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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.  

JulianB

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About JulianB

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    Sydney mostly

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  1. VPP for dinghies and skiffs

    The ultimate VPP is an empirical based polar. Because the theory that creates the VPP better match the empirical data or it's not worth a crumpet (by definition). (Way too many people try to get the data to match the theory and aint that an error! ) It quite easy to generate the ultimate VPP graph (because it's empirically based) from a polar, just takes some time. Watch this space. Jb
  2. VPP for dinghies and skiffs

    As I said, lots, 29er in Austria. Max speed was 14.8knts, mountain lake "Attersee".
  3. VPP for dinghies and skiffs

    How many do you want, this is a 49er in Syd Harbour. 19th Oct BOM, gives the wind at 10-12knts SW, but the wind beacon close to the sailing venue had it at 12-16knts, avg 14.5knts at 6m height. Max boat speed was 20.6knts, long std gybe, lots of upwind, plenty of tacks, about 7nm sailed in little over a hour. For those that know Syd harbour, most of the sailing happened around the Pigs.
  4. Swollen 29er foils

    You are allowed to repair, provided you don't try to gain an advantage. It has to pass the "pub test". But otherwise, it would be OK. Need to stress, it's not my call, it's Barry's in Perth (AUS). jB
  5. Tasar Single handed

    25% increase in efficiency on a reach when you're trying to pull hi pressure differentials. Only 5-10% reduction in drag closehauled, because of #1 much smaller LE radius and #2, masthead/tip hooking to windward. But yes, you feel it, no question. Jb
  6. All up weight of a Laser?

    Huge difference between hull weight and all up weight. A Aero maybe 45kgs Hull weight, but near impossible to be 45kgs all up weight. 45kgs is also the hull weight of a Byte. I believe the Hull Weight of a Laser is 64kgs, The 2 alloy mast sections of a Laser are 10.4kgs. Boom-mainsheet-vang would be tad over 3kgs, Mainsail tad under 3kgs, centerboard would be also tad over 3, and the rudder-stock-tiller, tad under 3kgs. So 64 + 10.4 +12 = 86.4kgs = 190lbs.
  7. 49er Updates

    There was an interesting piece coming out of Kiel Week on the YouTube footage, from Marcus Baur, a week ago (with Clean as guest commentator) saying basically in the early days the boats were perceived as un-sailable by anyone but Australia's (and Kiwi's) and he, as a German, had a very hard time. Now they are being pushed very hard by just about every country, and the girls are pushing them even harder. What was considered a great boat in 2002 - 2010, would be considered a bit of rubbish now, and it's the same for every class, even the Laser and the Opie have had to refine their building process. I know the 470 has, the Finn and then we can start talking about the Nacra if you wish. Biggest changes where the new moulds, we reverse-engineered the hull and CNC cuts new plugs, and then made every new mould off the same set of plugs (which are in NZ). That lead to far more accurate framing, and that has lead to longevity! And the rig, initially the rigs were fine, but then as people became confident they basically drove them so hard they destroyed them. Again you're seeing the same thing with Laser top-sections now. It's inevitable. The Carbon rig has dropped the running cost of a 49er dramatically. Once that happen, & the FX girls needed 6:1 on the downhaul, boys said "me too" but the boys are stronger, so they started tearing the lower seams in the mainsail apart. At the same time, boats upped about 2 knts downwind, so we over ran the spinnaker, yada, yada, yada. VW/Audi changed the spec on their air-bags, and another German medical company agreed with VW, happens to be the same material we make spinnakers from, but they use 50 x as much, so new material, time for a new design, a new flatter spinnaker. Happens to be about 1m² smaller. If you're a Weekend Warrior then does not matter if it has sliding wings or pinned wings, you won't ever reach the full potential of the boat until you have sailed it into the ground! A carbon mast, just for "bang for buck" ratio is a must! Old foils, will probably suit you better, bit more forgiving. Jibs have not changed for a while, Mainsail has a gusset in the front to stop over enthusiastic boys destroying the sail in one outing, but provided you go easy on the downhaul, again you won't ever reach its full potential. Same with the spinnaker, you need to be doing 22-23knts in 16-18knts of wind to really enjoy the fruits of the new kite. It's smaller, fair bit more twitchy, but it will take you up into the 24-26knts range and the acceleration is spectacular, and it now appears faster in anything over 6knts (TWS) but until you're at that level, the old kite will give you bags of fun. Just go have fun and enjoy the learning curve! Jb
  8. Legal "Wingmast" for I/14

