Possible to attach an external electrical box to an old work box?

Question

I have an old work box occupied by 6 ethernet keystones and the corresponding wall plate. I want to use a branching raceway to hide the ethernet patch cables coming out of the wall. But without other accessories, this will leave a few inches of exposed patch cable, because raceways generally attach to the sides of external boxes, not in-wall boxes. Is there an external box that can attach to my old work box, perhaps via the old work box’s wallplate mounting screw sockets?

I want the patch cables to remain plugged into the old work box’s keystones, run through the back of the external box (is there space to pass through terminated patch cables or must I cut a hole into the back of the external box?), out the side of the external box directly into the connected raceway. Is this possible?

Without an external box, this will leave a few inches of exposed patch cable (uglier) and creates another insect entry point via this open end of the raceway.

Without an old work box, having just an external box loses the flexibility to remove the external box (without redoing the punch-down termination for the wires) in case I find it cramps walking space. (And would this require wall repair for the hole left over from the old work box or would the external box’s back seal it?)

Drilling holes from the attic to route ethernet cables and separately move each keystone closer to its destination to shorten each patch cable run is out of the question.

Answer 1

Consider surface mount boxes. These are designed for line current, but are fine for low voltage. Just swap out your connectors and faceplates. They can mount over an existing old work box and have side access for raceways. Usually they require the same brand raceway to align properly.

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