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    • UnderDawg

      A Few Simple Rules   05/22/2017

      Sailing Anarchy is a very lightly moderated site. This is by design, to afford a more free atmosphere for discussion. There are plenty of sailing forums you can go to where swearing isn't allowed, confrontation is squelched and, and you can have a moderator finger-wag at you for your attitude. SA tries to avoid that and allow for more adult behavior without moderators editing your posts and whacking knuckles with rulers. We don't have a long list of published "thou shalt nots" either, and this is by design. Too many absolute rules paints us into too many corners. So check the Terms of Service - there IS language there about certain types of behavior that is not permitted. We interpret that lightly and permit a lot of latitude, but we DO reserve the right to take action when something is too extreme to tolerate (too racist, graphic, violent, misogynistic, etc.). Yes, that is subjective, but it allows us discretion. Avoiding a laundry list of rules allows for freedom; don't abuse it. However there ARE a few basic rules that will earn you a suspension, and apparently a brief refresher is in order. 1) Allegations of pedophilia - there is no tolerance for this. So if you make allegations, jokes, innuendo or suggestions about child molestation, child pornography, abuse or inappropriate behavior with minors etc. about someone on this board you will get a time out. This is pretty much automatic; this behavior can have real world effect and is not acceptable. Obviously the subject is not banned when discussion of it is apropos, e.g. talking about an item in the news for instance. But allegations or references directed at or about another poster is verboten. 2) Outing people - providing real world identifiable information about users on the forums who prefer to remain anonymous. Yes, some of us post with our real names - not a problem to use them. However many do NOT, and if you find out someone's name keep it to yourself, first or last. This also goes for other identifying information too - employer information etc. You don't need too many pieces of data to figure out who someone really is these days. Depending on severity you might get anything from a scolding to a suspension - so don't do it. I know it can be confusing sometimes for newcomers, as SA has been around almost twenty years and there are some people that throw their real names around and their current Display Name may not match the name they have out in the public. But if in doubt, you don't want to accidentally out some one so use caution, even if it's a personal friend of yours in real life. 3) Posting While Suspended - If you've earned a timeout (these are fairly rare and hard to get), please observe the suspension. If you create a new account (a "Sock Puppet") and return to the forums to post with it before your suspension is up you WILL get more time added to your original suspension and lose your Socks. This behavior may result a permanent ban, since it shows you have zero respect for the few rules we have and the moderating team that is tasked with supporting them. Check the Terms of Service you agreed to; they apply to the individual agreeing, not the account you created, so don't try to Sea Lawyer us if you get caught. Just don't do it. Those are the three that will almost certainly get you into some trouble. IF YOU SEE SOMEONE DO ONE OF THESE THINGS, please do the following: Refrain from quoting the offending text, it makes the thread cleanup a pain in the rear Press the Report button; it is by far the best way to notify Admins as we will get e-mails. Calling out for Admins in the middle of threads, sending us PM's, etc. - there is no guarantee we will get those in a timely fashion. There are multiple Moderators in multiple time zones around the world, and anyone one of us can handle the Report and all of us will be notified about it. But if you PM one Mod directly and he's off line, the problem will get dealt with much more slowly. Other behaviors that you might want to think twice before doing include: Intentionally disrupting threads and discussions repeatedly. Off topic/content free trolling in threads to disrupt dialog Stalking users around the forums with the intent to disrupt content and discussion Repeated posting of overly graphic or scatological porn content. There are plenty web sites for you to get your freak on, don't do it here. And a brief note to Newbies... No, we will not ban people or censor them for dropping F-bombs on you, using foul language, etc. so please don't report it when one of our members gives you a greeting you may find shocking. We do our best not to censor content here and playing swearword police is not in our job descriptions. Sailing Anarchy is more like a bar than a classroom, so handle it like you would meeting someone a little coarse - don't look for the teacher. Thanks.