    Hi, in deference to Dad, the major reason why wing mast are not "cost effective" and by cost here I mean performance, is that the skiff carries a quite low lbs/ft² or kgs/m² compare to say an NS14 or a Tasar or most multihulls, so the advantage gained by increasing the pressure differential, by using a rotating mast or a cuff luff is grossly outweighed by the complexity. I assure you we tried it, particularly the cuff-luff with the LE fairing, we hot wired EPS foam. Bora did it not so long ago on his Moth, we did it 20+ years ago. But complexity outweighed benefit and it was discarded, pretty quickly. DW as soon as you pop a spinnaker, then any argument to increase CoL goes out the window! Not saying it won't work, but more so because of the drag reduction coming from the smaller LE radius. Total drag from a mainsail set behind a round mast, like a 49er is only 15.4%, and the jib alone is 12.3% (of the total drag pool) so the drag of the mast itself, is going to be 2-4%. To put that in perspective, if the 2 crew trapeze at different heights, you will generate more drag than the entire mast. There are better, more efficient places to reduce drag. With the advent of foiling and the dramatic reduction in Hull (hydro) drag, then the whole game changes. mostly the significant "over canvassing" that has been a part of skiffs for literally hundreds of years, will become more modest, and we will see another Russel Bowles, or a Terry McDell or dare I say Bethwaite minimalisation drive and the sail area will become less and then you will see increase in things like cuff luffs with LE fairings. But with 230+ ft² of UW area on a I14 (or similar on the 49er) the gains are just not there. Think about the clothes you wear and lock in, trapezing UW, and the gains will be greater. Things like rope trap wires are very light, but they are also very draggy, much more draggy than similar strength 1:7 wire. For the extra 50gms in weight, the wire ain't all that bad.\ Jb
  9. Swollen 29er foils

    My pleasure. I possibly get more of a kick out of "more mature" sailors giving it a go (mostly in 29ers) and having fun than the rock stars in the 49er or the aggro parents in the 29er. I was once taken to one side and told to stay away from Parra sailors and youth. The sailors, particularly the Parra sailors are amazing and beyond grateful and getting random hugs for 14-year-old girls (both able-bodied and special people) is a tad "awkward", but shit happens! The coaches and the parents occasionally need to take a reality check! But it looks like we will have the biggest year ever in the 29ers this year, Ovington is yet to come off double shifts and I can't get enough boats for HK worlds. Nice problem to have. Alloy foils were great, pity about the EU, but from adversity comes opportunity and the FRP foils are possibly better. Not 100% sure why yet, took 2 years for a professor from MIT to tell us why the cuff worked on a 49er (and 29er) back in 1998. Then took dad another 2-3 years to verify it. Don't have dad anymore, so it will take me longer! And we have learnt whole bunch more indirectly in the last 6-8 weeks about the cuff and the foot of a main, having lots of fun. and lots of stuff coming "down the pike". TTFN, Jb
  10. Singlehand 49'er?

    Re re-righting, I can do it in under 10 knts. Warwick could do it in under 8knts. he's my age, 65-70kgs, Im guessing I have attached a photo of Harry doing the "regal thing" in Shanghai last year. He is about 72kgs and can get it up in 10ish knts. He's 27, I'm just about to click over 60. 57 babies, love em! yep, age makes a difference so don't wait too long! JB
  11. Swollen 29er foils

    Im back home if you need any more help!
  12. Singlehand 49'er?

    It all depends on how big you are. I'm 95kgs (210lbs) and 1840mm, (bit over 6ft). Taking a 49er upwind in 6-8 knts of wind single handed is something that few will experience but it regal! The old FD was a regal boat, especially the timber ones, just a joy to behold. Lightweight Sharpie was a dirty regal! The old timber 18teens, when they were 8ft wide, where regal. It a feeling that is hard to compare, it's beyond special, it's cerebral. And until you have mastered it, you just don't understand. 29er one up is 1/2 way there, has to do with efficiency and power to weight ratio Your point the eye out of the needle, probably upwards of 25° true, down in the sub 15°s AWA, and you're doing 1.3-1.5 time wind speed. It's just eye-popping and it never fades. Could go upwind for hours doing that, the only bitch is you have to come downwind, that's fun but a very different fun, maybe with the new flatter kite it could be great but one up, you had to slow the boat down, otherwise, you overran the chute! (AWA was simply too high to get it to set) Sure, I'm biased, but Warwick Rooklyn and I used to take 2 x 49ers out mid-week one up, and he is damn sight lighter than me and not nearly as tall and we just had a ball. Yeh sure, if he'd capsize, I had to also, swim across and get him going again, then get back up myself, but as long as it stays under say 8-10 knts, you will never regret it. 12-15, its interesting, and 15+ then you need to be f--king lucky (go read about Garda when we got the boats up for the Olympics) and really that was not regal, it was scary. All's well that ends well, as they say, but that could have been a disaster If you got the ticker (can't say balls anymore) and willing to have some swim, before you get it right, its an experience beyond any other you will ever experience. You know, we sailed 18teens yearly in Lake Geneva for about 3 years, sure it was impressive but it was not regal! 49er is doable in 6-8 knt one up, and if you ever get the chance, do it!!!!!!! Jb
  13. Swollen 29er foils

