Precision comes from process, not equipment. A team with a hacksaw, a drill press and a good marking routine can outbuild a team with a CNC and no plan.
Core operationsLink to this section
- Mark from a single datum edge, never chain measurements.
- Centre-punch every hole before drilling.
- Drill aluminium with a pilot, then step up in 2mm increments.
- Deburr both sides of every hole — burrs cause misalignment and cuts.
TappingLink to this section
| Thread | Tap drill | Clearance drill |
|---|---|---|
| M3 | 2.5 mm | 3.2 mm |
| M4 | 3.3 mm | 4.3 mm |
| M5 | 4.2 mm | 5.3 mm |
| #8-32 | #29 (3.5 mm) | #19 (4.2 mm) |