An aluminium mast inspection should look beyond obvious dents. Corrosion around fittings, cracking at local load points, movement of fasteners and damage at the heel or spreader roots can all provide useful evidence about the condition of the spar.
High-value inspection areas
Mast heel and step
Check drainage, corrosion, distortion, fasteners and the contact surfaces at the heel or mast step.
Spreader roots
Look for movement, cracking, distortion, corrosion and elongated holes around brackets and attachment fasteners.
Gooseneck and vang
These fittings see repeated cyclic loading. Check fasteners, bracket edges, local distortion and signs of movement.
Stay attachments
Inspect T-terminal slots, tangs, eyes and other rigging attachment areas for cracking, corrosion and local deformation.
Masthead
Check sheaves, pins, headbox fittings, halyard wear points and forestay/backstay attachments.
Fasteners and mixed metals
Pay particular attention where stainless fasteners and aluminium are in contact, especially where coatings or sealants have broken down.
Corrosion: what to look for
Aluminium spars can develop local corrosion where water and salt are trapped around fittings, fasteners and interfaces between dissimilar metals. White or powdery deposits, lifting coatings and pitting are warning signs that deserve closer inspection.
Surface staining alone does not tell you how much material has been lost. Where corrosion is significant, remove the fitting only if it can be done safely and the area can be properly assessed.
Cracks and local deformation
Cracks often occur around stress concentrations: fitting edges, fastener holes, cut-outs and attachment points. Good lighting and a clean surface are important. If there is doubt about a structural crack, stop treating the issue as cosmetic and seek professional assessment.
Inspection with the mast down
When to stop and ask for advice
- Visible cracking in the extrusion.
- Deep or widespread pitting.
- Significant dents, buckling or permanent distortion.
- Movement around spreader or stay fittings.
- Fastener holes that have elongated or torn.
- Uncertain previous repairs.
Found something you are unsure about?
Send clear overview and close-up photographs, plus the mast ID and yacht details where possible. We can help identify what information is needed for the next step.