One more information about keels: the ones that seem to be the most reliable in racing boats are the ones in Carbon (not the ballast obviously
). There is not probably any boat that has reunited more experience with top keels than the Open 60's. The Open 60's are not only used on the Vendee Globe but also used extensively in many other races, inclusive another duo circumnavigation.
One of the men that knows more about the race and Open 60's is the two times winner and mentor of this year winner, Michel Desjoeaux and when he says that the Carbon is the most resistant material, well...he knows what he is talking about.
"There is no miracle solution to choose a keel observes Michel Desjoyeaux, we move between price, reliability and performance. "his firm Mer Forte worked for two boats on the Vendée Globe: Savéol (Samantha Davies) and Macif (François Gabart). "For Samantha Davies we told her that the better option would be solid steel, recalls Michel Desjoyeaux.
She had no money for a carbon keel and then a solid steel one seemed to us the most reliable. "a not massive steel keel fabricated with a grid is lighter than solid steel and can be made with the adequate profile but the welding of the different sheet is very delicate. "In the industrial lambda landscape, welding is 50% as strong as the solid sheet, explains Michel Desjoyeaux. But if special care is taken to welding, you reach 75/80%.
"So for Macif, the mechanically welded keel was carried out by a specialized company Quimperlé with a welder and a welding specialist. This piece then requested an very careful maintenance because the welding "cook" the metal and makes it prone to rust. "At sea, the keels are close to the surface, immersed in saline oxygen-rich environment. This deteriorates the weldings and the steel tends to rust. "
It seems that it is the more resistant material but not what allows for a lesser weight
He says that the Carbon is better (more resistant) but the boat that he prepared for the winner had a "Mecano" keel made of sheets of welded steel while the boat that come in 2th had a solid steel keel. The hulls were identical and I wonder if that difference in weight had to do with the marginal better performance of Macif.
Jean-Pierre, one of the three two that lost the keel had a solid steel as well as Alex while Stamm and wavre had carbon keels.
Riou had, like the winner a mechanically welded steel.
For keels I am referring to the blade.
It seems that Carbon on the blade of keels will be a technology that we will see more often in the future.