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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.  

Rob Zabukovec

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About Rob Zabukovec

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    Anarchist

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  • Location
    Tasmania
  • Interests
    Multihulls, especially Proas

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  1. It is fag packet stuff... Basic physics. Just waterline length, displacement and sail area. Not including wing masts. Texel, MOCRA and OMR basically work along similar lines, albeit with their own versions of factors for mast, sail, prop(s) and foil efficiency, plus bias for boats with headroom/accommodation. if you want to work it out for yourself in more detail, do a trial Texel rating. It will give you speeds and sail carrying predictions. Play with your sail areas. You will get different speeds and different stability predictions which you can interpret or adjust using your own experience of the T35.
  2. FWIW, the fag packet flat water speed prediction formula in my data base give you a max upwind speed of around 12.7 knots and around 25.4 knots top speed. So you are sailing your T35 at nearly full potential. The only real improvement to come should be with a big flying Genoa in light up winds and medium reaching winds. With a 40 m2 flying Genoa, if you can carry it in enough wind, could give you around 14 knots and 28 knots respectively. Standard jib only SeaCart 30, you should be about the same or slightly faster. Ditto Dazcats, depending on which one and which rig, but they should be faster upwind in big waves due to greater RM and huge inertia. Both of these boats can carry really big flying genoas/screechers. But as Samin has pointed out, a lot depends on how well a boat is prepared and sailed......
  3. Looking forward to hearing how it goes. For the benefit of my data base, what do you reckon your top speed upwind is/will be, your absolute top speed and how you compare against the SeaCart 30? Thanks in advance.
  4. And get a larger light weather genoa......
  5. I rest my case. Ditto T foils. They are heavier with extra load on the rudder fittings, and in light winds, when not lifting, they are extra drag. Pitch reduction is important, especially on a boat like Groucho's, where the weight of the extra tall mast is 13% of light displacement. On the T35, that would equate to a mast weight of over 200 kilos. I know of a 9.5 metre Proa with a mast weight of only 2%. And if a T foil allows you to drive a boat harder/faster in heavy conditions, that must put extra load on in other places as well. It sounds like the T35 is already on the load limit?
  6. You mean like this????:
  7. Don't worry Gary, I like Sid and the way you have a go at some pretty radical stuff. I have sung your praises on other forums: https://proaforum.com/forum/viewtopic.php?f=5&t=212 The offshore comment was simply to highlight the fact that what works for a 230 kg harbour foiler may not be appropriate for a 1300 kg Tri with at least the potential for offshore work.
  8. Next AC boat? Not to my knowledge. It is 8.5 metres LOA with an 11.5 metre long mast which weighs roughly 30 kilos. And I wouldn't want to go offshore in it.......
  9. Groucho's boat. My mistake, it is 230 kilos, not lbs, so 18% of your weight. And 8.5 m LOA.
  10. it all just needs to be thought through for each specific case..... but the chances are that there will be some extra weight and load, in places that may not have been originally designed for it. Unless the adjusting control system is entirely mounted on the shroud, including locking off, there is a turning block somewhere which increases attachment load significantly and depending on where the block is located, puts either the crossbeams or the mast under increased compression and in any case the mast step under increased shear. And what you can do on a boat which is less than 10% of the weight of the boat which we are talking about is entirely another matter. And is your boat ever likely to go offshore for extended periods?
  11. Additional rigging, pulleys and control systems equals more weight and load. More vertical pull on the weather chainplates, and extra load around control systems, mast pivot etc possibly means more reinforcing which is extra weight and load, especially as you can carry more sail at higher wind strengths.
  12. Increased performance, however you try to achieve it will increase loads. Even a canting rig. Increased loads means reinforcing areas of the boat, adding weight, which in itself adds loads. All of the above comes at a cost rate way in excess to the increased performance gained so maybe you have hit the wall? Get a bigger light weather genoa, loading up the boat to its max earlier and then just keep reducing sail area to keep the loads at the max acceptable to you. You need a good multihull designer, preferably the original designer to tell you how much more load you can take and where. Or how much reinforcing will be needed and where. There are no easy (load) free solutions. Good Luck........
  13. So now that we know more about your Tri, it looks like: 1) Maxing out your fore triangle for light weather (see below) 2) Canting rig 3) Float rudders and no main rudder would be good, less drag, but not possible with existing floats..
  14. Wouldn't disagree with any of your comments..... I was thinking of maybe some more basic things. No obvious prod or bowsprit and presumably no flying lightweather headsail/screecher. Practical but not fast recess in the side of the main hull for the outboard. Old style ama shape. Or if you are not flying 2 hulls, just sail the boat harder.