OK, I have now established proper metal content. The issue is more of an electrical code issue, and I'm hoping the wealth of knowledge of the usual suspects can help me out.
My basement shop needs more outlets. I had a nice new breaker panel installed a few years back, and it's time to add an outlet so I can run my mill without first unplugging the lathe.
The basement is finished, and has a "half wall" of wooden tongue & groove boards that ends about 10" below the bottom of the breaker panel box. The top of the wall is capped with a piece of 2x molding. The wall is built on 2x3 studs, and the plan is to mount the outlet box in the wall. I can run Romex once I'm in the wall, but I need to get from the breaker box to the top of the wall in a protected (and hopefully tidy) fashion.
My original notion was to bend up 1/2" conduit to bridge the gap. I can drill a hole in the top of the wall large enough to insert an inch or two of conduit. I can attach it to the breaker box with a standard clamp, going in through one of the bottom knockouts. I would then snake the Romex down through the conduit & into the wall.
The question is whether code requires any sort of bushing or clamp on either end of the conduit. Loose wires run in conduit do not require clamps. If the Romex was exposed where it came out of the conduit, a clamp would be required that fits on the end of conduit. It would take a much larger hole to fit the clamp down through the top of the wall, and the Romex is never exposed anywhere.
For my own peace of mind, it would be nice to have a clamp of some sort inside the breaker box to prevent anyone from accidentally yanking the Romex out. One option would be to slip one of the one-way plastic spring loaded NMSC clamps (the sort that usually go in a knockout) onto the cable just where it comes up out of the conduit fitting.
Given that previous licensed electricians ran Romex exposed and unprotected in other areas, I doubt anyone is ever going to get cranky about whatever I do. However, I try to stick to code whenever possible, and I'm at least curious as to exactly what the code might have to say about something like this (if anything). It's a bit too peculiar for any of my wiring books or the course I took years ago.