Re bedding Keels
The iron keels on a Westerly Centaur splay outwards so that the leeward keel is vertical and the windward keel is acting as a counter weight whilst healed over sailing. This gives a better sailing performance compared to other bilge keelers with vertical keels but can put great loads on the keel to hull joints. Older Centaurs and other bilge keel Westerly yachts have to be strengthened inside the keel stubs to prevent flexing which results in cracking. The great flexing and bending forces incurred whilst sailing and whilst grounding when the tide goes out will eventually cause to hull to keel joints to break down.
The iron keel is butt jointed to the moulded in GRP keel stub and held in place by six stainless steel studs with large washers and nuts. Sealant is applied to the contact surfaces to prevent water leaks but this sealant will eventually dry up and break down. Most manufacturers would give an effective life of the sealant as being around twenty years. You can make a tempary repair by applying sealant to the outside but it will not last. The only way is to remove the keel, scrape away the sealant and replace it. It is important to prime the cleaned surfaces before fresh sealant can be applied as otherwise it will not stick.
You will need to build a timber support around the keel to take its weight. You should then loosen the keel stud nuts and run a blade around the old sealant in the joint to help the keel and hull part. A crane will be needed to lift the vessel whilst you part the hull and keel with a large flat screwdriver, crow bar and other such brutal tools. It might take some shifting and you will need to watch out for your feet and hands. When eventually parted get the boatyard to block off the hull and make everything safe before you clean away the old sealant. Boatyards such as Retreat Boatyard on the Exe, Deacon's on the Hamble and Madge Marine in Chichester could do it all for you for around £1,000.00 per keel.
The sealant that would have originally been used on your Westerly is called Marineseal 033. It comes in two packs of putty which have to be carefully mixed together by hand. It is designed to remain flexible for at least twenty years and can be bought from Marine Mastics Ltd who are based in Waterlooville close to where Westerly's were built.
Sikoflex and other polyurethane sealants are also used to good effect.
Resources
Marineseal 033 available here:
Trade Sealants Ltd (Marine Mastics.com) Tel: 02392 251321
