How to Specify an RC3 Fit for a Hole and Shaft?

We Want to Specify an RC3 Class Fit for the Illustrated Hole and Shaft. What is the Minimum Allowable Diameter of the Hole if its Basic Size is 1.25 Inches?

In order to specify an RC3 fit for the illustrated hole and shaft, we need to determine the minimum allowable diameter of the hole. The basic size of the hole for an RC3 fit is 1.25 + 0.0015 = 1.2515 inches.

How to Specify an RC3 Fit?

To specify an RC3 fit for the illustrated hole and shaft, we need to determine the minimum allowable diameter of the hole.

First, we need to know the limits of the hole and shaft sizes for an RC3 fit. According to ANSI B4.1 standard for fits and tolerances, the basic size of the shaft is 1.25 inches and the tolerance class is H11. The basic size of the hole for an RC3 fit is determined by adding a certain amount of allowance to the basic size of the shaft. The allowance is calculated based on the fit type, the shaft tolerance class, and the hole tolerance class. For an RC3 fit, the allowance is 0.0015 inches.

Therefore, the basic size of the hole for an RC3 fit is 1.25 + 0.0015 = 1.2515 inches. This is the minimum allowable diameter of the hole for the specified fit.

Read more about RC3 here.

How to specify an RC3 fit for a hole and shaft?

To specify an RC3 fit for a hole and shaft, the minimum allowable diameter of the hole can be calculated by adding an allowance of 0.0015 inches to the basic size of the shaft, which in this case is 1.25 inches. The resulting diameter is 1.2515 inches.