This is a simple DIY way to make a reflector for a compact florescent (CFL) bulb.
There are many situations where you are lighting a plant and half the light coming from the bulb is going out your window, on the floor, or into you living room. A lot of this wasted light can be redirected back at the plant with a simple reflector. With CFL’s the best light comes out the side of the coil, therefore a standard shop light reflector is not very affective. Fortunately it is possible to make a effective CF reflector in under 10 min.
You will need:
1- 16oz beer can (12oz work, but not as well for bulbs over 15 watts)
1- CF bulb, I used a 26watt one
1- Clamp light (this will work for other fixtures too)
tin snips or scissors you don’t care about
Take apart clamp light. With out a bulb in it (and not plugged in!!!!) twist the reflector off. It is threaded into the plastic, and it should come off in 3 to 5 revolutions. Next loosen the wing-nut until everything falls apart. You should now have something like in this pic:
Cut up your can. I started by poking a hole with a pocket knife, then attacked it with scissors. First I cut a strait line the length of the can starting and ending just before the metal starts to curve in. Next I cut off the top of the can. On the bottom of the can I cut a slit almost half way around on each side, leaving about 1/2in. on the opposite side as the slit.
It should now look something like this:
Cut a hole in the bottom of the can that the light fixture will fit into. I did this by poking a hole with a knife and then pulling back the metal with pliers. Notice in the picture that the hole is not centered, instead it is located closer to the side which was cut. This will give more room for the bulb.
It is also important that the hole is not much larger than the plastic fixture. When opening the hole, the extra metal should not be removed, as it is necessary for the next step.
Put the clamp light back together, with the new reflector.
Slip the new reflector over the plastic fixture, and bend the excess metal so that is touches the plasic. Then reconnect the bracket that connects the clamp to the fixture so that it compresses on these flaps of metal. This is what will hold the reflector to the fixture.
If you are not using a clamp light this connection could be made with a hose clamp, or my favorite thing; annealed steel wire.
Fold the cut edges of the reflector.
Be careful with this step, it is sharp! Gloves may be a good idea, though it’s not as bad as most sheet metal, as aluminum is rather soft.
I bent a little under 1/2 in. of the edge over. This makes the reflector much stiffer, allowing you to bend it to the form you want.
At this point the reflector could be painted white, or better yet coated with silver Mylar. This can easily be attached with spray adhesive. Just cut the Mylar to size, spray, and stick it (read the directions on you spray adhesive)
Test it, and tweak it.
Bend the reflector so that it shines the way that is most useful for you.
For larger bulbs, like this 68watt CFL, a coffee can can be used.