*2.3. Cost Estimation Tool Working Principle*

The cost calculation method can be divided into two main steps, one regarding the definition of the initial inputs, such as part's dimensions, client requirements, and needed material volume. The other step encompasses the definition of the part's complexity level and the calculation of the total operation times, based on the conjugation of all the defined parameters and the influence of the complexity level. These steps will be presented in the following Sections 2.2.1 and 2.2.2.

### 2.3.1. Step 1 of Cost Calculation

A flowchart was created to depict the cost estimation model. In Figure 5, the flowchart for the first cost calculation step can be observed.

**Figure 5.** Flow chart of the developed model, for the first cost calculation step.

The initial client's requirements are considered, as well as the part's dimensions. The latter is used to determine the amount (in kg) of raw material that will be used in the production process, with a higher volume of material being used for wider parts. With all this information defined, the machining strategy can also be determined, ending the first step of cost calculation.