SemiSalt

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  1. TAD posted a picture of a metal boat on FB:
  2. This paper from the friendly folks at S&S (Todter, Pedrick, Calderon, Nelson, Debord, Dillon) describes their efforts on behalf on Team Dennis Connor for the 1992 America's Cup. They put a lot of effort into tandem keels mostly because of the success of the Mull-designed USA. It didn't work out very well. It's pretty clear that TDC was underfunded.
  3. Does anyone know of a good diagram of the flow around a Warrick Collins-style tandem keel? I've seen a sketch, which I can't find now, but I've never seen a really convincing illustration of the streamlines. Collins' patent here. I'n not at all sure that Collins would have approved of putting the saildrive in the gap between the foils (Defline 43).
  4. In the discussion of the winged delta bulb, Howlett writes "the wings [are] raised above the maximum draft position to make these less vulnerable to grounding damage."
  5. For completeness as much as anything, I thought I'd post something about Ian Howlett. He seems to be a total guru on keels for meter boats. I found something that he wrote on the internet. It's a chapter from Sailing Yacht Design: Practice edited by Claughton, Wellicome, and Shenoi. The book seems to be out of print, and used copies are quite expensive. Link to the chapter here. The line drawing is a Howlett-designed wing keel for a cruising boat. I assume that when he included it in the book, it was his latest and greatest. The striking thing about it to me is the complexity and subtlety in the shaping. It must be a lot more expensive to manufacture than the usual Catalina/Hunter wing keel. It's probably more efficient, too. The photo is a picture of two meter boat keels (6 Meter, I think) both by Howlett. One with a wing, one without. Not how the wing hangs below the bulb. Not the thing for a cruising boat keel.
  6. It's due to the way the vertical part of the fin disturbs the flow.
  7. Overall dimensions are 15.75m x 3.6 m. Displacement marked on the lines is not quite legible on the scan is 8.32 m^3 or about 20,000 lbs. (That's on the plan;not my calculation. ) Top speed is 21 knots. Power is 636 cu in GMC V-8. Woodward asked Bolger to work out a "more natural-looking" superstructure, so you aren't the only not totally sold on the look. The drawing board name is Ultralight Cruiser.
  8. I was looking through my Bolger books for something I didn't find, but I was reminded of this. Bolger did this design for Stanley Woodward. It was never built. The idea was a simple, very light boat for the Med. More of a picnic boat than a cruiser. It's 15.75 meters (51' 8"). Intended cruising speed 21 kts. It's interesting how different the layout is from Kim's boat with the bridge at the bow. The intended use is not so different, but this boat is more ambitious in some ways, e.g. carrying 3 sailing dinghies.
  9. They suggested that a neutral, no-lift attitude when the boat is upright is a good thing. That would be easiest to design with symmetric foils.
  10. I've seen them referred to as the "Collins Keel." I never would have guessed that something like the tandem keel would work at all, but the tank testing suggested it was good enough to try in 12 Meters. It was not successful there, though. Meter boats would have to be considered a restricted draft case, so I doubt anyone thought the tandem would be better than a deep keel.
  11. If you are talking about the regular wing keel and not the tandem keel, Greeley and Cross-Whiter discuss that in the SNAME paper I posted back at the beginning. Getting that flow right is one to the keys to success. The supply this helpful graphic. Note that the downward force on the port (lee side) wing is greater than the force on the starboard wing. I imagine the imbalance is caused by the differences in flow, pressure, etc that cause the vortex off the tip of a normal keel. No, I don't know what the Trefftz plane is.
  12. As the owner of a boat that does not point high, I would advise starting a bit further down the line. Starting at the boat is going to mean either someone is going to luff you to a stop or you are going to have to bail out on port tack whether you want to or not. It's an untenable position. The other guy called "barging" because he was annoyed that you were in his way. If you were clear ahead when you passed the boat, you weren't barging (which word is not in the RRS, I believe.) However, as discussed at length above, you may have needed to hold higher after he gained an overlap to leeward.
  13. Let's go step by step... 1400 lb cast iron at 491lb/cu ft is 1400/491 = 2.85 cu ft, 2.85 cu ft of seawater at 64 lb/cu ft = 2.85* 64 = 169 lbs. Hard to know what the righting arm would be. Beam is just less than 8 1/2 feet.
  14. On the high AR keels, I agree, though I don't think the effect is negligible. OTOH, a Westerly Centaur will pop a keel out at a lower angle of heel and with more volume.
  15. On the Bolger Chebacco, the consensus is to cut the mizzen completely flat and use it only for balance, not for drive.