Common assembly mistakes

Tower incidents are rarely exotic. Investigations find the same short list of assembly mistakes again and again — which is good news, because a known list is a checkable list.

The classic errors

• Missing braces. "It felt solid without the last two" — until the racking load arrives. The manual's diagram is a load path; every brace on it is structural, including the ones that look decorative. Diagonals especially.
• Castors unlocked or legs unclipped. Four brakes take twenty seconds. A tower that walks while someone is on it is a fall from height with extra steps.
• Stabilisers skipped or set wrong. The configuration table says what your height needs — fitting them late or not at all is the most common cause of overturning outdoors.
• Climbing the outside. Towers are climbed inside, through the trapdoors. Outside climbing pulls the tower over — it is the one rule even non-users know, and it is still broken weekly.
• Standing on an unguarded platform during the build. This is exactly what the 3T and AGR methods exist to prevent. If someone is stood on a deck with no guardrails, the method has already failed.
• Wrong or mixed components. A borrowed platform from another system, a fence post where a brace should be — a certified tower becomes an uncertified guess. See compatible parts.
• Ignoring ground and weather. Soft ground swallows one leg; wind above the manual's limit turns platforms into sails. Both are check-before-build items, not endure-during-work items.

The two-minute defence

Before first climb, walk one lap: diagram in hand, count braces, push each guardrail, toe the brakes, sight the stabilisers, look up for cables. Two minutes, every build, every alteration. It catches every mistake on this list — which is the entire point of the pre-use check.