Instructables

Step 3: Frosting and Diffusing

To get the nice 'glowing' effect with the LED box, we need to have a 'frosted' look on the box and need LED's that are diffused.

I only could get my hands on water clear acrylic sheets and water clear LED's. For all those who have the same, continue with this step.

If you already have frosted acrylic (opal acrylic) and diffused LED's, then you can continue with step 4.

1. Get the fine sandpaper (400) and place it on a table, with the sanding side up. Get a plate and rub it over the sandpaper in a circular motion. If one side is frosted enough, turn the plate over and do the same with that side.
Now you'll have a nice frosted looking effect we need (photo 1 and 2 to see the difference).


2. Do the same with the LED's. Sand the LED's until they get the nice diffused look (Photo 3,4 and 5).

Photo 5 shows you 1 diffused and 1 water clear LED hooked on a 3v button cell.

I've found heavy duty scotch-brite pads(the green ones with the yellow sponge on one side) to work really well at frosting strips of LEDs (or LEDs mounted to circuit boards) they are soft enough that they don't break the LED leads, but abrasive enough that they scratch the surface of the led as well if not better than an emery cloth...
How would I go about frosting RGB LED strips? Or, should I just frost the plexi glass and set the strips inside? I'm using some audio software to sync my music from my laptop to the LED's to change color based on the output frequencies which is why I am tending to use a strip rather than individual lights. Thanks! :)
liong4 years ago
hello guys i wanna ask some questions.
how is the diameter 1st and 2nd hole for the Acrylic plastic glass ?
Greg Fou4 years ago
Man,I haven't started making it yet,but I still can't understand how you used the sandpaper...(that's because I haven't heard that before)is there any similar kind of glass which I can buy from the internet or something? very cool tut anyway...Good work :)
Greg Fou he took the sand paper and rubed the plexiglass with it so the scratches gave a frosted look.
DarkSelenia4 years ago
I don't know how it is around the world, but at least here in Finland we have frosting 'paint' in spray cans, and right now I can't remember how much it costs, but it was not expencive at all.
That's a good idea. I've seen the frosting paint in the US, too. I think it's labeled as a glass etching faux finish. 
I think it was something like that in here too, nice stuff, I just love it ;)
Sanding the dome flat/flatter on a tightly focused LED, like those pictured, will produce a wide beam and more diffusion.