Roll Diameter to Footage Calculator
Here's a comprehensive table summarizing key information about roll diameter to footage conversion:
| Roll Diameter (inches) | Core Diameter (inches) | Material Thickness (inches) | Approximate Footage (feet) |
|---|---|---|---|
| 12 | 3 | 0.001 | 8,482 |
| 12 | 3 | 0.002 | 4,241 |
| 18 | 3 | 0.001 | 21,205 |
| 18 | 3 | 0.002 | 10,603 |
| 24 | 3 | 0.001 | 37,699 |
| 24 | 3 | 0.002 | 18,850 |
| 30 | 3 | 0.001 | 57,964 |
| 30 | 3 | 0.002 | 28,982 |
| 36 | 6 | 0.001 | 81,681 |
| 36 | 6 | 0.002 | 40,841 |
Additional important information:
- Formula: The basic formula for calculating footage is:
Footage = (π * (Roll Diameter² - Core Diameter²)) / (4 * Material Thickness * 12) - Factors affecting accuracy:
- Winding tension
- Air gaps between layers
- Material compression
- Manufacturing tolerances
- Common core diameters:
- 3 inches
- 6 inches
- 8 inches (for larger industrial rolls)
- Material considerations:
- Paper: typically 0.002 to 0.010 inches thick
- Plastic film: can be as thin as 0.00048 inches
- Fabric: varies widely, from 0.004 to 0.020 inches or more
- Industry applications:
- Paper manufacturing
- Plastic film production
- Textile industry
- Packaging materials
- Adhesive tapes
- Conversion factors:
- 1 foot = 12 inches
- 1 yard = 3 feet = 36 inches
- Tips for accurate measurement:
- Use a calibrated caliper for precise diameter measurements
- Measure material thickness at multiple points for consistency
- Consider using a footage counter for direct measurement when possible
- Environmental factors:
- Temperature and humidity can affect material thickness
- Store rolls in controlled environments for consistency
- Safety considerations:
- Large rolls can be heavy; use appropriate lifting equipment
- Secure rolls to prevent unintended unraveling
Remember that while this table and information provide a good starting point, actual footage may vary due to the factors mentioned above. For critical applications, it's always best to verify calculations with direct measurements or consult with the material manufacturer for specific roll footage information.