BOM Levels organize components and subassemblies in a tree-like hierarchy to illustrate parent-child relationships, material requirements, and assembly sequences. The system functions as follows:
This format aligns with industry standards such as those from ASME or ISO for product data management.
Top-Level Assembly (Level 1): This represents the finished product or primary assembly (e.g., "ZZ Handguard Assembly" at level 1). It serves as the root of the hierarchy and typically has a quantity of 1 for the complete unit.
Sublevels (e.g., 1.1, 1.2): These denote direct subcomponents or subassemblies required to build the parent item above them. For instance:
Level 1.1 ("ZZ Handguard Barrel Nut") is a subassembly under the main assembly.
Level 1.2 ("ZZ Handguard Body") is another parallel subcomponent at the same depth.
Deeper Sublevels (e.g., 1.1.1, 1.1.2): Additional decimal points indicate further breakdown, such as raw materials, tools, or sub-subcomponents needed for the immediate parent. Examples from the table include:
Level 1.1.1 ("Carbide End Mill...") and 1.1.2 ("Aluminum 6061 - Rod..."), which are elements required to produce the Barrel Nut (level 1.1).
This nesting continues as needed, with each level inheriting the requirements of its parent.
Quantity and Units: Each item's quantity is specified relative to its parent (e.g., "ea" for each, "in" for inches). This ensures accurate calculation of total materials needed when scaling production. For example, if producing multiple top-level assemblies, quantities at lower levels are multiplied accordingly.
Purpose and Benefits: This leveled structure facilitates cost estimation, inventory management, procurement, and manufacturing planning by clearly delineating how parts fit together. It prevents duplication and enables software systems (e.g., ERP or CAD tools) to "explode" the BOM for total material needs or "implode" it for traceability.
To import BOMs into StartProto Directly, visit the Import Tools page and click on the tab that says Bill of Materials (BOM).
Or use the direct link here:
https://app.startproto.com/import-tools/bill-of-materials