I've started to design a simple saw bench. A cross beam with 4 legs, which Carpenters use, and develop the complex geometry using planes as a teaching aid. Most of the teaching aids I've seen are a complete design bringing components together to be assembled. Here I've design the assembly to match the area and support required but now I'm now stuck as I cannot seem to copy the "leg" to develop the assembly and drawings as would normally be the case.
How should I go about this? I began by creating the "cut-outs" and to prove the design filled the cut-out with a short leg as shown. It would appear that I cannot easily separate these now to "reverse engineer" the design. Are the any examples of copying and separating geometry like this?