---
title: "Assembly BOMs"
slug: "bc-assembly-boms"
description: "Optimize your project with assembly BOMs: create, modify, and manage components for efficient assembly orders and planning lines."
updated: 2026-06-25T09:59:10Z
published: 2026-06-25T09:59:10Z
canonical: "docs.staedean.com/bc-assembly-boms"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.staedean.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Assembly BOMs

Make assembly BOMs project-specific in the budget line as well as the planning line. These lines show the following actions:

- **Create/Reset Project Assembly BOM**: copies the item's assembly BOM to the project assembly component list. You can modify this list by adding or deleting components or changing quantities. When a modified components list already exists, the following warning appears: "Project assembly components already exist. Do you want to update/delete the components?" Selecting **Yes** deletes the project assembly component list and copies the assembly BOM from the item again.
- **Show Project Assembly BOM**: shows the current project assembly BOM. When no project assembly BOM has been created, the standard assembly BOM appears.
- **Delete Project Assembly BOM**: deletes the current project assembly BOM.

You can use assembly BOMs in two ways:

- As components for an assembly order.
- As a set of components.

### Steps - Use assembly BOM as components for an assembly order

To assemble an item planning line:

1. Complete and release the item planning line. Make sure the **Replenishment System** field is set to **Assembly** and the assembly BOM is not expanded as components.
2. Click **Replenishment** > **Order Planning** to open the **Order Planning** page.
3. If the selected project planning line is not visible on the **Order Planning** page, use the **Calculate** action to recalculate the project demand.
4. Use the **Make Order** action to create the assembly order. By selecting the project number, you can select **Active Order** and create all supply orders for the project, or select **Active Line** for a specific supply order.
5. A message appears: "The lines were successfully transferred to assembly order(s)."
6. From the project planning line, open the assembly order by clicking the **Transferred** field, or use the **Show Replenishment Document** action from the **Replenishment** menu.

### Steps - Use assembly BOM as a set of components

To expand the assembly BOM as a set of individual budget or planning lines:

1. In the budget line or planning line, use the **Components** > **Expand Assembly BOM** action to expand the assembly BOM as budget or planning lines.
2. The **Quantity Per** field on the parent item is set to 0. You can use this field to change the quantity of the complete set. The previous quantity is saved in the hidden **Quantity Before BOM Explosion** field.
3. Once expanded, you can modify or delete components. To add components, select the parent item, click **Add Components** in the ribbon, and select an item number in the pop-up.

## Related

- [Assembly hours setup](/bc-assembly-hours-setup.md)
- [Resource planning for assembly](/bc-resource-planning-for-assembly.md)