When it comes to nested products within a Production BOM, a separate nested Production Order is created for the nested product (e.g. Parent - Cupcake and Child - Frosting). However, in some cases, it will make more sense to produce the nested product in the same production process as the parent. 'Phantom BOMs' are used to explode components with assembly BOMs within a production order, without creating an assembly order - the BOM is 'phantom'.
A phantom represents a subassembly that is assembled only to be included in another assembly. It is a method for moving around a group of components under one item number. Phantom BOM can represent a product that is physically built, but not stocked, before being used in the next step or level of manufacturing. This can be used to add earlier production steps (Frosting) quickly and easily into multiple parent BOMs, while still keeping the child as part of the same production process. Phantom BOMs function like an assembly BOM with auto-assembly/disassembly enabled.
Phantom BOMs can also be used to auto-disassemble a component (e.g. package of flour) into the required quantity for production during the production process.
This is useful in three ways:
- It mirrors the logical process of production
- It enables a component (e.g. frosting) that is the same for multiple parent products to be quickly added to multiple production BOMs
- Easy conversion when product is bought with one unit of measure and needs to be converted to another. (e.g. a case of eggs, to a single egg)
This article assumes you have some familiarity with the DEAR production module, we recommend starting with the articles below.
NOTE: Access to the production module requires adding a subscription to the module to your DEAR Inventory paid plan. See Adding Trials of the POS, B2B, API, Automation and Production Modules to Paid Plans for more information.
- Getting the Production Module
- Production BOM
- Managing Production Orders
- Users will need the Inventory: Products & Families and Inventory: Product - Bill of Materials to enable/disable auto-assembly and add/edit assembly BOM for a product.
- Users will need the Production Bill of Materials to add/edit production BOM for a product.
Table of Contents
- Create a production BOM with a phantom BOM
- Example 1 - Nested product with auto-assembly
- Additional unit of measure and Phantom BOM
Create a production BOM with a phantom BOM
You will need to create an ASSEMBLY BOM for the nested product. In our example, our nested product (Frosting) has just two ingredients (Butter and Sugar). You can add production steps later.
Go to Inventory → Product → [select/create product]. Make sure your product has Bill of Materials: Assembly BOM.
Next, go to the Bill of Materials tab. Here, you can add the components of the intermediate product as a 'Phantom BOM'. You will need to check Auto-Assembly/Kit. Do not add any labour/services in this step, this will be added later when we create the production BOM for the parent product. Please see Bill of Materials (Assembly) if you need help creating an Assembly BOM.
Next, we create a production BOM for the parent product, where we will add the phantom BOM. Create a product and set Bill of Materials to Production BOM. Go to the Production BOM tab. In this example, we will create a production BOM for 50 units of chocolate cupcakes (our parent product). Please see Production BOM for more detailed instructions for populating production BOMs.
In step 1, we add an operation to create our phantom BOM product, frosting. We add Component: Frosting to the operation.
Next, we create another operations for making the cupcake - mixing the batter, and baking.
Finally, we bring the components together in the final step, which lists Chocolate Cupcake as a finished product.
As we have frosting saved as a separate component, this can now be added to every recipe that contains it - we could make strawberry cupcakes, vanilla cupcakes, lemon cupcakes, all using the same phantom BOM for frosting. When we create a production order for such a product, the auto-assembly will expand the phantom BOM to the bottom level of components.
Example 1 - Nested product with auto-assembly
Now we will create a production order for chocolate cupcakes to see how the phantom BOM explosion works in practice. When we go to Load BOM for the production order, we can see that Frosting has been exploded to its components, Butter and Sugar.
From here we can continue carrying out the production order as normal. Please see Managing Production Orders for more information on this process if you need help.
Additional unit of measure and phantom BOM
The Additional Units of Measure function allows more than one unit of measure to be specified for a product or service. For example, if the same bottle of wine is sold as an individual bottle, a case of 6, and a case of 12. Please see Additional units of measure for a full description of this functionality.
The Additional Units of Measure functionality can be used to automatically disassemble a case of items into singles, or do convert a product bought in lbs and used grams.
Adding additional units of measure to an SKU enables auto-assembly/disassembly. Receiving stock will automatically disassemble an SKU into the base unit. Likewise, when a SKU that is an additional unit of measure for another SKU is used in a production BOM, that SKU will be exploded to a multiple/fraction of the base unit when it used in a production order.
Example 1: We buy eggs in a pack of 50. Our base unit is a single egg, from the Additional Units of Measure tab on the inventory page for single egg, we can see that the 50-egg pack is a set of 50 eggs. Authorising stock received of a purchase of 50-egg packs automatically disassembles the packs into single eggs.
If single eggs are used in a production BOM, the production order will not disassemble further, as single eggs are the base unit.
Example 2: We buy cocoa powder in a kilogram packs, which is our base unit. In our production operation, we add cocoa powder in ounces from the Additional Units of Measure tab on the inventory page for cocoa powder (1kg). We can see that each oz is equivalent to 0.0283495 kg.
Authorising stock received of a purchase of 1 kg cocoa packs will not disassemble the pack, as the 1kg pack is the base unit. If a production BOM uses cocoa powder in ounces, the production order will explode this to show the conversion in grams.
As you can see, the production BOM specifies 7 oz of cocoa powder.
When loading the BOM for the production order, we can see that this has been converted to a fraction of a kg.