Furniture plans: Creating parts without merging?

Piecey

I'm trying to create a model of a furniture piece and using Onshape to keep track of a parts/cut list.

When I go to extrude a part which shares a face with another part, there is no option to NOT merge the two. How do I avoid this issue?
Perhaps its because I'm using it incorrectly but what would be the best approach to modeling this?

For example, I want to make a simple box with lid with 5 parts (4 sides and bottom) for the main box and another 5 for the lid.

Is it best to draw the completed shape then make the cut to separate the lid and box?
OR
Is it best practice to create each part individually then mate them in an assembly?
If the latter, how do I create drawings so each part stays separate, and I can calculate for example, dimensions of each piece for cost calculation?

nick_papageorge073

Within the extrude command, select "new" rather than "add". That will make each extrude a separate part.

For the second part of your question, it's usually best to model closely related parts together in one part studio. A box and lid would certainly qualify. You would still assemble the parts in an assembly. The assy offers different functionality, especially BOM tables, which are of course paramount for costing.

nick_papageorge073

Here is one way to make a parametric box with lid. A million ways to do this though. Note only the unique parts are modeled. Then in the assembly, they are duplicated.

https://cad.onshape.com/documents/e6b81d9c8c72b3b7af15e202/v/553ff117569e1b59547f8906/e/dba33fe9daedb87693302291?bomType=structured&renderMode=0&rightPanel=BOMPanel&uiState=643cb9a74eaa6208deca7f25