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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.  


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About MultiThom

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  • Birthday 07/10/1950

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  • Location
    Benicia, CA
  • Interests
    Trimaran sailing; sailmaking; boat rigging; SeaRail 19 Trimaran Google Group
  1. SeaRail 19 Folds

    Not specifically on-topic, but an earlier (2014) SeaRail 19 appears to have hit the used market. It is in Wisconsin and in the photos it appears to be in good shape. Good deal, too (only 19K $US). This is an "insert tube in socket" and not the folding boat. Truthfully, there are a lot of nice things to say about the original design....shorter bowsprit so it doesn't need a bobstay. It is lighter by a hundred pounds or so which will translate to a little better performance. Since there are only 15 or so SeaRail 19s in existence, I thought I'd pass along the info. I don't expect it to stay on the market very long given how the season is starting up again. http://www.boats.com/sailing-boats/2014-searail-19-6348151/#.WosMrjdG36Y
  2. Wing Sail Design

    Thanks again. Interesting read and makes me wonder why BMW-Oracle chose to change from soft sails to wingsail in the AC match with Alinghi way back when since the races were required to be done in light breeze...they had to have read this analysis and it says that the soft sails had an advantage in lighter breeze. I also found it interesting that both Aquarius and Nylex couldn't use all the rig power in anything above 10 kts breeze (something that seems to be a common thread in my more recent boats). My first boat I was in "seeking power" mode all the way to 25 kts breeze or so (F242); this SeaRail I have now I start dropping traveler (shedding power) when I see whitecaps (12 kts).
  3. Wing Sail Design

    Thanks, Doug. Liebecks High Lift single element explains soft sails design. Max lift seems to be the desired outcome...but since we don't have motors, I guess I'm confused that the max lift isn't angled to provide max thrust in the direction of travel...or maybe that is done by angling the boat and the whole wing. Not having ever sailed on a boat with a wing sail I haven't seen how it's done. Thanks again, curiosity is assuaged.
  4. Wing Sail Design

    I'm an amateur sailmaker/designer. Never want to do a wing sail; but I am curious as to the placement of the pivot that produces the camber in a wing sail. When I design a soft sail, I typically place the max camber between 35% forward (jib) to 45% forward (mainsail). When I see photos of the wing sails in use, I see the pivot typically further aft of midpoint. Granted, the wing mast does move the actual COE forward some...but in most cases it looks (visually) to be aft of mid sail. Friend posted (Facebook) a photo of a catamaran with a wing sail going up the Napa river today...nice boat moving right along, but had the pivot even further aft than AC boats. Anyone have a reference that could explain the aerodynamics? Probably Oracle owns everything, but...
  5. Affordable racing tris vs. cats (<35ft)

    Well, not much help, though, for the OP. He sails in San Francisco Bay that has "big wind and moderate chop" and also isn't interested in looking offshore for a boat. I know that thread drift is common on anarchy sites...
  6. Astus Upwind

    I've discussed this with Phil related to the SeaRail design and it is similar (I'd buried my lee ama in only 13 kts breeze)...floats are meant to submerge until the front aka hits. Sounds fun but will take getting used to. I guess it makes sense, sorta. My submarine (Albacore hull shape) went faster submerged than surfaced. Getting tired of winter...
  7. Astus 20.5 new VPLP trimaran

    I used a VPP on the published numbers and figured that their weight estimate was off by 10% light (which is probably about average)...I get the sport configured boat being faster than a Pulse by a little-about the same speed of my SeaRail (with an actual weight for the SeaRail). Here's my guesses...600 kgs with 2 crew; 51 sq meters of all sails; 5.95 meters length. Faster than the 16.5 Astus by a little (again, on paper...can't tell how it will point or handle chop or ...).
  8. Astus 20.5 new VPLP trimaran

