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      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  

dcnblues

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About dcnblues

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    Member

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  • Location
    SF bay area
  • Interests
    Cats (Gunboat), tri's (Corsair 37)
  1. Gunboat 68

    I do have a question re hull shapes. The original 62 was a fairly straightforward tube, and shots of the wake at speed showed the water reuniting from a distinct shape of the hull's passage. The new hull looks more hydrodynamic, if that's the appropriate word. I assume the smoother the wake, the less drag and greater efficiency and greater speed benefit. The shape is designed in the computer, right? Can you talk about any of the improvements of the past, say, five years? Thank you.
  2. By the way, Chris White also wrote a book about catamaran design (it's basically the thoughts behind the design of his 55'), and it's a very informative and easy to read primer on cats. Highly recommended. He considers things which you won't find on newer designs, like skegs on the bottom of the hulls that reduce top speed, but allow you to beach the boat at high tide, and when the tide goes out, clean / scrape / paint the bottom, or do maintenance on props, etc. If one is on a budget, haul-outs can really look prohibitive depending on how diligent the owner wants to be. His book is an education, I promise. A taste can be found here: Atlantic Cat faq One the other end of the spectrum, do keep reading and doing research. The big boat shows are great places to ask questions and find what you're really looking for. But there are also youtube channels which are highly educational about life on board. I'm a fan of 'Sailing La Vagabonde,' and around episode 55 they get a state of the art Outremer 45: We're getting a Catamaran! You can find out a lot about costs, etc. (In another thread on this forum, it was generally agreed that one should budget about 10% of the cost of the boat to live and sail on it, per year. That's sobering.) I also like the strategy of doing some research, finding a boatyard you like, and buying a used / distressed boat for 1/10th the price of a new one, and then re-fitting it with your own specs, equipement, etc. Making it yours, and with new parts and paint it'll feel like a new boat. And, with decent project management, you'll be able to save some money to put toward the cruising budget.
  3. Caribbean 600

    Yeah, but aren't you running into a cube-squared law with the materials science that doesn't scale? When you're making boats the size and mass of dinosaurs, insect exoskeleton technology doesn't apply. *(not a materials engineer either, and happy to be corrected).
  4. Caribbean 600

    Drastically high boom / CE / CM too! What's that ratio called in naval architecture?
  5. Caribbean 600

    The physics just doesn't convince me. When some technology comes along that replaces stays on construction cranes, then maybe. Until then, the leverage of wires looks unbeatable to me. (Although the argument about aircraft spars is a good one. I'm guessing that aircraft speeds / drag over time cost too much fuel to keep wires as part of the design if you don't have to. Not such a big deal under sail).
  6. Gunboat 68

    Excellent! Thank you! Keep the sexy images coming (with that hull it's hard to go wrong, but the photographer does seem experienced at picking good angles)! Do remember that many of us are upgrading our computer monitors to higher resolutions, so give us these pics in as high a resolution as possible please! Many thanks!
  7. Gunboat 68

    Yes, thanks for the info, comments, answers, and pics. I hope your replacement posts here as well...
  8. Gunboat 68

    I WOULD MAKE IT WORK!!! GODDAMM is that a sexy image of the hull(s)! I am beyond obsessed. *edit: I would make it work with a mug of hot chocolate in my hand, Steely Dan cranking on the soundsystem, and my pulse as low and slow as a purring kitten. The boat is already hardwired for remote control, so why not have a remote in hand for joystick docking from the foredeck? (Come to think of it though, it's probable the throttle linkages are mechanical and not fly by wire, so I'd pay a couple of geeks to install supplemental remote control throttle servos in the engine bays, and program a nice handheld remote).
  9. Caribbean 600

    Need for fast and powerful release: Sawstop brake cartridge slo mo
  10. Caribbean 600

    Damm, I'd forgotten about that trifoiler. The speed of the tacks had to be measured in G forces. I had a long chat with Doug Kettering on the sand at Chrissy Field while he was testing a prototype (right before he sold it to Hobie). The trouble was the wands breaking, and it's not my memory that they had any mechanical linkage to the foils, or that the foils had flaps. The forward wands were just floating shock absorbers, essentially. The other downside is that you had to sit in the trifoiler like an ice boat, and it just didn't seem like sailing as you were too captive a passenger.
  11. Caribbean 600

