Sorry for keeping you waiting for so long. This is the second arc reactor I made. I did not completely copy the prop in themovie. I created some new designs.

Step 1: THE ELECTRIC CIRCUIT

This is the electric circuit plan of this arc reactor. I used SMDs as the light resources. The circuit is simple but the form is pretty complicated.

Step 2: LATERAL VIEW

The lateral view

Step 3: MAKE THE LIGHT RING!

This is the most essential and interesting part. The main material is plexigalss. I made all the parts with laser cutting. All the parts are made just as what I have designed.

After all the parts have been cut, i assembled them accoring to my plan. You can see how to do it from the image I post here.
I filled the space in the light ring with hot melt to make the light more soft.

While assembling the light ring, I fixed the SMDs on the bottom part of the ring base, and weld them.

Then I stick a plexiglass ring on this circuit. the dia of the ring =the dia of the circuit ring.
After all the above steps were completed, I cut the marks on the surface of the light ring for the exact location of the brass coil.
In the picture, you can clearly see the three-layer structure of the lignt ring.
paint the ring with clear blue.

Step 4: ADD THE COIL

This step is easy but you need more patience to do it.
First, circle the rubber tape on the preset marks on the light ring and wrap the copper plate in the rubber tape. Then circle the brass string on the tape, glue the brass string on the back side.

Step 5: MAKE THE CENTER COMPONENT

The center component is based on a round plexiglass plate. The plate is the remains of the previous cutting. The detailes are shown in my images.

Step 6: THE FINAL STEP AND FINAL DISPLAY

The final step is to assemble all the parts. Glue some plastic cubes on the interior side of the light ring to fix the center component.
This reactor is super thin, it is only less than 2CM including the cover.
Put the reactor into the round frame. The frame is a filter of the tea pot. Here is how I made the exterior metal ring: I took apart a thermometer and painted its cover silver to make it look like real metal.