Measurement Tools Flashcards

A steel rule graduated in 1/64-inch increments is used to measure a part. What is the smallest increment that can be directly read?

Answer: 0.015625 inch

1/64 inch equals 0.015625 inch, which is the finest graduation on that rule.

When a feeler gauge blade drags with slight resistance when pulled from between two surfaces, this indicates the gap equals what?

Answer: The nominal thickness of that blade

A slight drag means the gap matches the nominal thickness of the feeler blade being used.

What is the function of the datum line on a vernier caliper scale?

Answer: It is the reference line from which both main scale and vernier readings are taken

The datum (index) line on the vernier scale aligns with the main scale to provide the reference for reading.

In pipe fitting, a pipe wrap or circumference tape is used primarily to:

Answer: Find the center for a cut by wrapping around the pipe circumference

A pipe wrap (wraparound) provides a straight reference line around a pipe's circumference to mark a square cut line.

A bore gauge is set using an outside micrometer before use. Why?

Answer: To set the bore gauge to a known dimension so it reads deviation from that size

Setting the bore gauge against a micrometer at the nominal size allows it to show plus or minus deviation from that dimension.

Which measurement technique uses a known standard block and a dial indicator to compare an unknown dimension?

Answer: Comparative (transfer) measurement

Comparative measurement involves zeroing an indicator on a known standard and reading the deviation on the unknown part.

What is the correct way to store a micrometer when not in use?

Answer: With a small gap between spindle and anvil, and in its case

Leaving a small gap prevents thermal expansion from damaging the measuring faces, and the case protects from dust and damage.