Combination Set Components Explained

A combination set is a versatile measuring and marking tool. It typically includes several heads that can be attached to a graduated rule.

Standard Combination Set Parts

• Square head: Used for setting and checking 90-degree and 45-degree angles.
• Centre head: Used with the square head and rule to find the center of round stock or shafts.
• Protractor head: Used to measure or set angles accurately.

Identifying the Outlier

The question asks which item is NOT a part of a standard combination set. Let's examine the options:

• Centre head: As noted above, this is a standard component used for finding centers.
• Protractor head: This is also a standard component for angle measurement.
• Square head: This is the primary head for marking right angles and 45-degree angles.
• Slip gauge: Slip gauges are precision blocks used as standards for length measurement and calibration. They are not typically included as part of a combination set, although they are crucial tools in metrology.

Conclusion

Based on the functions and typical composition of a combination set, the slip gauge is the item that does not belong.