Odoo natively supports over or under production when the Bill of Materials has a flexible "yield" or, in other words, there is a variable quantity produced by each Manufacturing Order.

Consider three Manufacturing Orders for Cookies.

Ideally we can make 25 cookies (1) from each "recipe" - represented by the Bill of Materials:

Let's follow example MO's where we make

• 25 using the quantity of ingredients on the BoM
• 24 using the quantity of ingredients on the BoM
• 26 using more ingredients than on the BoM  

Note: we need flexible consumption on the Bill of Materials so we can adjust the quantity of our components (raw materials).

A Manufacturing Order for 25:

When the Quantity produced is equal to the Quantity on the Bill of Materials, in our case 25 (1) simply click PRODUCE ALL, and we will see the following adjustments to Inventory:

A Manufacturing Order for 24 (less):

Here we have to adjust (1) the Quantity being produced from 25 to 24 and (3) the quantity of raw materials / components being used since it is different than what we "should" be using (2).

When we click PRODUCE, we will see two popup dialogs:

We confirm we are using more raw materials that we "should" for 24 cookies - we are using what we should use for 25 cookies.

We confirm we are making LESS and will NOT be making the extra cookie!

We will see the following adjustments to Inventory, with our finished quantity of 24 (1) and the same amount of raw materials as our previous MO:

A Manufacturing Order for 26 (more):

Here we have to adjust (1) the Quantity being produced from 25 to 26and (3) the quantity of raw materials / components being used since we ended up using more butter and more chocolate chips.

When we click PRODUCE, we will see the following popup dialog:

We just need to confirm we are using more.

We will see the following adjustments to Inventory, with the planned finished quantity of 24 (1) plus the additional quantity (2), the quantity of ingredients on the BoM (3) and our extra butter and chocolate chips (4):

The Bill of Materials can therefore be created base on the "ideal" amount of consumption and the "ideal" yield but we can adjust the "actual" quantities consumed and produced for each individual Manufacturing Order.