    It sure does look like a nice pocket cruiser. Ought to be good competition for the Farrier and Corsair boats even though those are larger. Doesn't have many negatives and has some nice features (like halyards internal to the mast and an actual locker for anchor and fenders). Well thought out space usage. Selden hardware...reminds me a lot of my old F24 but I expect this boat to be a little bit quicker.
  9. Affordable racing tris vs. cats (<35ft)

    I did look at Bspd but didn't care for the online UI. Prefer to plug and chug something if all I'm doing is comparing two boats to guess which might be a little quicker. None of the formulaes will tell which boat can point best nor which will handle chop of various different sizes/frequency....related to internet info...yah, the folks are usually "optimistic" particularly with weight but usually within 20%. Sail Area is usually pretty close as is the length. Basically ratings are worthless exercises (IMLO) since no two boats will sail consistently on all points of sail--look at any two polar diagrams and you will see what I mean. That's why I prefer a rating system that takes skill, luck into account so that the amateurs always have a chance...
  10. Affordable racing tris vs. cats (<35ft)

    Tell me you aren't putting sweeps on the bow.
  11. Affordable racing tris vs. cats (<35ft)

    Concur that ORCA has a decent rating system that is designed to get people out racing. In an amateur sport, folks deserve a chance to get better and still look forward to playing. Personally, I use the basic AU formula (omitting all the tweaks that make it hard) to determine a GOOD GUESS which boat could be faster. It is a variation on SA/D and I use internet published numbers so no weighing or other excrement. All measurements in meters/kgs (Take Length to the 0.3 power multiplied by the total sail area (including downwind sail) to the 0.4 power) Divided by (weight in kg plus weight of crew) to the 0.325 power. Faster boat will be the one with the largest number. All the tweaks that Texel and AU use are to adjust for different wing sails/high aspect ratio sails...yadda yadda. Not worth my time/effort since (as ORCA knows) skippers do make a difference.
  12. Affordable racing tris vs. cats (<35ft)

    It's probably the vaka that works like the governor...that's the hull that is always dragging (at least until you get into the 65 foot range with big foils). Yes, a quibble; sorry. I admit to preferring tris; but I sail for fun and the occasional thrill. I tried a cat (a slow one) but never could relax when sailing solo; hence I bought another tri. The wind is typically gusty and shifty and in the 20s in the Carquinez...great fun on a tri, scary on a cat.
  13. Affordable racing tris vs. cats (<35ft)

    There are some older F31s in your price range. Most out of the bay area tho. Nice thing about trailerable boats is they can be fetched easily. I will say that racing multis in the bay is fun. Unless you are in a Weta, no one designs so it is best to get a design that the rating committee has some experience with, though. That way you can be somewhat assured that your rating will be fair. F31 is a good choice.
  14. Affordable racing tris vs. cats (<35ft)

    What you really want is Shadow (1987 formula 40) which is for sale in SF. But it is both longer and more expensive than you want to pay. Given your experience, I'd stay away from the F24s, 750s, Dash; I raced an F24 and it is a dog in breeze less than 10 kts. (lots of bay races have dead or near dead air). You didn't mention the Multi23s brother, the Diam24. You will spend a lot of time mounting and demounting either of them, though. You ought to take a walk in Richmond marina...lots of fast boats just sitting there; maybe find one that fits. I also think Antrim's Erin (30 foot tri) might be for sale.
  15. I live and sail in Benicia CA on the Carquinez Straits which is near San Francisco Bay and half way to the delta. My normal crew from racing years past have all moved or gotten out of sailing so I'm looking for someone-preferably close-to help me. I've sailed trimarans now for 20+ years, so I am experienced, but it never hurts to have someone to help when things go awry. I probably won't race much (been there, done that, got the tshirt) but might do one or two events. Boat is a small tri (SeaRail 19) so one crew is all that's needed. Carquinez has lots of current and lots of wind most of the time. I expect to see 20 kt boatspeed so should be exciting. Contact me by email tpdavis@yahoo.com if you want to check that "multihull experience" box.