Round Bar Size Calculator

It uses the rectangle length and width along with machining allowance to estimate the correct round stock size.

Formula:

Diameter = √(Length² + Width²) + (2 × Allowance)

Choosing the correct bar size ensures enough material is available for machining and prevents undersized stock issues.

Example:

For a rectangular feature:

Length = 1.50 inches

Width = 1.00 inches

Allowance = 0.020 inches

Diameter ≈ √(1.50² + 1.00²) + (2 × 0.020)

Diameter ≈ 1.803 + 0.040 = 1.843 inches

Recommended Stock Size ≈ 1.875 inches

When to use this calculator:

Use this calculator to determine the minimum round bar stock required before machining rectangular or square features.

Machining tip:

Always select the next standard bar size above the calculated diameter to ensure proper cleanup and avoid running out of material during machining.

Use these related machining calculators to improve accuracy and save time: