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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.  

Daniel Holman

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About Daniel Holman

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  1. Gitana Maxi 17

    It’s not honeycomb it’s pinholed foam - ie foam intended for use under vacuum to prevent voids. The black spots are where the (black poss spa bond or some such) core bond adhesive gets into the pinholes which show that the whole vac bonding is working. The foam is probably the very dense stuff that has similar mech properties to oak. I dare say that structurally this is fine assuming there is a spar and like what somebody said, either damage or cavitation, which will eat bronze propellers. Think 40 plus kts alone won’t cause cavitation, but 40 plus kts plus enough negative pressure to “boil” the water, the subsequent collapse of the bubbles being what erodes the surface of the foil / prop. in propeller world, among other things you might look to reduce that pressure by increasing blade area, diameter, reducing pitch increasing revs or some Combination therof. Did any ac boats get this sort of damage? I suspect that the more offshore scenario of very variable loads with boat motion combined with going in and out of the waves in a transient manner may have precipitated this, and it probably would not be straightforward to just up the area. Making it monolithic would not help if it is cavitation erosion, you are still basically taking an watery angle grinder to the surface. Harder substance ie metal may reduce the rate of erosion but then you are into something heavier and bendier. Dan
  2. Blue Balls

    Quality well done plenty time to get her “bay proof!”
  3. VPP for dinghies and skiffs

    I could see that being the case. Only used that technique once, don't own a GPS, but it was interesting and esp if more than one boat in a race compares tracks it could be pretty interesting.
  4. VPP for dinghies and skiffs

    Its a good piece of work, Sosoomi, although I reckon empirically in 10kts or more SOG at VMG angles would be ~ 4.5kts for RS200 - reckon if you fudge to fit to that the rest of the polar would be very valid. Computed polars are the output of VPPs and are used for 2 things - some yacht handicap rules, and for getting target boatspeeds. On a yacht with (properly calibrated!) instruments with SOG and TWS and TWA then you look at your polar especially upwind and also VMG running (when not in tactical situations where you are not on VMG angle) to work out whether you are sailing too high and slow, or too fast and free, i.e. to make sure that the optimum balance between induced drag (reduces with speed at same RM) and frictional drag (increases with speed) is met. Think many VPPs have optimum heel angles as well - important as with heel comes RM but you lose some efficiency and CLR moves. I'll be honest I don't see the value in the measured stuff. Even if you were clever and only sampled it during "steady state" sailing. You never know the TWS or TWA accurately enough on a dinghy for it to have value, and of course both change pretty dynamically, as do most things on a dinghy. Dan
  5. I14 Capsize Compilation

    Good stuff, bet you slept well. plenty of that in the UK last few weekends.
  6. Small home built beach cat?

    Home build small beach cat? Youll be wanting the woods designs pixie, seen on this YouTube round the corner from where I grew up: plans can Be bought from: http://www.sailingcatamarans.com/index.php/designs-2/46-beach-cats-and-dinghies/5-pixie-14
  7. DC Designs

    Cheers guys how about the stringer frame boats i.e. as distinct from stressed ply - Machete etc
  8. DC Designs

    Hi All, What scantling is used in the ply only IC's to get a boat down to 50kg sailing weight? I.e shell thickness, bulkhead thickness and spacing. Also Stringer scantling. Cheers!
  9. Legal "Wingmast" for I/14

    Yep that is cuckoo #3. I think a number 4 is imminent. My intent was certainly to get a narrow waterline, but it still measures in as per r.o.f by a mm or two so that part of the intent was met. I think Archie in #2 has been having some race wins and great flashes in all conditions mixed with a load of teething issues. My season has been heavily interrupted by arrival of a second child. I only lined up properly last weekend vs other 14s and again had good spells but was rusty as hell, some rigging errors etc, some changes needed on rig. POW is in a few weeks so hopefully we can be all sorted and get a better idea on performance.
  10. Legal "Wingmast" for I/14

    No sweat - always helps with the motivation / progress when trying to execute one's own silly design and build programs in the midst of a young family!
  11. Legal "Wingmast" for I/14

    Think that you get a really big range of conditions in the U.K, plus there has never been that much culture in 14 of developing condition specific kit, possibly as a result of the expense, people choosing more to try and get the best through the range out of their rigs. You can get 4 seasons in one day here as well. some people run 2 jibs as allowed by rules but it only really opens you up to psyche out when you have to chose one. Seems on the whole that the U.K. Teams are superior internationally over the full range of conditions, with some Aus teams being very good in the breeze, some of the other international teams being strong in the light. Whether that is down to weight or condition specific setup or just skill/style it's hard to tell.
  12. Performance gains without two boat testing

    Sog upwind maybe nearly wind speed up to 10kts in flat water up max to 12 kts on a very good day in wind. Bit footy. Less in waves. Bit more than wind speed downwind but topping out at high teens on vmg angles. biggest top speed instantaneous I've ever seen (by someone else) is 25kts. Think a new one sailed well will just have the better of a well sailed 49er in sub 12 kts, above that 49er rm takes over.
  13. Performance gains without two boat testing

    If you are using a 505 to tune up something is very wrong with your 14 sailing. well sailed 14 tacks thru 50 deg ish give or take I don't think that's far off beach cat with dagger territory.
  14. Performance gains without two boat testing

    Yeah time on water in a rigorous fashion focusing on going round corners, going through modes and gears whilst under pressure will make you better at sailing and yield decent results as long as your tactics are sound. I'll be honest for assessing developmental gains, apart from trusting your backside (ie seat of the pants feel) I think that apart from a very serious multi channel acquisition syTem and post processing capability, everything else is pretty dodgy at best. Its very easy to get another half knot letting some vang off, which won't be easy to associate with a couple degrees less height unless you have some very clever measuring stuff. Thinking laterally do you know anyone local with a 49er to line up with? Or a fastsh beach cat? A 14 should do a hobie 16 upwind but an f18 would probs do the 14. Maybe something in between.
  15. Legal "Wingmast" for I/14

    Ben Gs effort is really first class I chanced upon his blog a while ago. Well considered design really nicely done execution - I hope he is getting lots of fun from her. Its bloody interesting this whole subject, and something I have dabbled in a bit with varied results. I think that the 6 masts 6 sails thing is a decent if conservative basis if you are going for an entirely new rig concept. You get to a paretos law situation ie the first 80% of results come from the first 20% of effort, The last 20, or realistically 10% towards perfection, whatever that is is the hard bit. Obv if you are just having a go at a sail only that is a different story. A good product for smod use will require a lot less finessing than getting last 1% performance in a development class. The effort for smod is in designing enough cost out whilst keeping sufficient capability. I think that if the sailor or owner of the process is either a sailmaker or engineer, the process can happen a fair bit quicker. Similarly if the sailor or sailors have a really keen engaged sailmaker/ spar maker on board (often but by no means always a function of potential earnings ) then that can significantly expedite things. if it's just a sailor or sailors pushing shit up hills with an Unengaged sailmaker/ spar maker then it's a bit of a case of how many monkeys with typewriters are needed to write the collected works of Shakespeare. These days some bigger lofts and spar makers have sophisticated software that can do coupled aero and structural calcs that can significantly fast track these sort of wholesale rather than incremental developments. In big boats they make a lot of use of that, but as you get smaller the cost of making prototypes becomes competitive. Of course as with all software, rubbish in rubbish out so somebody has to know what they are doing and what they are aiming for. Absolutely agree that if results on water are your primary concern leave all this shit well alone and cherry pick what someone else has done once it's mature and demonstrably better than what went before.