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I recently had my Bavaria 34 lifted onto the hard at Foleux on the River Vilaine. As this is a new location for us I decided to watch the lifting operation and transporting of another Bavaria of similar size prior to our lift which the yard would be doing in my absence. The boat was well supported on the travel trailer, however I could not help but notice that there was a gap opened up between the aft end of the keel and the hull over a length of about 60mm. The gap obviously dissapeared when the boat was set down on its keel and ground supports.
This set me thinking; is there a problem with having a lead keel, which is probably much heavier than the standard iron keel. Is the hull strong enough to take the extra weight: Is the shape of the keel at its interface with the hull large enough, (its much more slender than the standard iron keel on my boat.); or was this a one off with the rear keel bolt not being tightened enough. I pointed the problem out to the yard and asked that they inform the owner.
I am drawing the attention of those who have a lead keel to my observations, as I feel they should be aware of what could be a serious problem.Alan
I doubt that the lead keel is much heavier than the standard cast iron keel, otherwise the boat would float lower in the water etc. I would expect it to be similar in weight but smaller in volume. Your comment that it is thinner may be part of the answer.
That said, clearly there should be no gap at the keel/hull joint so I would suspect a (potentially major?) problem with 2 or more keel bolts.
Roger
It is not necessarily a problem when there is separation of the keel from the hull especially at the extremities. My 1987 shallow fin Sadler 32 and the last few built had the 34 keel fitted. As it was longer it did not match the curvature of the hull. As long as the keel bolts are tight and water is not getting into them, then there should be no problem.
I cannot be sure but I believe Bavaria are sometimes using the same keel on different length boats. My Bavaria 37 spec says the deep keel is 2000kg but it is actually 2130kg. I have the Bavaria drawing. Is it possible that the Bavaria 37 (2007) and the new Bavaria 38 have the same keel?
I understand that the Bavaria cast iron keels are epoxied on as well as screwed on. Could it be that epoxy does not work on lead? My 37 cast iron keel after 2 years hard work including gales and knockdowns has no gaps or rust bleed marks.
Keith
The worrying part of the story above is that the gap opened up as the boat was lifted and closed again as the boat settled back on the keel. Clearly this means movement between keel and hull which can only mean trouble.
I am sure Saloma is glad the boat wasn’t his!
Roger
Hi Roger,
Looks like you have a good grasp of my observations. With regard to the weight of the lead keel, i would expect it to be heavier as its purpose is to increase the performance of the boat. It may be that the Bavaria lead keel started its life when they brought out the match racing boats. It would not need to set the boat much lower on her water line to displace a volume of water equal to the increased weight of the keel. The different keel weights will be shown in the original spec sheets. As the gap showing between the keel and the hull was so short and yet so wide at the back edge of the keel, I suspect that the hull had distorted over a localised area, just behind the last floor beam which takes the aft keel bolt. There is a sudden change in the ridgidity of the boats floor at this point and aft of that we have the weight of the engine. I have noticed with my B34 that when she is in a frame on the hard, if you do not put a prop close to the outboard leg to take this weight, the hull distorts at the rear props on the frame indicating the flexibility between the rear floor and the engine bay area.
I am guessing but would suspect it was down to a combination of the shape of the travel lift combined with the weight of the keel rather than bad design, even with a travelling boat hoist the stresses from the slings can deform the hull shape quite badly. Of course once back in the water the hull is fully supported by displacement and most gaps close right back up again.
Lifting can cause massive stresses on a hull and deck, I vaguely remember a few years ago a boat (Legend?) being lifted by a yard on the South coast which split along the hull/deck joint during the lift. I can’t even start to think about how you make the phone call to the owners when something like that happens.
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