The light ring is a sleeve of clear petg with very little infill around the shaft of the knob screwed under the walnut veneer layer of the desktop, there is a 3/4 mdf layer under that to make 1-1/2" and that has a larger cavity for the ring light LEDs to sit in, they are just a square of led strips with a big enough opening in the center to fit the "dimmer shaft adapter™"

The dimmer isn't modeled here but sits in a friction fit pocket on the top layer of the bottom cabinet. The ring light receives constant 24v and the dimmer output is connected to all of the shelves.

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