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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.  

WanderingWheel

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About WanderingWheel

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  1. adventure 40

    I work on FEA for commercial ships (and the occasional toy). FEA utilization has gone through a few evolutions in response to the market condition and the experience of previous ships. in the 1980's it was used primarily to cut the lightweight of the ship and to support the introduction of high strength materials. Unfortunately that went too far and the incorporation of fatigue analysis brought the ships back into line. In the next few decades shipyards became very competitive on price, and did everything they could to "optimize" the structure for build-ability and weight. The worst examples of these are referred to as orange ships because the entire ships looks orange in the pretty green-to-red FEA pictures -- i.e. no margin for error or unexpected circumstances. Now FEA is being used again to bring the ships back from that extreme and to a more realistic structure. The next evolution is likely to use a greater incorporation of vibration and buckling analysis to again pull steel out of the ships. The Class Rules have also been lagging behind the analysis and experience curve with the last major change initiated about 10 years ago and the results (generally positive with some complaints they went too far and others they haven't gone far enough) only starting to come in now. However, it now appears that a ship built to the minimum Class Rules is finally close to acceptable again whereas the previous Class Rules would have approved a woefully inadequate ship. As Bob notes, experience is still one of an engineers greatest assets. You have to be able to look at a structure or drawing and intuitively know if it is "right" or "wrong". When using FEA I have found it very important to know what the answer is before your start, that way you can quickly find errors in the model or can identify and investigate unexpected results. In that sense, FEA is a poor tool if you are not planning to change the structure from the standard, successful designs of the past. However it can be very powerful when designing a unique vessel, incorporating new materials, or reducing weight and cost. For yachts I agree that it is unneeded cost ad time for standard, robust designs with no unusual features, structurally speaking. Yes, racing boats are a good use of FEA, but I would argue that it is money well spent on large-run production boats as well. My goals on the production boats would be to ensure that critical areas -- keel joint, deck joint, rudder, mast step, chainplates, etc. -- are sufficiently strong, and also to reduce construction time. Any weight savings I expect would be negligible but a welcome dividend. I know that many of the large yacht design firms do currently use FEA in this manner.