Step 1: Choosing a Size
To cut it I used a band saw. I cut it a little wider (a FRACTION!) so it fit snug.
Step 2: Depth
Take wire cutters, cut power cord to desired length, strip away cover, strip away wire coating leaving 3/8" of bare wire showing, twist ends of cord wire clockwise with wire at light (white to white and black to black), twist cap on (seen here in orange) clockwise, give both wires a gentle tug to ensure security, plug in, LET THERE BE LIGHT!
From there I held the plexi over the light to find the approximate depth, table to top. I found that 5" is pretty comfortable lighting.
Step 3: Building the Box
I routed the edges deep enough to accommodate 2 panes of plexi for sturdiness. The picture shows the extra space I left for the second pane. Being as the router blade is round, I had to go at the corners with a chisel to square the corners. For the first time ever chiseling wood I thought I did pretty darn good.
To compensate for the lip I needed to rest the plexi on and my jointing, I added a 1/4" to the length and width. I went with a little flair and "dove-tail" jointed the walls of the box. This actually turned out better than I thought, except that I made it too wide(measure twice!!) so I wasn't able to use a second pane of plexi but will soon.
I wouldn't recommend doing it this way I just felt like a challenge. This can simply be done with screws, staples or nails, butting the ends together and slapping it together.
Step 4: Finishing Touches
I spray painted the inside of the box and bottom panel white. The bottom panel is just a piece of 1/4" plywood cut to size.
After I painted the panel drilled small holes for only 2 of the mounting screws and attached it. I just rummaged around till I found screws that fit.
I drilled a hole in the side of the box(outside-in) to feed the wire BEFORE I painted. This way when it splintered it could easily be fixed and painted over.
Plug it in, slap the plexi on, and Voila! A super awesome and affordable light table for just under $40(price may vary per person, i had a lot of free stuff around)!
You might be able to tell from the picture but since I couldn't use the other pane of plexi I didn't have the full "frosted" effect. In my humble opinion this maybe be beneficial because adding a diffusion element lessens the amount of light the picture receives. The only diffusion on there is the protective plastic on the plexi. It may be less attractive but way more functional.
Step 5: Product in Use
I'm also using it as a laptop table.