COLVIC SAILOR 29 FIN KEEL QUESTION

[CRASHED AGAIN]

Hi All,
Would anyone know what metal was used in the Fin Keel of a 1980s Colvic Sailor 29, cast iron or lead? And how were they formed, poured molten into the GRP moulded keel or free cast and just bolted on to the hull? Fin Keel, not Bilge Keels.

 

[CRASHED AGAIN]

We will have a spare mast and a set of sails available from a Fin Keeled Colvic Sailor 29. Phone: 07976 218972.

 

[Bajansailor]

Your question might be more effective if it was posted in the PBO Forum rather than here.

Maybe the @Moderator can move it perhaps?

 

[LittleSister]

I have no specific knowledge of the Colvic 29, but I presume from the wording of your question they have an encapsulated keel. As Colvic were a relatively budget brand, I would be very surprised if the ballast were lead, rather than steel.

Typical encapsulated keel construction was very small pieces of steel (punchings) mixed with resin and placed inside the keel moulding before settings to form a solid lump. IIRC Colvics were commonly sold for home completion, with the workmanship and materials of the home completed parts, which would typically include the ballast, being very varied - with some very poor, a lot middling, and a few better than yard completed boats.

With that (very common) form of construction it is essential to both build it and maintain it to prevent water ingress into the steel ballast, either though un-repaired damage to the external GRP of the keel, or inadequate original sealing of the top of the ballast in the bilges. It is rarely a problem, but if water does get into the ballast, the steel rusts and expands, and can 'blow' outward the GRP keel, ultimately threatening its integrity. Can usually be relatively easily solved if you catch it early enough, but prevention far better.

 

[Praxinoscope]

A friend had a Seawych, with an encapsulated keel, which had water ingress, foolishly he ignored the problem and the whole keel eventually cracked open and split the hull at the same time,

 

[LittleSister]

A friend had a Seawych, with an encapsulated keel, which had water ingress, foolishly he ignored the problem and the whole keel eventually cracked open and split the hull at the same time,

That's a terrible shame, as if he'd addressed it early, it would have been an easy fix.

99% plus of encapsulated keels have no problems at all. It is a fine method of construction, provided it's constructed properly, and any damage to the GRP of the keel is promptly repaired.

I imagine that the bulk of the small percentage of encapsulated keel that have problems result from -
- bilge keelers regularly grounded without protective shoes on the bottom of the keels, and consequent wear ignored;
- home builders failing to seal the top of the ballast internally;
- failure to repair GRP damage from severe keel impacts.

 

[Wansworth]

A friend had a Seawych, with an encapsulated keel, which had water ingress, foolishly he ignored the problem and the whole keel eventually cracked open and split the hull at the same time,

Saw that the new owner cut the side off the keel and stacked in new ballast and glassed it over

 

[Keith 66]

Steel punchings set in resin was commonly used by most builders of budget yachts, Thames marine used it on the Snapdragon range, A lot would depend on which crew built the boat, some just chucking the punchings in adding resin & stirring it about, this tends to leave big air voids in the steel. The other aspect is that usually a slow catalyst to resin mix was used due to the big mass & exotherm, If too much catalyst was used styrene build up could also cause pressure build up.
A cautionary tale, a couple of ex Thames marine guys i used to work with got a job to cure the bulging keel of a snapdragon, one of them cut into the bulge with a diamond cutter & hit a styrene filled void, the sparks from the grinder wheel hitting the punchings ignited the styrene which was under huge pressure. He caught the jet of flame in the face & spent a week in the burns unit with serious flash burns.

 

[samfieldhouse]

I have the original drawings for the Colvic Sailor 26 and 29, of interest?

 

[LittleSister]

The OP hasn't checked in since the day he posted his questions!