Which part of the metal shield are you talking about?
The half round one was left on the property when I purchased the place. Its actually one of them things that hold dirt back away from a basement window.
The heated part of the shop is 30x30 and insulated. With the stove on one side, and no airflow, the other side gets cold. So I found a use for that half-round piece and set a box fan behind it so it blows the warm air out .
It worked really well at getting the heat moving. Then I added the green polebarn siding later to further improve on the design so that all of the air from the box fan gets directed under and around the stove.
Not sure if you can see the fan in the pics, but its behind the green metal siding and on a downward angle. It works really well:thumbsup: