Modeling a barbell equipment in Blender 3D

Step 0: Preparation
In this step we do a little research for dimensions and standards for the model to make the model look proportional. Several dimension standards that we’ll use were:
  •  Barbell bar length
  • Barbell bar diameter
  • Barbell disk diameter and thickness
 Barbell bar length standard was 1.2 meter to 2.2 meter. For this tutorial we will use 2.2 meter for the barbell bar length. Barbell bar diameter is between 25-51mm, for this tutorial we’ll use 50mm as the diameter of the bar. Next we’ll write down some standards for the barbell disk. Common diameter for  15Kg of barbell disk is roughly 360mm or 36cm, thickness is roughly 3cm and bore hole diameter is roughly 5cm.
After we get the reference dimension for our model, now we open blender and start modeling, but before we start modeling, we should set our scene to the proper unit. Because the dimension we gather were in metric system, we should adjust our blender scene into metric system. Click the scene panel in blender panels, then under Units subsection click the metric button to make our scene into a metric system.