When a weldment feature is added to a part, the software creates two default configurations: a parent configuration, Default<As Machined>, and a derived configuration, Default<As Welded>.
You create the model in the <As Machined> configuration, and include all machined features. Then, if you want to show the part as it appears before the machining operations are performed, you use the <As Welded> configuration and suppress the machined features.
For example, for the following part:
- In the <As Machined> configuration, you create the structural members, extrude the plate, add weld beads, and add the holes in the plate and structural members.
- Then, in the <As Welded> configuration, you suppress the hole features.
On a per document basis, you can suppress the automatic creation of the
[As Welded] configuration. Before adding weldments to a new document, click
Options 
(Standard toolbar). On the
Weldments page of
Document Properties, clear
Create derived configuration.