Odd Flange PCD Calculator

Odd Flange PCD Calculator

Tip: If you can't find the exact center, measure from the left edge of one hole to the left edge of the next hole. This distance is the same as center-to-center.
Enter measurement to see PCD

The Math Behind It

This calculator determines the Pitch Circle Diameter (PCD) using the Chord Length Formula.

Because the holes are evenly spaced around a circle, the angle between any two adjacent holes is 360° / N (where N is the number of holes).

By measuring the straight-line distance between two holes (the Chord), we can use trigonometry to solve for the diameter:

PCD = Measurement / sin(180 / N)

Example: For a 5-hole flange with a 67.2mm measurement:

  1. Angle = 180 / 5 = 36°
  2. Sine of 36° ≈ 0.5878
  3. PCD = 67.2 / 0.5878 = 114.32mm
General Triangle Gusset Plate Generator

Gusset Plate Parameters (mm)

Gusset Shape (General Triangle)

The shape is defined by two adjacent side lengths (B and H) and the **included angle** ($\theta$) at the apex corner.

Applied to the $\theta$ corner.

Inner Cutout (Weight Reduction)

Distance from all 3 edges to the inner cutout triangle.

Engraving Option (Centered & Flat)

File Download Options

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The plate is centered at (0, 0). Dimensions are based on your input parameters (mm).

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