Workshop Practice and Practical Skills
This domain tests the operations you perform at the bench and on site: marking, sawing, planing, jointing, bricklaying, bar bending and plumbing, plus the measuring instruments and their least counts.
Operations and checks
- Carpentry: mark with a try square and marking gauge, saw on the waste side of the line to preserve the kerf, plane with the grain, and cut joints such as halving, mortise-and-tenon and dovetail.
- Masonry: soak bricks before laying, keep joints about 10 mm, check every course with spirit level and plumb, and stretch a line between pins for alignment.
- Bar bending: cutting length includes hook and bend allowances and excludes cover; hooks and bends follow the bar bending schedule.
- Plumbing: cut PVC square, clean and apply solvent cement, and lay drainage pipes to the specified fall.
- Measuring instruments: vernier calliper least count 0.02 mm, micrometer 0.01 mm, steel rule 0.5 mm.
Worked example
A door frame of clear size 2.1 m high and 0.9 m wide, timber section 75 mm × 100 mm, has two verticals and one top member. Total length = 2 × 2.1 + 0.9 = 5.1 m, before adding horns. Volume = 5.1 × 0.075 × 0.100 = 0.03825 m³, that is 0.038 m³ of timber, which converts to cost directly at the schedule rate per m³.
Traps that cost marks
Cutting on the line and losing the size to saw kerf; measuring from a damaged end instead of a fresh face; laying dry bricks that suck water from the mortar; joints thicker than 10 mm weakening the masonry; quoting a vernier least count as 0.01 mm when that belongs to a micrometer.