I don't think you need a macro. You can do it with in-cell formulas and it
will be faster.
I would put the items on 2 different sheets. Master on one and Components
on another and use vlookup
If it MUST be on a single sheet, you could add a column for the Master and
Component codes and still do an in-cell formula to populate the cells based
on the Master and Component Codes (not particularly complicated, but
difficult to explain here.) I have an application that does something very
similar. I will share it if you are interested.

Glen

"Scott Wagner" wrote in message
...
I'm hoping to get some help with something that feels complex to me, that
may
or may not be for the guru's here.

In my worksheet I have products that, in some cases, have components as
well
as a master line item. There are two properties of the master line I need
to
apply to the component lines.

Property 1: The master line item has a master quantity that all the
component quantities must be multiplied by.

Property 2: The master line item sometimes has a marking that also must
appear on all component lines.

The master lines and component lines can be distingished from each other
easily. The master lines have a line item number (not quantity) in column
A.
It is sequenced line item 1, line item 2, line item 3, etc. The component
lines have nothing in column A.

Here is an example of what I have now:

ColA | ColB | ColC | ColD | ColE |
Line # | Qty | Description | Part # | Mark |
1 | 3 | MasterLine1 | ABC123 | H1 |
| 1 | Component1 | EFG123 | |
| 2 | Component2 | HIJ123 | |
2 | 2 | MasterLine2 | ABC123 | H2 |
| 1 | Component1 | EFG123 | |
| 2 | Component2 | HIJ123 | |


Here is what I want to end up with:
ColA | ColB | ColC | ColD | ColE |
Line # | Qty | Description | Part # | Mark |
1 | 3 | MasterLine1 | ABC123 | H1 |
| 3 | Component1 | EFG123 | H1 |
| 6 | Component2 | HIJ123 | H1 |
2 | 2 | MasterLine2 | ABC123 | H2 |
| 2 | Component1 | EFG123 | H2 |
| 4 | Component2 | HIJ123 | H2 |

Thanks in advance!

Scott