Calculate taper per foot, taper per inch, angle, and ratio from small and large diameters plus taper length in inches, mm, cm, or meters.

Taper Per Foot Calculator

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Taper Per Foot Formula

The following formula is used to calculate the taper per foot.

TPF = (LD - SD) / L

Variables:

  • TPF is the taper per foot (inches/foot)
  • LD is the large diameter (inches)
  • SD is the small diameter (inches)
  • L is the length over which the taper is measured (feet)

To calculate the taper per foot, subtract the small diameter from the large diameter and divide the result by the length over which the taper is measured.

What is Taper Per Foot?

Taper per foot is a measure of the gradual decrease in diameter of a conical shape or hole over a specified length. It is commonly used in engineering and manufacturing to describe the shape of tools, machine elements, or holes that are not cylindrical but taper in diameter from one end to the other. This measurement is crucial for ensuring that parts fit together correctly and function as intended.

How to Calculate Taper Per Foot?

The following steps outline how to calculate the Taper Per Foot.

  1. First, measure the large diameter (LD) at the wider end of the object or hole.
  2. Next, measure the small diameter (SD) at the narrower end.
  3. Then, measure the length (L) over which the taper occurs.
  4. Use the formula TPF = (LD - SD) / L to calculate the taper per foot.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem :

Use the following variables as an example problem to test your knowledge.

Large Diameter (LD) = 2 inches

Small Diameter (SD) = 1 inch

Length (L) = 4 feet