step 2: Stuff You Need

You will need the following items to take apart a CFL:
-Soldering iron
-Desoldering bulb
-Power tool (or hacksaw)
-The CFL itself

Step 3: Cut Open the CFL

Getting into the CFL is not hard if you have the proper tools, and to make life easier I highly suggest using a power tool (such as a dremel). Cut straight along the seam where the two halves of the CFL are joined. Make deep cuts or you will not be getting into the tube any time soon. MAKE SURE YOU DO NOT CUT THE FLOURESCENT LIGHT ITSELF, AS DOING SO MAY RELEASE MERCURY! After you have cut all the way around the tube, you can break it in half with your hands. The wires keeping the light connected to the board are flimsy and should break when you force the CFL open. When this process is completed you should be left with two halves: the useless side containing only the glass tube, and the side with the board which we will take the parts from.

Step 4: Extract the Ballast Board

When you look at the side of the CFL that contains the ballast, chances are you will see a loose plastic "rim" between the board and the side of the compartment it is contained in. This can be pulled out with a pair of needle-nose pliers. Once you have pulled the rim out you need to cut the wires leading from the ballast to the screw on the bottom of the CFL that normally fits into a light socket. The easiest way to do this is to tilt the board to one side so you can fit a pair of scissors into the gap. Use the scissors to cut one of the wies and then tilt the board to the other side so you can cut the other wire. The end result is a seperate board which can be lifted out of the casing and salvaged further. The rest of the tube can be discarded, but the light contains mercury so you may want to consult your waste maneagement facillity for more details.

Step 5: Desolder the Parts

To get the parts off of the board, simply desolder them by touching the solder on the back of the board with your iron and sucking up the molten solder with a desoldering bulb. To make things easier, start with the large electrolytic capacitor, as removing it will allow you to work with the board on a flat surcace.

Step 6: Use Your New Parts!

The electronic components you get from the CFL can be used in any projects that call for those parts. You can also use them in your own original projects. Better CFLs with a higher wattage are usually more rewarding and yield more parts, but are generally more expensive. If you keep the board intact you can use it as a (rather poor) flyback driver, and you can even use the curly light to construct a joule thief lamp!

-As always, I hope this Instructable has been informative. If you liked this project, be on the lookout for more Instructables by me.

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    5 Discussions


    3 years ago

    to Tell the truth, these appear to be capacitors!!! photos is a little fuzzy. any makring using uF or uH??? F is used with capacitors only & H is for an inductor.


    Reply 3 years ago

    You're right, these do look a little like capacitors. However, I do not think they are. There are a few distinct differences, including the number on the side and the color. Besides, there are usually only one or two electrolytic capacitors in CFLs, and are usually pretty lage, at least in terms of dimention. I think it is much more likely that they are inductors.


    4 years ago

    Nice instructable!

    I also salvage components from old CFLs... The only trouble I have is with the inductors... Not having acess to the right equipment to measure them, how to know they're value?... I have a few (like the photo below) marked 411203, 411801, 410801, etc, etc... I assume these are manufacturers codes, but I can't seem to find any information... Any clue?...



    Reply 4 years ago

    This is a very good question, as I have never bothered to find the value of these inductors. Search the part number if you think it will help, but you may have to measure the inductance yourself. I have never measured inductance, but according to various sources you can do so with a signal generator, an oscilliscope, and a resistor/capacitor. As it turns out, I know very little about these methods, so I suggest you research it further. Of course, you could also buy a meter instead.