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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 lohring

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  1. Meade Gougeon has passed

    I am very sad to hear this news. I met Meade at the 1969 North American Multihull Championships. I still have a signed first edition of Gougeon Brothers on Boat Construction that has influenced my boat building ever since. He was involved not only with boat building but also with early wind turbine blades. I remember his telling of pricing some test wood/epoxy blades for NASA. He estimated a price for a pair and then doubled it for safety. NASA assumed it was the price for one blade and doubled it again. The blades ran successfully on a large turbine in Hawaii. His innovative style will be missed. Lohring Miller
  2. Smyth Wingsail via Jim Brown

    The Hubbard designed hulls are upside down on the trailer. Lohring Miller
  3. Smyth Wingsail via Jim Brown

    1972 C class Mountain Lion. There's nothing really new under the sun. Lohring Miller
  4. Congratulations Mead Gougeon

    I first met Mead in 1969 at the North American Multihull Championships. His tri (Victor T at 6:26 in the video) was state of the art then and his little tri obviously still is. Lohring Miller
  5. Congratulations on your win. You are still an inspiration to us younger (74) sailors. Lohring Miller
  6. best tv series... possibly ever?

    I can't believe no one mentioned the Simpsons. Here pictured dining out in the real Springfield (Oregon). Lohring Miller
  7. Kite/dinghy thingy...I dunno........

    Winch controlled kite sailing is being developed by these guys. Simpler systems are available from Wingit. My favorite simple concept is the . Lohring Miller Kite boat K-1 Kite Scooter
  8. Radio Control Multihulls

    You can actually use off the shelf hardware for RC sailboats. I think the Eagle Tree stabilizer (http://www.eagletreesystems.com/index.php?route=product/product&product_id=50) or similar controllers would be ideal for a Moth style two foil boat. Fore and aft trim would be by rudder foil angle while lateral trim could be by moveable weight. Heave height control would still be by a feeler like the full size boat. A fore and aft as well as lateral weight movement would work for conventional multihulls. If a rudder wing is used its angle could substitute for fore and aft weight movement. Lohring Miller
  9. Radio Control Multihulls

    Boat Design Net Moderator Moderator Join Date: Feb 2010 Rep: 850 Posts: 301 Location: www.boatdesign.net The initial comments which fall under personal attacks / personal insults have now been removed so as not to provoke more or derail the thread by inviting fighting from another forum over to here (if a fight starts elsewhere, please keep it there.) The forum here isn't for posting jabs about others. Hopefully this will remove the reason for further bickering. If people are not interested in a project, they can always use the ignore list or simply move on to something that does interest you. Posts which are only intended to be criticism or jab at someone would be better directed elsewhere as these don't really add anything new and only add noise. Let's please keep the threads constructive. Thanks. __________________Please be polite to all other members. Please respect those who take their time to give advice freely. And please keep threads on topic. Forum Rules
  10. Radio Control Multihulls

    The first post in that thread was 11/11/2003 by Tom Speer. The last post was 11/2/13. In between there were over 1000 posts, many by people deeply involved with making today's foilers possible, and over 200,000 views. Is there a better discussion on the evolution of hydrofoil sailboats? I do not subscribe to any other forum where the moderators would tolerate discussions of the type in this thread. On the other hand, I don't subscribe to any other forum that's being sued for allowing internet bullying. Lohring Miller
  11. Radio Control Multihulls

    Here is a great discussion of foilers. I wouldn't consider a serious design discussion in this forum because poor monitoring allows discussions to deteriorate like this one has. Lohring Miller
  12. Radio Control Multihulls

