Design with Parameters

What is Parametric Thinking?

Instead of:
> "The table is 100cm wide"

Think:
> "The table width is 2× the depth"
> "Legs are positioned 5cm from edges"

Why Parametric?

Easy Scaling

• Change ONE dimension
• Everything else adjusts proportionally

Consistency

• Parts always relate correctly
• No guessing for future modifications

Professional Practice

• CAD software is parametric
• Industry standard approach

Defining Your Parameters

Start by listing:

1. 1Primary dimension - Usually the biggest


2. 2Derived dimensions - Based on primary


3. 3Constants - Fixed values (material thickness, etc.)

Example: A Box

PRIMARY:
- Width = W

DERIVED:
- Depth = W × 0.6
- Height = W × 0.4
- Wall thickness = 0.1 (constant)

If W = 10:

• Depth = 6


• Height = 4


• Walls = 0.1

If W = 20:

• Depth = 12


• Height = 8


• Walls = 0.1

Practical Application

In our editor, think parametrically:

1. 1Decide primary dimension


2. 2Calculate others as ratios


3. 3Write them down


4. 4Use Properties panel to enter exact values

Common Ratios

Exercise Mindset

Before building anything:

1. 1Sketch on paper


2. 2Label dimensions with variables


3. 3Write the relationships


4. 4THEN open the editor