Mechanical Engineering Section C Machine Tool Practices Kibbe Section Dimensional Measurement Machinist Mainly Concerned With The

Machine Tool Practices, 11e (Kibbe)

Section C – Dimensional Measurement

1) A machinist is mainly concerned with the measurement of:

A) Length

B) Size

C) Diameter

D) Parts

2) Reliability in measurement is the ability to obtain the desired result to the degree of precision

required.

3) Accuracy refers to how finely the basic unit of length of a measuring instrument is divided.

4) A rule of thumb for choosing which measurement device to use is that the measuring

instrument should discriminate 5 times finer.

5) Calibration is the responsibility of the quality department and not the machinist.

6) Air gages are also known as pneumatic comparators.

7) Fixed gages can be used to check internal and external tapers.

8) 2.77 cm. is equal to:

A) .01074 inches

B) .1074 inches

C) 1.0704 inches

D) 107.4 inches

9) One inch is equal to 25.4 mm.

10) The measurement 0.0001 would be:

A) One hundredth

B) One ten-thousandth

C) One thousandth

D) One millionth

2

11) Knowing inches, to find cm. multiply inches by:

A) 25.4

B) 10

C) 2.54

D) .03937

12) A certain machined part is 1257 mm. long. Expressed in terms of meters, how long would

the part be:

A) 1.257 m.

B) 12570 m.

C) 125.7 m.

D) .1257 m.

13) Knowing mm., to find cm.:

A) Multiply by 10

B) Divide by 10

C) Divide by 100

D) Multiply by 100

14) .0625 inches is equal to how many mm.?

A) .625

B) 6.25

C) 1.58

D) .002

15) 17.27 cm is equal to how many inches?

A) 43.865 in.

B) .06799 in.

C) 172.7 in.

D) 6.799 in.

16) A cutting speed of 80 surface feet per minute is approximately how many cm. per minute?

A) 800

B) 960

C) 2438.4

D) 38

17) The correct name of the instrument a machinist commonly uses for measurement is the:

A) Ruler

B) Rule

C) Scale

D) A or B

18) The finest discrimination on a typical rule is 1/32 inch.

19) The finest discrimination on a typical fractional rule is usually:

A) 1/32 inch

B) 1/50 inch

C) 1/100 inch

D) 1/64 inch

20) When making a measurement with a rule the machinist must be careful not to introduce

________ error.

A) discrimination

B) parallax

C) parallel

D) angular

21) Decimal rules use the metric system of measurement.

22) Parallax error occurs when the rule is read from a point other than one directly above the

point of measurement.

23) The discrimination of a metric rule is usually 1/100 inch.

24) A machinist may often measure from the 1-inch marking on a rule to eliminate the problem

of wear.

25) A machinist should take more than one reading with a rule.

26) Accuracy refers to how finely a unit of length has been divided.

27) A vernier divides the units in which a measuring tool measures into smaller increments,

permitting high discrimination measurement.

28) The standard vernier caliper can make outside, inside, and depth measurements.

29) Vernier calipers are available in English but not metric types.

30) Mechanical dial instruments are direct reading and do not require interpretation like a

vernier.

31) The discrimination of a typical dial caliper is 0.010.

32) A digital caliper often has the capability to switch between English and metric

measurements.

33) What is the maximum discrimination of a standard inch (non-vernier) micrometer?

A) .0001 in.

B) .100 in.

C) .001 in.

D) .010 in.

34) The distance between the graduations on the sleeve of a micrometer is ________ of an inch.

A) .040 in.

B) .0001 in.

C) .025 in.

D) .001 in.

35) The part of the micrometer that carries the .001-inch graduations is the:

A) Carrier

B) Sleeve

C) Spindle

D) Thimble

36) How many threads per inch are on a micrometer spindle?

A) 10

B) 25

C) 40

D) 100

37) A combination micrometer is designed for dual system use in metric and inch measurement.

5

38) A two-inch micrometer can measure from:

A) 2 to 3 inches

B) 0 to 2 inches

C) 2 inches and up

D) 1 to 2 inches

39) The part of the micrometer which supports the anvil is called the:

A) Frame

B) Spindle

C) Brace

D) Support

40) The screw thread micrometer is specifically designed to measure the pitch diameter of a

screw thread.

41) The scale which permits reading a micrometer to .0001 inch is called the:

A) Milli

B) Vernier

C) Micro

D) Decimal

42) What part of a micrometer assures repeated equal measuring pressure?

A) Ratchet stop

B) Friction spindle

C) Spindle lock

D) A and C

43) In order to be certain of the dimension when measuring with a micrometer:

A) Show the mic to your instructor

B) Take at least two readings

C) Show the mic to a friend

D) Take at least one reading

44) When measuring a workpiece still hot from machining:

A) Cool off the workpiece

B) Warm up the micrometer

C) Do not let the anvil touch the work

D) Take a quick measurement

45) To measure a .3125 inch inside rounded corner, you would use a:

6

A) Inside corner gage

B) Radius gage

C) Fillet gage

D) Curvometer

46) A common comparison measuring system for holes ranging from approximately 5/16 to 6

inches would be a:

A) Binocular gage and scale

B) Dial bore gage

C) Small hole gage

D) Telescope gage and micrometer

47) A type of dial indicator that has general and versatile applications in machine setups is the:

A) Dial comparator indicator

B) Center gage indicator

C) Concentricity indicator

D) Back plunger dial indicator with mounting accessories

48) A precise square that has the ability to indicate the amount of deviation from true

perpendicularity is a:

