Is there a crop command to nuke everything outside a drawn planar shape?

I have a grid 1cm I place in background of plans for client to check printout of e.g. pdf.
Its A0 size, so wishing to make an A4 one, placing an A4 rectangle over the grid, I need a quick way of trimming away grid beyond the A4 rectangle.
Tried grouping grid then trim but it insists on me picking each and every line beyond the A4 rectangle, it doesnt see selection of group as such, acts as if grid ungrouped.


Hi Steve -Try - Split the objects with the boundary curve, then SelBoundary then Invert and Delete - just be careful before you delete that you have the right selection, it looks like the boundary selection can be a little iffy for objects that have endpoints right on the boundary.
Also, SelVolumeBox, snapping to the corners of your rectangle.


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