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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.  

atg

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About atg

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  1. DC Designs

    Probably want to upsize those wire blocks. I think 1.5" were the smallest ones that did not eat themselves. Bill Beaver lost his rig that way on Arrested Development at 1996 worlds. Julian Bethwaite came cruising through the dinghy park early in the regatta, had one look at his 1" wire blocks and said "Oh - that will never hold." Bill had done the math, and was sure it would hold. Sure enough, it didn't. No one came to get him after the rig failure, because a storm had wiped out the whole fleet, so he managed to restep the mast on the water with a bit of string on the end of the shroud, and got back that way. A size up is cheap insurance.
  2. IC needs ride

    Talk to Rick Peters, but he will want some money. His buddy Caj hauled Clockwork up to Montana from here.
  3. Foiling Moth Setup

    Nige Oswald - Friday Harbor Chris Maas - some other island out there near Nige Andy Mills - Vancouver BC Dalton Bergan - what doesn't that guy sail? May have sold his boat awhile back though. There are some others.
  4. what is it?

    Most excellent build. The big issue with twin main foils as I see it is induced drag at takeoff. You really want maximum span there. With two foils you get two more tip vortices than needed, and much more drag when you can least afford it. The strut drag is significant, but with two struts the main foil can be so much higher aspect that it outweighs the loss from the struts, and the struts can be much smaller also. I suspect we may see twin strut moths at some point with the Clive system if the fairing drag can be worked out.
  5. New IC sailor

    Sorry about that. That carriage was a bit of a compromise between Gaudi-esque style, reduce/reuse/recycle, and death needles.
  6. The Transat 2016

    If Riou really lost some important sails just after the start, the new foiler must really be a dog to have only finished 30 miles ahead. Those foils look like they have a ton of induced drag. Avg speed was 12 knots, which is not where you want to be trying to lift a keel boat onto foils. I'd say PRB is looking quite strong for the Vendee.
  7. Bieker-53

    Opinions are like noses. The internet is a giant relief valve so people without the 3.5 large can feel like we are important, too. I matter, dammit! Kind of a genius move by Darpa, from a Marxian standpoint. There are so many more boring things to spend that kind of coin on. It takes some balls to put the details here for everyone to carp at. Say thanks and nice boat, or move on.
  8. ...IC kit...'machete'...'

    Yes if you are inclined to join the fun and like to make stuff this is a nice way to dive in. There is no cheaper way to get a reliable, proven product. If you are a genius NA or boatbuilder then great, but most folks aren't. This kit is for the rest of us.
  9. Team Vestas grounded

    Seems to me if they had turned and tried to go upwind they would have grounded out the keel and boards and ended up sinking in deeper water. In that sense it was better to run full tilt up on the reef after the first bang.
  10. Best "Not a Truck" tow vehicle

    Yeah, you want the tow vehicle to weigh almost as much as what it is towing. No way a VW or anything like it would be safe. Dude a VW touareg TDI is over 5,000 lb. It tows 6,500lb of RIB and trailer without a problem. You need trailer brakes for any serious weight anyway.
  11. Flying Cherubs

    Ah - yes I went quite oversized on the control line and blocks also, to reduce stretch. I think I am running 1/8" spectra at the moment and the blocks are all sized at least 8x line diameter to reduce any friction losses. I recall being startled by the center of lift calculation at high speeds as well. Way behind the foil. It gives me a bit more responsiveness at high speeds, which is fine because my wand loading is a bit light at low speeds. We don't get much breeze in winter but I will try to get out and get a bit of video. Beers, Karl
  12. Flying Cherubs

    Phil and Clive - Thinking about the tailplane, is it actually true that Cl remains constant? I don't think so. As you speed up, yes, Cl needs to go down to keep the foil in the water. But this is precisely what a tailplane does - it is generating more lift with speed, and in Clive's system would therefore reduce the AOA of the mainfoil with increasing speed. This could, if the tailplane is sized correctly and at the proper angle, keep total lift constant - not coefficient of lift - with increasing speed. The tailplane is small in both area and span, and as speed increases it becomes more powerful and tilts the foil more. So adjustment for speed through the water would be automatic. Adjustment for the ride height would not. The wand could drive the tailplane to adjust for ride height, if someone were clever enough to make this work. Personally I think I would do this with rotating shafts and bevel gears. It sounds like a bit of a nightmare, but doable. What say you? Karl
  13. DC Designs

    Bummer dudes. Glad you are OK. It puts the old "journey not the destination" idea of boatbuilding to the test. I always figured I would send mine forward off the roof rack in a hard stop or accident, but somehow never did. And getting rear ended always seemed like a good possibility. Maybe LED bike flashers on the tack fitting? Sorry you missed the regatta. Nothing like long island sound in October. Who are the builders? Oliver? K
  14. Flying Cherubs

    Oh I just saw the photos you posted Clive. For some reason they would not appear before. Interesting that with totally different systems we both had problems with too much wand loading at takeoff! With an extra set of hands you can do a lot about that though. I thought of having a bicycle brake handle on the tiller to pull and get a bit more daggerboard rake for takeoff, then release once flying. Hydraulic or cable. You could do the same to somehow push harder on the rod at takeoff. It has to be convenient wherever you are in the boat while taking off; moving around to adjust it is slow out of tacks and the competition will be long gone if it takes any time to sort out at all. Seems like the joint between uprights and the foil could actually be rather fair when optimized. Decavitator used two uprights on the main foil for the reasons you describe, so you are in good company there I think. All this has me motivated to try to get out more often. My wife works weekends so it isn't always an option, but that should change for the better shortly. Good Sailing, Karl
  15. Flying Cherubs

    Yes many smart people have looked at the problem. And some dumber ones like me. On the flapped vs flapless front Phil has made a good articulation of the pros and cons. Nonetheless if one actually runs the numbers, the flap does not come out ahead of a flapless foil. Flapless allows pushing the structural limits harder, getting more span for a given thickness, and also playing with geometry e.g. anhedral. So the drag you might pick up at takeoff due to a thin nosed 2D foil section is offset, because the foil area can be smaller and the span larger, thereby cutting induced drag considerably. So takeoff drag can remain the same, while high speed drag goes down because the foil area is smaller. Flapless cleans up the T. This comes at the expense of wand load; the paddle does generate a fair bit of resistance unless the entire system is optimized to eliminate both wand loads and friction loads. I think my current system is pretty close in performance actually to a flapped foil. If there is ever another local regatta I will test the theory. It could be a bit lighter, but for a prototype it is OK. After that I should really fire up the router and make an optimized mainfoil mold, as my current foil is bigger than it has to be. I think Clive's boat demonstrates that the world of ideas is far from exhausted when it comes to wand-driven foiling solutions. They may not be easy to dream up, but neither was the flap system. In fact the more I did with my stuff the more respect I had for John Ilett and company. Lots of people have tweaked control systems on the water, but not many have developed entirely new ones. So hat's off Clive. Keep us posted. I agree it would be much more fun with a kid in the boat to share the experience, but right now we are working on swimming lessons, so it is a bit premature! Perhaps my next tilting foil will go into a Cherub hull. K