If I've understood you proberly, try this...
Lets assume Description lines 1, 2 & 3 sit within excel boxes A2, B2 & C2.
In a spare column in row 2 type the following:-
=A2&" "&B2&" "&C2 and press enter
This will combine the descriptions into one cell, but as a formula. Drag the bottom right corner of the cell down to generate combined descriptions for all rows of your BOM.
Select all these new cells, Right click the selection, select 'COPY'
in another spare column in row2, right click again and select 'Paste option 'values'
This will now give you the combined descriptions as raw text for your BOM.
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Hope this makes sense.