A) Cylindrical square or micrometer square

B) Solid beam square

C) Precision beveled edge square

D) Combination square

49) You wish to check the outline of a form lathe cutter to determine whether it has been

properly ground. This could be done on:

A) A dial comparator

B) A profilometer

C) An optical comparator

D) A radius gage

50) A type of fixed precision square that provides a single line of contact with the workpiece is a:

A) Cylindrical square

B) Solid beam square

C) Precision beveled edge square

D) Micrometer square

51) You have just drilled and reamed a .250 inch diameter hole. In order to check the size, the

best tool would probably be a:

A) Dial bore gage

7

B) Dial test indicator

C) Small hole gage

D) Telescoping gage

52) Adjustable parallels could be used to measure:

A) The depth of a hole

B) The width of a slot

C) The height of a part

D) They are not used for measurement, they are used to adjust a piece to the correct height in a

vise.

53) A telescoping gage would be used to:

A) Check an internal hole size

B) Check the height of a piece of tubing

C) Check the depth of a groove

D) A and B are correct

54) When transferring height measurements using a precision height master micrometer, what

should always be used?

A) Dial comparator

B) Planer gage

C) Height gage scriber

D) Dial test indicator

55) A cylindrical square is used to measure:

A) The squareness of a part placed on a surface plate

B) The concentricity of an internal or external diameter

C) The squareness of an internal cylindrical bore

56) An AA set of gage blocks has a size tolerance of +/- .000002 inch. This set is:

A) An always accurate set

B) An inspection grade set

C) A shop grade set

D) A laboratory grade set

57) A conditioning stone is:

A) Used to bevel gage block edges

B) Used a s a gage block heat sink

C) A fine abrasive

D) Used sparingly for deburring gage blocks

8

Answer: D

58) As gage blocks are disassembled and replaced, they are:

A) Handled only with cloth or tissue

B) Thoroughly cleaned

C) Coated with preservative

D) All of the above

59) Wear blocks are used:

A) To gain additional measuring capacity with the gage block set

B) For machine setups involving cutting tools

C) To determine the accuracy of optical flats

D) To protect the gage blocks on the ends of the stack from damage by direct contact

60) Gage block wear may be caused by:

A) Improper handling

B) Burrs, dirt, and dust

C) Leaving blocks wrung for an extended periods of time

D) All of the above

61) A heat sink, in regards to gage blocks is:

A) Used to keep gage block from warping due to heat

B) A device to calibrate thermometers used to check gage block temperatures

C) Used to maintain the temperature in the gage lab at a constant level

D) Used to restore gage block temperature to the surrounding temperature

62) When assembling a gage block stack with assembly screws:

A) Tighten one and one-half turns to displace any air in the wringing interval

B) Gage blocks need not be wrung as the screw will hold them together

C) A torque screwdriver should be used

D) Use any available screwdriver

63) Gage blocks should be wrung if being stored for an extended period of time.

64) An acute angle is one that is less than 90 degrees.

65) An obtuse angle is one that is greater than 180 degrees.

66) There are 60 minutes in one degree.

9

Answer: TRUE

67) .5 degrees would be equal to 30 minutes.

68) A plate protractor can measure to within 5 minutes of accuracy.

69) There are always at least 2 acute angles in a right triangle.

70) If you add the angles in any triangle, they will total 180 degrees.

71) In the metric system, the unit of angular measure is the radian.

72) .5 degree would be equal to 30 seconds.

73) 1.5 degrees would be equal to:

A) 120 minutes

B) 90 seconds

C) 120 seconds

D) 90 minutes.

74) ISO 9001 is an international standard that specifies requirements for a quality management

system (QMS).

75) ISO 9001:2015 was designed for machine shops.

76) The ISO 9001 standard allows the individual enterprise to create their own system to meet

the ISO requirements.

77) The ISO 9001:2015 standard has 10 sections.

78) Calibration is one of the main ways in which an operator interacts with the ISO QMS.

79) A calibration log is a slang term for a device that machinists use to do quick checks to make

sure their micrometers are still accurate.

10

80) In most companies, machinists calibrate their own micrometers.

81) Costs of scrap include the following:

A) Material, machine time, machinist wages

B) Machine time, wages, maintenance

C) Material, energy, machinist wages, supervisor’s time

D) All of the above

82) There are two types of data: attribute and variable.

83) Attribute data tells us how good or how bad parts are.

84) No two things are exactly alike.

85) Variation is normal and all things vary.

86) Mean is just another term for average.

87) Range is a measure of variability.

88) Standard deviation is a measure of variability.

89) A bell curve can also be called a normal distribution.

90) There are normally ________ standard deviations in a bell curve.

A) 8

B) Standard deviations are not used in bell curves.

C) 6

D) 4

91) Capability is simple terms would be how close a tolerance a machine could hold on an

operation.

92) If the standard deviation for a process was found to be .001, which of the following is true?

A) 2/3 of parts could be made within .004

B) Almost all parts could be made withing .006

C) The bell curve would be .008 wide

D) The process is capable

93) Charts will show when a machine needs adjustment.

94) Charts make correct decisions 99.7% of the time.

95) Which of the following are charting rules for machine adjustment?

A) B and C are correct

B) Seven averages in a row are above the average

C) Seven ranges in a row are above the average

D) Charting is not done for adjustment of processes

96) When a chart shows a process within limits, it is assured that parts that meet the tolerance.

97) The correct use of a chart assures that a process is running at its best.

98) A chart measures all characteristics of a part.

99) A chart can be used to predict when a machine will need maintenance.

100) When we chart, we also are developing historical data on the processes or machines.