    I'm 70 years old and also built model airplanes as a teenager. I still build and race radio controlled model boats. Along the way I sailed a variety of boats including Lightnings, Thistles, Coronado 15s, and Class C catamarans. In the late 1960's I worked in the engineering department of General Dynamics Electric Boat Division. I promise that they did model testing. I've been involved with designing the . We built a model to test various ideas before committing to the full scale design. Models are a time tested way to try new things without spending lots of time and money. The complex interactions in sail boats are hard to predict, even today. If you aren't an America's Cup team with millions of dollars to spend on engineers and computer programs, models are a great, low cost method. By the way, Burt Rutan won model airplane contests as a teenager. He went on to test radical airplane concepts using a model mounted on a pickup. Take a look at the Scale Composite web site to see what a model builder can accomplish. For those of us for whom aerodynamics isn't our day job, model building is a great way to explore the science. Too bad you grew out of your curiosity and interest in exploring new ideas. Lohring Miller
  13. Radio Control Multihulls

    "If I'm honest I was expecting to see more amps!" At the time we ran the boat (2008), 20C batteries were state of the art. We could have pulled 200 amps from the batteries if we didn't care about life, but the motor was getting hot as it was. Seventy horsepower was more than this hull runs with IC engines. We were running the boat too fast for the design and it showed signs of instability. When we started the project, we only expected to run 80 mph. I have no experience with LiFe batteries since thay have lower performance for our power applications. I run lithium polymer receiver batteries and have had no problems with that gentle application. :Lohring Miller
  14. Radio Control Multihulls

    OMG! That is hugely impressive. So many questions...can you P-L-E-A-S-E post up the specs of that thing? I know lipo & brushless pretty well, so details will be appreciated As for lipo, I find them safer than NiMh This is seriously off topic,. especially in a sailing forum, but here goes. The boat is a Ron Jones outboard hydro design. Mike Bontoft built it at Ron's company, Composite Structures, Inc . Batteries were from Enerland, a Korean company. At the time their lithium polymer batteries had exceptional current capacity and very low weight. Jason Choy, their marketing director, was very helpful in getting 42 – six cell packs of their best batteries at about ½ list price. Enerland was purchased by A123 Systems during this time but they still honored their commitment to us. We arranged the batteries in six boxes connected in series with seven batteries connected in parallel in each box. Mike researched motors and found Jim Husted’s company, Hyper Torque Electric, had provided rebuilt lift truck motors for several high performance electric vehicles. Because of the outboard configuration, they decided on a relatively small, light motor that started life as a 48 volt pump motor. Though the rest of the electrical system could easily support 100 propeller horsepower, this motor was probably only good for 70 horsepower continuously during the kilo runs. Mike designed and built a quick change gear box to increase the motor output rpm to one better suited to the available racing propellers. We ran a standard outboard racing lower unit. Several other venders provided help and components during the construction period. Eagle Tree Systems gave us data loggers that provided invaluable information on the boat’s performance during its runs. Tecknowlegey furnished specialty contactors. Charging the boat’s 42 batteries was a challenge. We finally decided to charge each battery individually with Hyperion Duo chargers. RC Lipos and Rivergate Distributing helped out with the chargers and power supplies we needed. King graphics supplied all the high quality graphics. We used a Zilla 2000 amp speed control. Without the driver, the boat weighed about 500 pounds ready to run. Though our first tests were considerably above the existing APBA and UIM records, we felt there was room for improvement. We contacted multi record holder, Bob Wartinger, for help. He not only furnished setup advice, he gave us two of his record setting propellers to try. This help raised our test speeds from 80 mph to slightly over 100. Below are some pictures of the boat and graphs from the record runs. The graph shows propeller rpm and the voltage and current from one 6 cell battery pack. Lohring Miller
  15. Radio Control Multihulls

    Lithium polymer batteries are safe if you use them correctly. They are lots tougher than lead acid batteries in high power use and lighter than anything else. It doesn't make a lot of difference for radio system batteries, but the lithium polymer battery has revolutionized model power plants. My experience is mostly with RC electric boat racing, but I was involved with as well. The important things are: Use a balancing charger designed for lithium polymer batteries Don't charge at a rate higher than the battery manufacturer recommends Don't over discharge. We use speed controllers that shut off when cell voltages drop to 2.8 to 3 volts Don't draw higher currents than around 40C (40 times the packs milliamphere hour rating) for high quality batteries From the picture below you can see we weren't too worried about the batteries. The boat ran 42 - 6 cell, 5000 mah packs for a total of 252 cells. Lohring Miller