Steve Pope 110 Posted December 1, 2020 Report Share Posted December 1, 2020 I've often wondered if lead shot was used for ballast inside a swing keel and a vertical (when down) space down the face of the keel and a similar overall sized space available at the bottom of the keel to accommodate the shot, so that when the keel was raised the shot would flow to the now horizontal space that has become the lowest point, evening out the spread and keep everything on an even keel, so to speak. Quote Link to post Share on other sites
waikiore 74 Posted December 2, 2020 Report Share Posted December 2, 2020 That is one cool boat, just the sort of modern but practical design suited to NZ sailing. BNG and Fish 2 Quote Link to post Share on other sites
Steve 3 Posted December 2, 2020 Report Share Posted December 2, 2020 I backed her into the berth yesterday. 4.5 m at the stern so a little bit nervous. Not my boat and all that. Quote Link to post Share on other sites
Steve 3 Posted December 2, 2020 Report Share Posted December 2, 2020 10 hours ago, Island Time said: Centreboard designs often have a locking device - pin, hydraulic lock etc - to lock the board down. Hopefully well above the waaterline. The idea that it gives some additional safety in the event of a collision (grounding, floating or semi floating debris etc) would depend entirely on the individual design. If it was designed with that in mind, possibly. Some I've seen would compromise watertight integrity more easily than a fixed keel. If you think this is the case with one you may look at, I'd suggest you discuss it with the designer. I do like that boat though, and if I suddenly found lots of $$, it would be on the list for further consideration I believe they a sort of blow off valve which allows the keel to pivot backwards if grounded hard enough. Quote Link to post Share on other sites
Priscilla II 246 Posted December 2, 2020 Report Share Posted December 2, 2020 Engine needs to be running to lift keel. Quote Link to post Share on other sites
DrWatson 237 Posted December 2, 2020 Author Report Share Posted December 2, 2020 36 minutes ago, Steve said: backed her into the berth yesterday. Yeah was happy to hear that went without incident. Keel up I presume? Quote Link to post Share on other sites
DrWatson 237 Posted December 2, 2020 Author Report Share Posted December 2, 2020 51 minutes ago, Priscilla II said: Engine needs to be running to lift keel. Officially, yes, but that's because standard is AGM batteries. The keel pump draws up to 100A for about a minute. With LiFePO4 you don't really need to run the engine, but the keel pump motor runs through a relay controlled by the engine ignition. You can also manually pump the keel up or down - if you're enthusiastic. Quote Link to post Share on other sites
DrWatson 237 Posted December 2, 2020 Author Report Share Posted December 2, 2020 8 hours ago, Steve Pope said: I've often wondered if lead shot was used for ballast inside a swing keel and a vertical (when down) space down the face of the keel and a similar overall sized space available at the bottom of the keel to accommodate the shot, so that when the keel was raised the shot would flow to the now horizontal space that has become the lowest point, evening out the spread and keep everything on an even keel, so to speak. Interesting idea. But i think in a roll over or a knock down you'd rather have all your lead at the end of your board.... Quote Link to post Share on other sites
Steve 3 Posted December 2, 2020 Report Share Posted December 2, 2020 41 minutes ago, DrWatson said: Yeah was happy to hear that went without incident. Keel up I presume? Yes. And it was blowing. I think if you had the depth, keel down might be easier. But not that bad really. Quote Link to post Share on other sites
Island Time 786 Posted December 2, 2020 Report Share Posted December 2, 2020 57 minutes ago, Steve said: I believe they a sort of blow off valve which allows the keel to pivot backwards if grounded hard enough. Indeed, however the pressure induced by a solid keel impact, will create a shock, transmitted back thru the lift mechanism. In a severe impact it's likely to break the ram mounting points as the pressure cannot be released through a valve sufficiently quickly - fluid is not compressible etc. This issue may be designed in, with a "fuse" in the system to allow the keel to be pressed up as part of the shock absorption design... or not. Quote Link to post Share on other sites
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