- Measure the structure as built, never off the architectural plan.
- Agree the datum and the module before anything is cut.
- Decide the coating before the welding sequence, not after.
Architectural metalwork is unforgiving in a way that back-of-house fabrication is not. A bench that is 3mm out of square disappears. A 4.2 metre run of feature framing on a Pitt Street shopfront or a Melbourne laneway that is 3mm out accumulates into a visible taper by the far end, and there is nowhere to hide it because the whole point of the element is that people look at it.
The plan is a proposal, the building is a fact
We do not fabricate architectural work from architectural drawings alone, not in Sydney and not anywhere in Australia. Slabs are poured out of level, blockwork bows, columns land off grid, and the ceiling grid is set out from a different datum than the floor. Every one of those is normal, and every one of them will be blamed on the fabricator if the framing is cut to the drawing.
- Measure the opening as built at three heights and three widths, and record the worst case.
- Establish one datum with a laser and mark it on the structure in a place that will survive other trades.
- Photograph every service, penetration and obstruction inside the zone.
- Confirm what is fixing into what, and whether the substrate can actually take the load.
Where the tolerance goes
You cannot remove tolerance, you can only decide where it accumulates. On a run of vertical fins the eye reads the gaps between them, not the absolute dimension of the run, so we hold the module and take the variation in the two end panels against the wall. On a shopfront that has to align with adjacent tenancies the opposite is true. That decision belongs on the shop drawings, agreed in writing, before steel is cut.
Coating decides the sequence
Powder coating has to happen after all welding, because you cannot weld through a coating and touch-up never matches. That means the assembly has to be broken into pieces that fit the coater's oven and that can be bolted together on site without a weld. Hot dip galvanising adds its own constraints: parts distort in the bath, vent holes are needed on hollow sections, and the finish thickens edges. Deciding the coating late is how a job ends up welded on site and painted with a brush.
| Finish | Suits | Watch for |
|---|---|---|
| Powder coat | Interior and sheltered feature work | No site welding after coating |
| Hot dip galvanise | Exposed structural, wet areas | Distortion, vent holes, edge build |
| Stainless 316, brushed | Coastal and exposed architectural | Grain direction, tea staining |
| Two-pack paint | Repairs and colour matching | Site conditions and cure time |
Architectural steel is not harder to make than kitchen steel. It is harder to set out, and set-out happens before anyone turns a machine on.