    You have probably by now solved your problem, the fact that its now summer for you suggest your not antipodean. Pu is very interesting stuff, lots and lots of people tell you lots and lots of different stuff. But, what seems clear is the really light Pu foams, so the H20 and H25 (so that's 25kgs/cb-m) have cell stability issues, either they collapse or they don't cross link. Either way they soak water. If you have a old board that has soak water for a very long time then its very possible it gone the full length. If you really want to fix it (I would go buy some FRP ones) then get a lot of the foam out. (Once ts cured then acetone wont do it, its stable, so you have to get most of it out.) Would not suggest rolling your mothers car over it, but bits of timber with clamps dose work, and once it back into shape, then back the clamps off but don't take them away. Get yourself some H32 or H35 foam, make sure it 20 -24cc and re blow them. Make sure an end is open so it can vent! The stuff sticks to just about anything, it all happens in about 4 mins, but leave the clamps on for 1-2 hrs. If you can heat it to 40-50c, then that will accelerate the foaming process and "kill it", (the term in the industry), you complete the reaction. Normally Pu is used blocks or big metal presses. Your matteres, most of your car, chairs, even lots of mobile phones are all made from Pu, its a truly amazing material and it relies on exothermic reaction to fully cure. Can get to 150c inside a 500mm x 500mm block. Anyway, once ts "killed" it wont expand any more, it could even shrink, but not much in the thickness of a 29er foil. The Epoxy foam, lightest you can get it to is about H170, you can lighten it up with EPS [Expanded PolyStyrene], bean bag balls] and when encased in epoxy its pretty impervious to water. The lightest you will get it to is H80, maybe. Even at H80, it makes your centreboard pretty heavy. Sorry I did not come back earlier, in Italy, got a bit on right now, home in 12-13 days, be more regular then. Jb
  14. Swollen 29er foils

    The problem is that the EU change the regulation on the Pu (Polyurethane) foams that we were allowed to use and the new-er foams, which used less "exotic" chemicals, did not fully cross-link, so they, as you right put it, swelled. The answer is to remove the end cap, and remove the last 25-50mm of foam, then with a rubber mallet, you can panel beat the alloy back down to where it used to be, and if your really smart, you make it even a bit smaller again, that way it becomes very easy to get them into the case or rudder stock. There are some great expanding epoxy foams on the market, one we use a lot is Sicomon, a name like that, it's French, works pretty well and you just mix up a brew and re-blow it. You can then just finish it off with epoxy resin, and your good to go! Jb
  15. Traveler Designs

    I am no multi hull expert (even though I sail on a tri that has won 9 out of 12 OMR national championships) and its a sloop rig. But WRT a cat, particularly a A Class that is very refined in terms of hull shape, and by that I mean there is very little reserve, it close to the end of that thin wedge of design and its not even similar to a Moth on foils. Cat's and particularly the hulls you have on your A Class are in that weird area, used to be referred to as a 10:1 rule, where if a boat's WL width was less than 1/10 of it over all length then it "cheated" the HS [Hull Speed] law and had minimal drag way beyond HS, but still hit the same brick wall latter down the track, because it can never plane. So what I am saying is that because a A Class has such low drag, at low speed, it needs very little AoA to generate optimum lift ratio's, even more so than a moth on foils. At higher wind speeds you have twist, generating the AoA, and I do remember Fred Eaton's C Class where they tapered the foot of the mainsail, because its just there as a end plate anyway, the great bulk of the lift is coming 2m above WL due to wind sheer, etc. I hope someone else comes and explains it better, but it makes perfect sense to me. Had not extended my thought to Cat's or Tri's or Proa's. The topic was Lasers and Aero, but your's is a very valid extension! Jb