NCEES PE Agricultural and Biological Engineering Engineering Drawing, Graphics & CAD: practice questions

1 · Orthographic projection · medium

The top view of a straight line AB measures 60 mm, and in the front view end B is 45 mm higher than end A. What are the true length of AB and its inclination θ to the HP?

1. 75 mm and 53.13°
2. 75 mm and 36.87°
3. 105 mm and 36.87°
4. 39.7 mm and 48.59°

2 · Dimensioning and tolerances · medium

On a shaft drawing, the overall length of 200 mm is shown in parentheses as (200), while the individual step lengths are dimensioned and toleranced. What does the parenthesised dimension mean?

1. It is the most critical dimension and must be inspected on every part
2. It is a theoretically exact dimension that locates a geometric tolerance zone
3. It is a dimension that may be changed by the machinist to suit the stock
4. An auxiliary dimension, for information only and not toleranced

3 · Dimensioning and tolerances · medium

A hole is 25.000–25.021 mm and its shaft is 24.980–24.993 mm. What are the maximum and minimum clearances?

1. 0.041 mm and 0.007 mm
2. 0.028 mm and 0.020 mm
3. 0.020 mm and 0.007 mm
4. 0.041 mm and 0.028 mm

4 · Dimensioning and tolerances · hard

A hole is 30.000–30.021 mm and a shaft is 30.002–30.015 mm. Classify the fit and give its extreme values.

1. Clearance; maximum clearance 0.019 mm, minimum clearance -0.002 mm
2. Transition; maximum clearance 0.006 mm, maximum interference 0.002 mm
3. Interference; maximum interference 0.015 mm, minimum interference 0.002 mm
4. Transition; maximum clearance 0.019 mm, maximum interference 0.015 mm

5 · Dimensioning and tolerances · medium

Why is the hole-basis system of fits more common than the shaft-basis system in general machine work?

1. Holes are made with fixed-size reamers and plug gauges, so fixing hole limits saves tooling
2. International standards forbid the shaft-basis system for parts above 10 mm diameter
3. The hole-basis system always gives interference fits, which are stronger in service
4. Shafts cannot be ground accurately, so their size must be allowed to vary over a wide range

6 · Isometric projection · hard

In an isometric drawing, an engineer measures a line parallel to one of the axes and finds it to be 40 mm, but the line is not drawn to the isometric scale. What true length does it represent?

1. 49.0 mm, because all isometric lines are foreshortened
2. It cannot be found, because no lines in an isometric drawing are measurable
3. 32.7 mm, because isometric drawings always use the isometric scale
4. 40 mm, because an isometric drawing uses true lengths along the axes

7 · Geometric dimensioning and tolerancing basics · medium

For a hole of size 10.0–10.2 mm with a position tolerance of ⌀0.1 at MMC, what is the virtual condition, i.e. the largest fixed pin that will always pass through?

1. 9.9 mm
2. 10.0 mm
3. 10.3 mm
4. 10.1 mm

8 · Geometric dimensioning and tolerancing basics · medium

Under the 3-2-1 principle, how many points of contact establish the primary, secondary and tertiary datums?

1. Three, three and three
2. One, two and three
3. Two, two and two
4. Three, two and one

9 · Fasteners and their drawing · hard

On a weld symbol, a small circle is drawn where the arrow line meets the reference line, together with a fillet triangle. What does it mean?

1. Spot weld of circular shape at the arrow point
2. Fillet weld all round the joint, as for a tube welded to a plate
3. Fillet weld made in the field rather than in the shop
4. Fillet weld to be finished flush by grinding

10 · Geometric dimensioning and tolerancing basics · hard

A datum feature symbol is attached to the large flat face on which a gearbox cover seats. Why is this face usually chosen as the primary datum?

1. It is the largest face, and GD&T always requires the largest face to be primary
2. It is the easiest face to paint, so it will be visible to inspectors
3. It is the face with the finest surface finish, which alone defines datums
4. It is the functional seating face that locates the part in assembly