Marine Group

  • Cardiff 02920 343459
  • Aberystwyth 01970 611422
  • Port Dinorwic 01248 671500/01248 670176
  • Burry Port 01554 835 691

Collision Repair

Back to Case Studies


The Jeanneau Sun Odyssey 42′ had a nasty collision with a submerged rock when she was travelling at high speed after finishing the Three Peaks race in Scotland. The vessel sustained damage to the main stiffening web around the keel, the hull laminate around the keel, the base of the keel and the rudder.

There was a large area of gel coat crazing in a ‘U’ shape around the back edge of the keel. The keel was removed so this area could properly inspected. The antifouling and gelcoat was ground away to expose the laminate in the areas of crazing.


There was no delamination this close to the gelcoat. Although the laminate at the back edge of the keel had cracked right through; this area took the brunt of the impact from the lever force of the keel hitting the rock. The area was faired in with polyester gelcoat.

Throughout the repair the boat was supported on the aft pads (positioned under a bulkhead) of the boat mover to keep the load off the damaged area thus not changing the shape.

The interior was striped down where necessary where the damage was assessed.

The interior was masked up and tented to keep the boat clean. Most of the damage to the stiffeners and delaminate was directly above and to the right of the keel. The damage laminate was ground away. The bonding flanges were cut away at the base of the stiffeners to allow further inspection of the hull laminate and to insure there was no further delamination under the stiffeners themselves. It was also essential to cut away the flanges to properly glass in the stiffeners.

100_1012The stiffener located at the trailing edge of the keel took the brunt of impact and as a result had sheared in two places. There was also some delamination under this stiffener. Therefore we cut out this stiffener and made a mould from it to fabricate a new one with the same laminate spec, size and shape.  The flanges were filleted with glass reinforced bonding filler and tabbed in with 6 layers of chopped strand mat and biaxial fibres. After that the floors in between the stiffeners were glassed in with 3 layers of 4” oversized fibreglass panels.