    Have never owned a boat. Didn't really 'sail' a 60ft cat as much as power upwind for a 3000 mile delivery. However, have read a few heavy weather sailing manuals which a good number of 'experienced' racers don't seem to have, and their opinions sometimes don't seem all that informed to me.
  12. Caribbean 600

    Or even build it in to the boat design, and make it a triple system: Main sheet, main halyard, and jib sheet. Fast depowering, and easy enough to winch back into place. And you could put a shock-absorbing snubber on the pulley to keep it from banging up your boat when triggered / released! I knew I'd get my snubber in there!
  13. Caribbean 600

    My bad. The person who checked me out on the Sawstop table saw thought the brake cartridge was powered by a shotgun shell. It's actually a highly compressed spring which is held compressed by a wire. When activated, an electric charge melts the wire, and the spring is released. Obviously not practical for a jib clew release. I still sort of like the idea of a very fast way to blow away wind tension though, even if running a releasable bend in the sheet is more practical... Sawstop hot dog SawStop Inside Look Slow Motion
  14. Caribbean 600

    I don't think I've made myself clear. I like your concept of completely blowing both main and jib in the case of an overpowering gust. I like the idea of a reliable mechanical wand triggering a fast cam release on the main sheet, and it would be great to figure out a reliable option for the jib clew. But a line release isn't it. That line would then become the most dangerous potential snare on the boat. I can't imagine anyone wanting to rig something like that (how one would tack, just alone, seems a disqualifier). I think it would have to be something remote, though I agree that anything electronic would also have to have really good testing protocols for the user to feel confident. This thread has moved back to the topic of speed / how fast tipovers can happen, and that's a good thing, because I don't think even pro crews standing watch for hours and days on end can avoid becoming complacent. I'm big on ergonomics, by which I mean design which anticipates worse-case scenarios and adds to peace of mind. In million dollar boats, I'd consider this mandatory, and as I've previously said, I think racer mentality can be overconfident in having enough crew that any imagined scenario would be solved by throwing manpower at it. I agree 15 seconds seem like a slow estimate. My thing is a secondary concern once your system for the main sheet is applied. Any wall of wind potent enough to tip the boat would be potent enough to potentially (npi) cause some serious damage should the boom be 'blown' free. That properly rigged (and snubbed) preventer would, imho, be worth rigging if an expensive boat was in any kind of worrysome weather conditions. Any condition that would trigger the blowing of the main would also be a condition where the shrouds were also dealing with shock loads (granted less so the leeward shrouds) so not having several hundred pounds of boom slam into them like some cyclops' metal bat would be a plus. re 'bullshit,' just for the sake of argument: a) The V sections forward aren't even 10% of the waterline and spend half their time out of the water in swells, b ) the centerboards can be raised completely, and c) in many of these expensive new cats, so can the rudders. Again, this topic goes back to the racing mindset of 'pushing hard,' and it's my impression that in next year's race, should the conditions be identical and the race held again, you'd see pro skippers looking at the new information and gearing down as general awareness of capsize / mast failure risk has soaked into the community. That could possibly entail pulling some boards and even rudders up as a preventive measure, but on the other hand, maybe not so much. But we are talking about steep seas, and coming over the top of swells the boat is both exposed to more wind and has it's leeward hull the opposite of buried. I can see modern light round hulls sliding a bit with shortened dagger and rudder boards.
  15. Caribbean 600

    I'm going to second this request as this topic hasn't yet discussed the lateral resistance of newer generation daggerboards. We all take the benefits of multihulls as a given, but new designs seem to be bringing some negatives along with increased performance. New daggerboards are BIG. Enough so that the capsize risk seems to go up equivalently. Certainly as a factor of speed, but seemingly now even at low speed with a big enough slammed gust. Do new designs need a 'danger zone' polar? Which cross-graphs speed + gusts to recommend pulling certain percentages of the board(s) due to conditions? And what about just sailing with windward boards down in severe conditions? That's got to help.