Step 1: Supplies
The hardest part was figuring out what light to use - initially we thought we would just drop a wire through the pipe and make our own light, but due to cost and the fact that we have never fused/made lights from scratch, we just found lights that we took apart.
Remember to make sure all the parts fit together - we found that we could pop off the clip to the light and easily screw in the light to the 3/8" coupling. Hence, everything is based off this diameter, but if you want a thicker pipe, you can easily find couplings that go from one size to another.
And we used gas pipe (black) because it was slightly cheaper - the steel costs the most.
Technically, here is what we used, and again, the diameter was 3/8".
4x- 4" pipe
4x - flange
4x - 90 degree elbow
4x - 3/8" going to 3/8" coupling
4x- screw and washer (short enough that it will not go through the wood shelf)
4x - lights
Step 2: Spray Paint
Step 3: Putting It Together
Flange --> 90 degree elbow --> 4" pipe --> coupling --> light.
Then just screw it into the shelf - we only used one screw and found it was sturdy enough. Since we wanted to use the screws we had on hand (but were too small for the hole) we used a washer to add width to the screw.
The wires are kept organized with some twist ties to the pipe.
Then all you have to do is plug it in, pour some scotch, and admire your highlighted artwork!
PS - What we are planning to add are dimmers to give more of an effect. I believe those can be easily and cheaply found at Ikea.