What formula is used to calculate lead hexagon bar weight?

The formula is: Weight = (√3/2) × AF² × Length × Density. AF (across-flats) and length are converted to meters. The cross-section area of a regular hexagon expressed using across-flats is (√3/2) × AF², which equals approximately 0.8660 × AF². Multiplying by length gives volume (m³), and multiplying by lead density (11,340 kg/m³) gives weight in kilograms.

What is lead density and why is it so high?

Lead has a density of 11,340 kg/m³ (0.4097 lb/in³). This high density results from lead's large atomic mass (207.2 u) combined with its close-packed face-centered cubic crystal structure. Lead is about 4.2 times denser than aluminum and about 1.4 times denser than steel, which makes it valuable for radiation shielding, ballast, and sound-damping applications.

What is the across-flats (AF) dimension?

The across-flats (AF) dimension, also called "width across flats" or "wrench size," is the distance between two parallel flat sides of a hexagonal bar. It is the standard measurement used for hex stock, bolts, and nuts. The across-corners dimension is larger: AC = AF × (2/√3) ≈ AF × 1.1547.

Does this calculator support metric and imperial units?

Yes. The across-flats dimension can be entered in mm, cm, or inches. Bar length can be entered in meters, mm, feet, or inches. All values are converted to meters internally before the calculation.

How does lead hex bar weight compare to steel or aluminum?

Lead (11,340 kg/m³) is about 1.44 times heavier than carbon steel (~7,850 kg/m³) and about 4.2 times heavier than aluminum (2,700 kg/m³) for the same bar dimensions. A 30 mm AF × 1 m lead hex bar weighs roughly 8.8 kg, compared to about 6.1 kg for steel and about 2.1 kg for 6061 aluminum.

Can I calculate total weight for multiple bars?

Yes. Enter the number of bars in the Quantity field and the calculator will show both the per-bar weight and the total weight for the entire batch.

Lead Hexagon Bar Weight Calculator

Enter the across-flats size and bar length to instantly calculate lead hexagon bar weight in kg and lb, plus weight per meter.

Bar Dimensions

Across-Flats (AF)

Distance between two parallel flat sides (wrench size).

Bar Length

Quantity (bars)

Formula Reference

W = (√3/2) × AF² × L × 11,340

Where AF = across-flats (m), L = bar length (m), 11,340 = lead density (kg/m³), W = weight (kg). Cross-section area = (√3/2) × AF² ≈ 0.8660 × AF².

Enter dimensions on the left and click Calculate.

Lead vs. Common Metals — Density Comparison

Metal	kg/m³	lb/in³	vs Lead
Lead (Pb)	11,340	0.4097	1.00×
Tungsten (W)	19,300	0.6972	1.70×
Copper (Cu)	8,960	0.3237	0.79×
Carbon Steel	7,850	0.2836	0.69×
Stainless Steel 304	7,930	0.2864	0.70×
Brass (CuZn)	8,500	0.3070	0.75×
Aluminum 6061	2,700	0.0975	0.24×

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Summary

Enter the across-flats size and bar length to instantly calculate lead hexagon bar weight in kg and lb, plus weight per meter.

How it works

Enter the across-flats (AF) dimension of the hex bar in millimeters, inches, or centimeters.
Enter the bar length in meters, millimeters, feet, or inches.
Optionally enter a quantity for multiple bars.
The calculator applies W = (√3/2) × AF² × L × 11,340 and shows total weight in kg and lb plus weight per meter.
Click Copy to save the result to your clipboard.

Use cases

Calculating lead hex bar weight for radiation shielding fabrication.
Estimating ballast and counterweight mass for marine and aerospace applications.
Determining freight and shipping weight for lead hex stock orders.
Planning material requirements for battery terminal and cable lug manufacturing.
Verifying load limits when lifting or handling lead bar stock.
Cost estimation for lead hex bar purchases priced by weight.
Comparing lead vs. steel hex bar weight for ballast substitution.
Material planning for custom CNC-machined lead components.

Frequently Asked Questions

Last updated: 2026-09-19 · Reviewed by Nham Vu