# Chapter 12: Tolerancing ```Chapter 12
Tolerancing
1.
What is the purpose of Tolerancing?
2.
When does the maximum clearance occur?
3.
When does the minimum clearance occur?
4.
Define “Nominal Size”.
5.
What is the “Basic Hole System”?
6.
What is the “Basic Shaft System”?
7.
Why is the basic-hole system more common than the basic-shaft system?
8.
Which method is the preferred method of expressing tolerances?
9.
What do the two numbers of a limit dimension mean?
10. List five classes of fit.
11. What does the tem “Hole-Basis system of preferred fits” mean in reference to the metric system of
tolerances and fits?
12. What does the tem “Shaft-Basis system of preferred fits” mean in reference to the metric system of
tolerances and fits?
13. How is the tolerance grade specified in the metric system of tolerances and fits?
Tolerance Chart Assignment…Determine the limit dimensions for the hole and shaft for each of the
basic sizes identified. The values for .375, RC5 have been provided as an example.
Basic
Size
0.375
0.750
1.875
Name:
RC 5
Hole
Shaft
.3759
.3740
.3750
.3734
LC 1
Hole
LT4
Shaft
Hole
FN1
Shaft
Hole
Shaft
```