How to combine two different BOM in drawing .
Check the attached screen shot.
BOM's are mostly generated from an Assembly file, create an assembly and insert both sub-assemblies that you show and you will have what you want
What John said. After inserting the BOM for the combined assembly in your drawing you can delete the drawing view you used to generate it since after being inserted into a drawing BOM's are linked to the assembly itself, not the drawing view.
One thing that John and Glenn didn't mention is that when you create the BOM for the new master assembly you will want to either make it a "Parts Only" BOM or in the configurations properties for each subassembly you will want to set the Child Component display to "Promote". If you need any clarification on either of those options just say so and I can give more detailed instructions.
Your assembly file can be made up with different configurations of the components used. Insert each configuration of the assembly into the drawing and when you select the view assign a BOM to that view and it will be the correct BOM for that configuration. Do the same for each view with the different configuration.
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