OK, here are the tips on sputtering I was supposed to post yesterday, along with a couple of pictures.
Use Krylon Crystal Clear Acrylic spray. Don't shake the can before using because you don't want a smooth spray, you want droplets of paint to land on the reflector.
Sputtering is much easier to do when the can is nearly empty than when it's full, but with a little practice you can get the effect you want. Don't push the spray button down very far, and it helps to pull the button backward as you press (it allows better control).
Do all spraying outdoors for the sake of your health. Practice spraying in the air until you can make tiny droplets come from the can without any smooth spray. You should master this very quickly. With a full can you'll only be able to get the droplets to spray about a foot in distance. With a near empty can they'll go much farther.
It should take at least six coats to properly sputter a reflector, and each coat should be very light. Allow fifteen minutes drying time between coats. It's more economical to sputter several reflectors at a time because you have to clear the nozzle of the spray can between each coat and this wastes a lot of the acrylic.
The first picture shows what the first coat of spray should look like. I sprayed a piece of glass to make it easier to see:
Cover your hand with a plastic bag or something similar and grasp the rear of the reflector, facing the front toward yourself. Hold the spray can the appropriate distance from the reflector and apply the first coat, rotating the reflector to insure even coverage. Spray for a fraction of a second at a time, look at the reflector, and spray more if you obviously missed some spots, but don't overdo it. Set the reflector down to dry and clean the nozzle by inverting the can and spraying until nothing but air comes out.
Here's a beamshot of a Mag with a sputtered reflector. It's the first beamshot I've ever taken and I clearly haven't gotten the technique down. In reality, the beam is white and even all the way across and the outer part is much closer to the hotspot in brightness. The beam resembles a surefire incan. The Mag-Num Star bulb is used here, for both its brightness and lack of artifacts.
After you've finished sputtering, allow the reflector to dry at least overnight before putting it in the light. I allow mine to dry for two weeks.
I'll be happy to answer any questions and listen to any suggestions for improving this technique.
