Bob Loblaw has had about ten of these cheap halogen work lamps over the years. They look like a steal in your local hardware store, only to find out later that the bulbs they require cost almost as much as the unit itself. Not only that, but the lamps get hot as hell, use a lot of electricity (Bob guesses), and the bulbs are fragile and cannot be touched without gloves or some other barrier lest ye oil up and damage said expensive bulb. Aside from that, they are handy to have. So here's an instructable to convert one of these units into a CFL lamp that puts out almost as much light, with far less heat, longer lifespan, and less energy consumption.
Step 1: What you'll need
For this project, Bob assumes that you have one of these types of lamps gathering dust in your garage or closet because you were fed up with paying $15 for a little bulb. To get started, you will need:
A standard light bulb receptacle, Bob found a rubberized one at the store for $4.95 that already had the wires attached.
An "L" bracket, about 1" on each side, a pack of four runs about $3.00
A hose clamp, about 1.5" diameter (big enough to fit around your light bulb socket)
A metal hole cutter, sized to match the diameter of your light bulb socket
Drill & bits
Nut drivers (if you have them)
Step 2: Removing original buld assembly
Bob Loblaw thinks it would be best to not have your light plugged in from here on out. First, open the lamp using the screw at the top of the lamp. The glass front will hinge down and you will now remove the halogen bulb by pulling or prying it from the bulb holder. Next, locate and unscrew the screw holding the reflective foil in place. Remove the foil, which should expose the original bulb holder as shown in the first picture below. Unscrew the bulb holder from the lamp, and either cut or unscrew the wires connected to the bulb holder. You will want to leave as much wire as possible. Strip the ends of each wire approximately one third of an inch.
Step 3: Drill a hole
Next, you will drill a hole in the top of your lamp to fit the standard light bulb socket through. This is required because there's not enough room in the lamp for both the bulb and a socket. Bob used a metal hole cutter with a pilot bit to drill in the approximate middle of the top of the lamp. Place your socket on top of the lamp and use a marker to outline the area to be cut. The lamp Bob modified was aluminum and was very easy to drill through.
Step 4: Mount the bulb socket
Once the hole was cut, Bob installed an "L" bracket on the front side of the top of the lamp to hold the socket in place. Drill a hole in the top of lamp that will allow for the lamp socket to be held in place. Bolt the L bracket in place and use a lockwasher if you have one. Bob didn't. Next, hold the socket in place and use a hose clamp (or zip ties if you like to half-ass) to hold the bulb socket firmly in place. Drill two holes as shown in the picture for the wires to enter the lamp.
Step 5: Wire it up
After running the bulb socket leads into the lamp, connect the leads to the respective wires that had connected to the original halogen bulb assembly. Connect the wires with an insulated connector of some sort, and then wrap in electrical tape to be on the safe side since the lamp itself is metal. At this point you can install a bulb to make sure it's functional before putting it back together.
Next, re-attach the halogen bulb holder, which acts to hold the wires at the back of the lamp and also provides a mounting hole for the reflective foil.
Step 6: Final steps
Before re-installing the reflective foil, you will need to cut a hole in it to allow for the bulb to enter the socket. The foil is pretty thin, and can be cut with scissors or even a box cutter. Bob used a screwdriver to punch a hole through the foil and then used scissors to cut the hole big enough for the bulb threads to pass through. Now you can re-install the foil and screw in the bulb. Bob has tried nearly every CFL on the market and really likes the Philips Marathon 60 for its incandescent-like color. Bob has bought a metric assload of these bulbs. Bob also thinks you should look on ebay for these bulbs since they cost about one third of retail on ebay.
Step 7: Done diddly done.
The lamp should now be complete-test it to make sure that it turns on and off with the switch on the lamp. Bob's didn't work at first because the crimped wire connections hadn't been crimped hard enough. Your new lamp should now last a long time and is now more energy efficient with less heat.