svendson

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About svendson

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  1. svendson

    Spindrift 2 Jules Verne 2017

    Thanks for that link to Fralo's site stief, good stuff. That FOCUS magazine you linked also has some nice info and insight into the organisation and logistics behind such a sporting endeavour. Super happy to see some first hand English content for one of these attempts, hope other teams follow suit and add some English subtitles, seems like such a low cost way to get much wider exposure. As far as I can tell, changes for this attempt from the last one are: new main foil tips, look very much like the boards on Sodebo now T-foil on rudders Reduced weight due to: 12 crew instead of 14 new, lighter sails "other" weight reductions are mentioned but found no specific details. Anyone know what those kinds of weight saving efforts look like on a boat that was launched as a cost-no-object marvel of modern rope work? The usual replace ss fitting with soft attachment probably doesn't apply here... Still running the shorter mast (by 3m) compared to Loick's go round as BPV. Yann reckons they can't shorten it any further due to the platform weight, they'll end up too slow under 18 knots TWS. Hope they get a weather window soon!
  2. svendson

    Spindrift 2 Jules Verne 2017

    Any info on changes to the boat since the last attempt? I thought she was given more than just a refit but can't find anything from the team or media outlets.
  3. svendson

    Is this the Figaro III?

    Very cool looking boat. I just can't help thinking it would have been a lot more appealing for anyone without a big bucks sponsorship if they had just kept the water ballast instead of the foils... or gone with a fully retracting DSS type foil assist...
  4. svendson

    Best Sailing Knife

    For safey, we have Gerber River Shorty's on our PFDs and in the cockpit. Don't find folders to be adequate for emergency situations. Also like that the sheath has no moving parts or springs to rust. Thus far have had zero issues with knife retention in the sheath, despite having it mounted handle down on my left side for easy right handed access. Price is quite reasonable at about 40 bucks. One of 4 knives has a couple small rust spots after 4 years of use, otherwise all good. For rope work I use craft knives or ceramics and just chuck when dull. Would love to get a Boye, just haven't managed to get past the eye watering price.
  5. svendson

    F-22 Update

    Depends. If the mainsail takes the correct shape, the distribution of stress within the sail is correct and whether this is achieved by a more or less vertically oriented mainsheet plus boom, or angled mainsheet alone is irrelevant. However, if you tend to extreme oversheeting of the main in the interest of forestay tension, you will pay a higher price with the boomless setup due to a main that is flatter as well as closed in the leech.
  6. svendson

    Farrier F-85SR

    How does a trimaran resist capsize from the pressure in the sails? By pushing the leeward ama down into the water. The amas have a much lower heave response amplitude than the main hull, so any action from beam seas is going to tend to throw the boat onto the leeward ama. So yes, the float rudders probably come out of the waves sometimes. But with far less regularity and far less severity than the main hull.
  7. svendson

    Farrier F-85SR

    I have the F-22 rudder. Makes no discernable difference to the situation I outlined.
  8. svendson

    Farrier F-85SR

    I only have a little F-24 and I sometimes encounter a swell wavelength and size that leaves me with very little mainhull/rudder in the water, even when reefed fairly conservatively. This usually starts to occur when the sea state is getting to the point where I am steering quite aggressively around the worst waves. If I get a set of these inconvenient waves, the 6-8 inches of rudder left in the water after the first one is inadequate to turn the boat in time for the next wave and the boat ends up getting a pretty hard smack. It can handle it, but I wish I had the control to avoid more of those hits. Wouldn't consider it as a refit, but on a new boat, especially one with substantially higher volume floats than my F-24, I would definitely be pretty interested in figuring out a good system for float rudders.
  9. svendson

