7.3.7 Marking Out

Question 1

What materials are rules made of?

Answer 1

Rules are made of tempered carbon steel or satin-finished stainless steel.

Question 2

What are the standard lengths of rules?

Answer 2

Rules usually come in standard lengths of six inches (152.4 mm) and 12 inches (304.8 mm).

Question 3

What unit of measure is most used in aviation?

Answer 3

The unit of measure most used in aviation is the ‘inch’.

Question 4

What scales do most rules have?

Answer 4

Most rules have a graduated scale in both the fraction and metric system.

Question 5

What is a rule used for?

Answer 5

A rule can be used either as a measuring tool or as a straight edge.

Question 6

How are fractional scale divisions for an inch determined?

Answer 6

The fractional scale divisions for an inch are found by dividing the inch into equal parts.

Question 7

What are the fractional divisions of an inch?

Answer 7

Halves (1/2), Quarters (1/4), Eighths (1/8), Sixteenths (1/16), Thirty-seconds (1/32), Sixty-fourths (1/64).

Question 8

How can fractions of an inch be expressed?

Answer 8

Fractions of an inch can be expressed in decimals, called decimal equivalents of an inch.

Question 9

What is a flexible steel tape used for?

Answer 9

The flexible steel tape is a very useful instrument for taking measurements up to several feet.

Question 10

What feature does a flexible steel tape have?

Answer 10

The steel tape is equipped with a hook on one end to hold onto a corner or ledge.

Question 11

What is the purpose of the hook on a steel tape?

Answer 11

The hook allows the rule to be used by one individual and accounts for its thickness in calculations.

Question 12

What measurements do most steel tapes have?

Answer 12

Most steel tapes have a graduated scale in imperial and metric measurements.

Question 13

What is the role of a steel rule and tape measure in an Aircraft Engineer’s toolkit?

Answer 13

They are used as a guide and are not subject to calibration.

Question 14

When must a ruler be calibrated?

Answer 14

If a ruler is being used to accurately measure an item for inspection or modification, then a calibrated one must be used.

Question 15

What is a combination set used for?

Answer 15

The combination set can be used for the same purposes as an ordinary tri-square.

Question 16

What features does a combination set have?

Answer 16

It has a sliding head, a level, and a scriber.

Question 17

What is the purpose of the spirit level in the square head of a combination set?

Answer 17

It makes it convenient to square a piece of material and check if it is plumb or level.

Question 18

What can the combination of square head and rule be used for?

Answer 18

It can be used as a marking gauge, to scribe lines at a 45° angle, as a depth gauge, or as a height gauge.

Question 19

What is the Engineers Square used for?

Answer 19

It is used for marking out on metal.

Question 20

What are common sizes of Engineers Squares?

Answer 20

Common sizes usually available range from 3” to 12”.

Question 21

What standards do Engineer Squares conform to?

Answer 21

They conform to UK and European Standard, BS 939 and DIN 875 respectively.

Question 22

What is the purpose of a scriber?

Answer 22

The scriber is used to scribe or mark lines on metal surfaces.

Question 23

What are the characteristics of a scriber?

Answer 23

The scriber is made of tool steel, 10 to 100 cm long, with two needle pointed ends.

Question 24

What is the use of dividers?

Answer 24

Dividers are used for scribing arcs and circles, measuring between points, and transferring dimensions.

Question 25

What are the two common types of callipers?

Answer 25

Inside and Outside callipers.

Question 26

What are radius gauges used for?

Answer 26

Radius gauges are used to measure either the inside or the outside radii.

Question 27

What is a feeler gauge set made of?

Answer 27

Feeler gauge sets are made up of several thin steel leaves that fold into a handle.

Question 28

What technique is practiced with a feeler gauge?

Answer 28

The ‘Go, No-Go’ technique.

Question 29

What are punches classified by?

Answer 29

Punches are classified according to their shape of head.

Question 30

What is a prick punch used for?

Answer 30

A prick punch is used when marking up a piece of metal to show where holes are to be drilled.

Question 31

What is a centre punch used for?

Answer 31

A centre punch is used to make indentations in metal to prevent ‘wander’ when starting to drill a hole.

Question 32

What is an automatic centre punch?

Answer 32

An automatic centre punch incorporates an adjustable spring-loaded trip mechanism.

Question 33

What is the purpose of a starting (taper) punch?

Answer 33

It is used to start when driving out a bolt or pin.

Question 34

What are pin punches used for?

Answer 34

Pin punches are used for driving out rivets and are sized by the diameter of the face.

Question 35

What is a roll pin punch used for?

Answer 35

Roll pin punches are used for the removal of roll pins.

Question 36

What materials can be used for punches to minimize damage?

Answer 36

Beryllium-Copper and Brass Punches are used where damage may occur.

Question 37

What maintenance is required for punches?

Answer 37

The punch end must be ground back to its original shape if it becomes burred.