Before choosing a treatment, it is important to know the stage of corrosion. A wrong diagnosis = a wrong treatment. Here's how to assess the condition of your metal at a glance.
The 4 Stages of Rust in a Table
| Stage | Appearance | Metal Condition | What to do? |
|---|---|---|---|
| 1. Superficial | Light orange/brown film | Intact | Light brushing + GALVACYL® |
| 2. Established | Patches, rough surface | Surface healthy | Vigorous brushing + treatment |
| 3. Advanced | Deep rust, pitted surface | Loss of material | Remove, consolidate, protect |
| 4. Perforating | Perforations, holes | Compromised | Replace the part |
Stage 1 — Superficial Oxidation
Appearance: slight orange or brownish discoloration, sometimes just a light film of rust.
Metal condition: intact, solid, no loss of material.
Urgency: low — but it's the best time to intervene.
Treatment: light brushing is sufficient before applying GALVACYL®.
Stage 2 — Established Rust
Appearance: visible rust patches, rough surface, beginning of flaking.
Metal condition: slightly weakened on the surface, but structurally sound.
Urgency: medium — treat before it progresses.
Treatment: vigorous mechanical brushing, then full treatment.
Stage 3 — Advanced Corrosion
Appearance: deep rust, metal flaking off in patches, pitted surface.
Metal condition: visible loss of material, reduced mechanical strength.
Urgency: high.
Treatment: remove all loose material, consolidate if possible, then protect.
Stage 4 — Perforating Corrosion
Appearance: visible perforations, holes in the metal.
Metal condition: structurally compromised.
Treatment: replacement of the part is necessary — protection alone is no longer enough.
The Golden Rule
The earlier you intervene, the less costly and complex it is. A Stage 1 treated with GALVACYL® in 30 minutes can prevent a complete replacement costing several hundred euros.
FAQ
Can treatment be applied to visible rust?
Yes, up to stage 2, after good brushing. See: can you paint over rust?
My gate is at stage 2-3, what should I do?
It can often be saved without dismantling it: how to repair a rusty gate.
In Summary
Identifying the correct stage means choosing the right treatment. Up to stage 2, GALVACYL® cold galvanizing stops corrosion in minutes. To learn more, consult our complete guide to protecting your steel from rust.