    Farrier F-85SR

    Umm, Sodebo cut both floats off and moved them 80cm forward.
  10. svendson

    Farrier F-85SR

    There are some properties of high prismatic hulls, regardless of application, that are fairly well known and accepted. They include: -Lower Cr (wave making drag) at high Froude numbers (high speeds). -Increased longitudinal metacentric height. This mean better longitudinal stability at small pitch angles. As long as the prismatic stays reasonably high (ie one end or the other doesn't get submerged or lifted right out), this is true for larger pitch angles as well. Importantly, the area under the longitudinal stability curve goes up, meaning more energy is required to pitchpole. -Increased pitch and heave damping -Increased heave and pitch accelerations -Increased wetted surface area for a given displacement. The last two points are pretty clearly disadavantages for most kinds of boat. The rest strike me as pretty clear advantages for sailboats, especially for ones of the Super Race variety. And probably most serious racers can and do choose to live with the short, jerky motion of the boat as a tradeoff for the increased performance. Many multihull designers around the world seem to have arrived at the conclusion that a high prismatic ama is worth the trade-offs for a racing boat. More recently, with the French in particular, ama design seem to be working on combining a slight bit of rocker for low wetted surface area at low ama immersion (and thus low heeling moment and low speed) with a high prismatic shape at high immersion for high speed performance. The MOD70 and the Multi50 Fenetrea Cardinal (ex Crepes Wahou 3) are pretty good examples of this latest trend. John Shuttleworth observed from tank testing in a paper from the 80s (available on his website) that the transom stern designs of the French boats carried a drag penalty at all speeds and decided to go with a pintail shape for the Ostar boat he was designing at the time. It has been shown time and again that looking at any one variable that contributes to sailboat performance without considering it as part of the system as a whole can lead to suboptimal design (as Ian himself has highlighted). The pin top elliptic roach mainsails of the late 80s and early 90s are a good example of this. Yes, the elliptic profile has the least induced drag. But, it also has the largest root bending moment for a given lift. And so, on a moment constrained system like a sailboat, it is in fact a shape with more induced drag which is best. Maybe this is what has happened with the pin tail ama, or maybe the majority of the industry has bought the hype of the F40 and Orma 60 eras and worked it's way into a suboptimal corner of the design space. Either way, given the dominant trends that can be observed across the field, I believe it is perfectly reasonably to question of one of the few designers who is bucking the trend on a Super Race boat. The weight of the majority doesn't mean the odd guy out is inherently wrong, but it is natural to wonder why he or she has made the choices she has. To give an ad absurdum type example, if a team showed up to F1, Nascar, or any touring car championship with a 3 wheeler, you would very likely be quite interested in hearing why. As can easily be seen on many of the photos floating around the internet, the F-85SR ama is not a high prismatic shape - although it may well be the highest of any F-boat to date. In particular, it is the rocker and v-section shape in the aft part of the hull that gives the biggest reduction in prismatic coefficient. So, it is also quite reasonable to focus on that bit of the hull which is most obviously bucking the prevailing trends. Of course, adding volume in just the stern would affect the longitudinal balance of the boat and as the F-boats are generally pretty good, this is not terribly desireable. And so we get the explanation from Ian that helps it all make sense - in his opinion there is no acceptable way of putting more volume in the bows. And thus more volume in the stern cannot be offset and the running trim of the boat would be compromised. Ian, I sincerely wish your last post had been your only one on this particular subtopic. It was educational, informative, and addressed the subtopic in a positive and professional manner. As far as not being able to get more volume up forward goes, I hold your opinion in high esteem so I am willing to accept that at face value. A folding, road legal trimaran is sitting in a very highly constrained corner of the design space so I imagine fairly small changes in the SORs would have a large influence on what can be achieved in the final design - sacrificing some interior space for higher prismatic amas for example. I think some of the noise being heard around here could and probably should be interpreted as a very small market demand for quickly folding, single purpose racer done to the well known and respected Farrier quality standards, rather than a criticism of the existing design for which the dual purpose SORs have been made very clear. Given your long standing and well advertised disinterest in single purpose raceboats, it is probably a slightly useless piece of market feedback. But then again, depending one's particular outlook and motivations for sailing, it could be argued that labelling a dual purpose design as a Super Racer is a bit of a misnomer as well.
  11. svendson

    Farrier F-85SR

    I got in touch with the Multihulls direct guys about the Farrier options they have - extremely fast, clear, and frank replies every time. Pricing came out pretty much in line with what I estimated self building to cost. I figure that makes sense. They are in a very low cost country, buying in bulk, and I am in a very high cost one, buying at retail. Everything I have learned from previous builders also indicates the you very rarely save much money in the end, you just spread the payment period out over more time. Personally, I suffer from an odd dementia where I would like to build a boat just for the sake of doing it. But, if life keeps getting in the way like it has been the past few years, then I will very likely end up buying from the Multihullsdirect guys when I've saved up enough pennies and get my building fix from something smaller like an F-16 or an A-cat.
  12. dingleberries

  13. svendson

    F-22 Update

    Hole. E. Sheeit! Pure boat porn, that is what I am talking about!
  14. svendson

    F-22 Update

    +1 More eye candy and hot news on the 22, 85, and 32SR please!