4. (a) Explain the following terms:
(i) pinning
Pinning refers to the clogging of the file teeth with pins, which are material shavings. These pins cause the file to lose its cutting ability and can scratch the workpiece.
OR
Pinning occurs when metal pieces, known as pins, get stuck within the teeth of the file. The pins then reduce the effectiveness of the file and also scratch the workpiece.
(ii) curing
Curing of concrete is the provision of adequate moisture, temperature, and time to allow the concrete to achieve the desired properties for its intended use
OR
Curing is the process of maintaining satisfactory moisture content and temperature in freshly cast concrete for a definite period of time immediately following placement
(b) (i) Make a freehand sketch of an outside callipers

(ii) State one use of the outside callipers
Outside callipers are used to measure thicknesses or outside diameters of objects.
(c) State one use of the following measuring tools:
(i) steel rule
• Marking out on a metal plate
• Taking measurements
(ii) tape measure
• Taking measurements
• Setting out
• marking out
(d) State two methods each for maintaining the tools stated in (c) above.
(i) maintaining steel rule
• Keep it clean and dry
• Use it for its intended purpose only
• Avoid bending it
• Avoid scratching its surface
(ii) maintaining tape measure
• After using, roll back into its case
• Keep in a tool box
• Keep it clean and dry
• Use it for its intended purpose only
(e) Copy and complete the table below
Process | One tool used |
(i) Plumbing a wall | Plumb line Spirit level |
(ii) Checking corners of a wall | Builder’s square |
(iii) Measuring aggregates | Gauge box |
(iv) Checking courses of a wall | Gauge rod |
(v) Picking and spreading mortar | Trowel |
(vi) Mixing mortar | Shovel spade |