Try these eight original questions in order and write your working before opening each answer. They cover the four lessons in sections and spatial reasoning.
Questions
1. On a top view, a plane line has arrows pointing upward on the page and is labelled A-A. Which part of the object is imagined removed?
Answer
The part on the arrow side, above the line on the page. You then look at the cut face in the direction the arrows point.
2. A block is 80 mm wide and 25 mm high with a through hole of diameter 30 mm, centred. A plane cuts through the hole’s centre across the width. Give the width of each hatched strip.
Answer
(80 − 30) ÷ 2 = 25 mm each. The 30 mm gap is left clear, and each strip is 25 mm high.
3. A student hatches the inside of a slot in a section view. State the error.
Answer
A slot is empty space, and hatching marks cut material only. The slot must be left clear, with its walls drawn as visible lines.
4. Two strips of one cut part are hatched at 45° and 135°. What is wrong?
Answer
One part cut by one plane must have one hatching angle and one spacing. Different angles suggest two separate parts.
5. A block is 60 mm wide and 40 mm deep, with a vertical hole of diameter 16 mm centred 20 mm from the front. A plane is placed 30 mm from the front. Does it cut the hole?
Answer
The hole spans 20 − 8 = 12 to 20 + 8 = 28 mm from the front. The plane at 30 mm lies 2 mm beyond the far edge, so it misses the hole. The cut face is fully hatched.
6. A plate is 50 mm high. A blind hole of diameter 12 mm goes 35 mm down from the top, and a plane cuts through its centre. How thick is the solid below the hole in the section?
Answer
50 − 35 = 15 mm. This hatched layer under the hole shows that the hole does not go through.
7. A cylinder of diameter 40 mm and height 30 mm has a coaxial bore of diameter 24 mm. A plane passes through the axis. Give each hatched strip width, and say what the section shows about the bore.
Answer
(40 − 24) ÷ 2 = 8 mm each side, 30 mm high. The clear 24 mm gap shows the bore runs the full height of 30 mm, so it is a through bore.
8. A block has hole M (through, centred 20 mm from the front) and hole N (through, centred 50 mm from the front), each of diameter 10 mm. A single plane is placed 20 mm from the front. Explain what the section reveals and does not reveal.
Answer
It passes through the centre of M, showing a through hole with a clear 10 mm gap over the full height. N spans 45 to 55 mm from the front, so the plane misses it by 25 mm. The section does not show N, which needs another plane at 50 mm.
If you got these wrong
- Questions 1 and 5: reread interpreting a stated cutting plane.
- Questions 2, 6 and 7: reread representing the visible section of a solid.
- Question 8: reread which internal features a section reveals.
- Questions 3 and 4: reread comparing an inconsistent section with its correction.
Next, study how solids unfold in surface development concepts.
If you want a teacher to set fresh questions and check your reasoning, see online one-to-one Engineering Drawing tuition.