1. Tolerance Calculations
Basic Shaft System

2. Tolerances
The basic shaft system of calculating tolerances is based on using standard shafting. Holes are then machined to any size desired. The minimum shaft size is taken as the basic size and tolerances are applied to both the shaft and hole.
Given the following specifications find the limit dimension for both the shaft and the hole using the “Basic Shaft System”
Nominal size
2.0000
Fit
RC8

3. Tolerances
Using the American National Standard Running and Sliding Fits table cross reference the nominal hole size (2.00) with the Standard Limits values (RC8)

4. Tolerances
Using the American National Standard Running and Sliding Fits table cross reference the nominal hole size (2.00) with the Standard Limits values (RC8)
Hole
Shaft
+4.5
-6.0 -0
-9.0

5. Tolerances
Convert the numbers to thousands by moving the decimal point 3 places to the left or dividing the numbers 1000.
Hole
Shaft

6. Tolerances Reverse the values and the sign of the hole and shaft. Hole
Hole
Shaft

7. Tolerances
Add or subtract the values to the nominal size to find the upper and lower limits dimensions of the hole and shaft
Hole Shaft
The limits dimension for the hole diameter is ( ) and the limits dimension for the shaft is ( ).
2.0000
2.0060
2.0090
2.0000
1.9955

8. Tolerances Minimum Allowance
The minimum allowance is the difference between the smallest hole and the largest shaft.
Minimum Allowance
Smallest Hole
Largest Shaft
Minimum Allowance

9. Tolerances Maximum Allowance
The maximum allowance is the difference between the largest hole and the smallest shaft.
Maximum Allowance
Largest Hole
Smallest Shaft
Maximum Allowance

10. Tolerances
Limits of Clearance