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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.  

JimC

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About JimC

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  • Birthday January 1

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    http://www.devboats.co.uk
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  • Location
    South East England
  • Interests
    Dinghies, especially box rule classes.

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  1. I know exactly what you mean, but worth doing the sums for how much weight though if you just add foam over the existing skin. Its not as if you need to make a full strength outer skin, it only needs to be strong enough to cope with handling, and the core can be low density too: its not as if its structural. And, after all, if after a bit of tuning you end up with a shape that meets all your requirements, you can always get the angle grinder out and cut off and replace the modified parts of your hulls to reduce the weight, and you can regard the Mk1 foam additions as being low cost prototyping.
  2. Its a bit of a piece of string question. I've done a bit of this sort of hacking on smaller boats, and some shells are relatively floppy and can be persuaded to change shape fairly readily, whilst others are rock solid and won't move. Have you considered whether your desired aims could be met by addition rather than subtraction? Could you just glue foam onto the existing skin fore and aft (if you want a reversible change) and add a new skin (which could be relatively lightweight as non structural) or even remove the outer skin and add the foam and then a new full spec outer skin? I've altered dinghies by both of those methods, and it has the huge advantage that none of the internal framing and structural components are changed, so the job is a whole lot easier and cheaper. If you leave the original skin untouched OK you pay a weight penalty, but it has the enormous advantage that if, after a season or two, you decide the change was for the worse, all that's required is to remove the new skin in the areas you wish to change again, reshape and reskin. There are no structural considerations at all.
  3. The one thing I would bet is that if the prop guard is intended to be fitted over a standard prop then it will be lacking. I am quite convinced that a good implementation will have a prop that is specifically designed to work with a specific design of propguard.
  4. And the message they got was "I am not going to sail on this boat again". or even worse "Shouting at people is the right way to manage a boat"
  5. And one should never forget the human factors... I'm completely convinced by the case you and your father put for the 49er et al mainsail cuff. It seems to me it just has to be a good thing even if it counts as measured sail area. So when I got a new main for my IC I sized it so there was the area available for a cuff, and I had one made. It lasted about three races. The reason is that I don't use a self tacking jib, and being unable to sight the position of the jib clew and ensure my sheeting was *exactly* right psyched me out completely. I spent the upwind legs worrying about the sheet position instead of watching the wind...
  6. No-one's trousers ever fell down because they were wearing both belt and braces. Absolutely agree that the first priority is to ensure no-one ever gets anywhere near a turning prop. However its inevitable that sooner or later something will go wrong, and if the chances of serious injury can be reduced without causing unintended side effects that would be a good thing. In other words not a jet drive if the implementation is as poor for our requirements as you suggest. But there is not the slightest chance that the optimal design of a prop operating in open water will be the same as that of a prop operating within some sort of enclosure. The whole business of induced drag and tip losses makes the requirement utterly different. It may well be that no-one has competently designed or at least shipped a ducted enclosure that is optimised for the needs of safety boats and the like, rather than for simply going forwards, but it doesn't mean it can't be done.
  7. Russ Bowler - later half of Farr Yacht Design. That boat was so full of new ideas and techniques that later became widespread its hard to pick on the sail...
  8. The bit I don't understand is why prop guards always seem to be bolt-ons to a standard prop. Seems to me that just has to be inefficient. I would anticipate that the right design would be to discard the prop and install a new unit that is designed to work with the prop guard to be a ducted fan.
  9. I could do that 40 odd years ago on a monohull that had a tiny triangular pole kite - that's completely triangular - it was sailed with tension on the luff. However tacking was a bit more of a problem than it is in the video.
  10. sounds as if reefing the main and a smaller jib would be sensible. smaller jib is a better option than trying to use a furler to reduce jib area.
  11. I think you just have to try it and see. Tying the jib sheets together is a very good idea. 20knots might be pushing it. Work up to it.
  12. Well, try it and see. But it will probably handle a lot better with the jib.
  13. But only in very poor implementations using the wrong sorts of section if you give Bethwaite's research any sort of credibility. Nicky Bethwaite won a Cherub worlds with an over-rotating rig, so its not altogether true that only single sail classes have adopted them successfully. Incidentally at the time they were credited with exceptional upwind speed. They weren't really seen in the class after the Bethwaites moved on, but a lot of that was that it is extremely hard to do a decent Bethwaite style mast in aluminium (the Tasar mast is rather compromised). Carbon and other fibres open up all sorts of possibilities that are to my mind yet to be explored. What has happened though, since Bethwaite's research, is that pole masts have developed dynamically way beyond anyone's expectations, and we have learned that the dynamic response of rigs brings enormous benefits in boat speed and handling. Bringing those benefits to a rotating rig that supports a spinnaker seems to be very challenging. We've also leaned that a lot of the old thinking about mast drag and section shapes was hugely overstated, and a simple pole mast isn't nearly as problematic aerodynamically as we always thought. In particular the old thinking about advantages of a smooth leeside flow seems to have been fundamentally flawed. I've never had the slightest concern with kite halyards, and in these days of masthead kites any problem is minimal. Similarly there are all sorts of options with mast bend. But getting it all together is a big challenge, there's no doubt, which is why I haven't tried recently!
  14. I had pretty much the same discussion fifteen years or more ago with Alex Vallings of C-tech, who's one of the people who has tried and abandoned radical rigs on Skiffs. As I recall what he said was something on the lines of - if current solution is at 95% of potential, and new concept is at 70% of potential, which would be pretty good for a first pass, how big an advance does new concept have to be to look fast? I can't speak for AV or the others, haven't talked to anyone about what they abandoned radical rigs, but my thinking has been something like this. I first had a wing mast on a dinghy of mine back in the 70s, and I've played with them intermittently since then: indeed there's been a Bethwaite wing mast in my garage for the last umpteen years. However its one thing to give a concept a good go and see how you get on, and quite another to do a real development process if you are just a self funded amateur - or even owner of a small business where you have to fund it yourself in your own time. My feeling is that if you're developing stuff on your own, whether as amateur or self funded professional, then a serious development process *guaranteed* to deliver whatever the potential is in an idea is going to eat up probably half a dozen masts, twice that number of sails and goodness knows how many recuts. And even more to the point, if the only real comparison you have is class events, its going to eat up three or four sailing seasons in which you are going to be uncompetitive and inconsistent. That's really quite a chunk out of your sailing life and your wallet. And if it turns out the potential was never there... True, a professional sponsored sailing team with two boat tuning, full time sailors and ample budget can compress all that into months or less. And even a handful of committed amateurs, if they are local to each other, can get results quickly and within a reasonable budget - 6 masts and 12 sails between 3 people with two boat tuning exercises or just weekly racing is a lot more practical. But if you haven't got that... I've three times considered radical rig projects on top of new boats, but every time I've reluctantly decided that actually I want to play it a little bit safer and actually go racing, not just be testing within a racing fleet. So to my mind that's the reason why the things get dismissed. Its one thing to build a rig and give it a good go mate, but if your good go comes up disappointing, well its quite another to put in a sustained development process. But going back to the OP, to my mind the 14 is the wrong platform for radical rig development. They have both a lot of restrictive rules (although nothing like as bad as they used to be) and a long history of banning radical developments if they show potential. There are other boats that would be a better choice.
  15. But your OP seems to suggest you don't think its been done right.