Lcg

Discussion in 'Boat Design' started by Akgramps, Oct 11, 2008.

  1. Akgramps
    Joined: Aug 2008
    Posts: 34
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Alaska

    Akgramps Junior Member

    Can anyone explain how to detrmine the Longitudinal center of gravity (LCG) on a particular boat?
    Thanks
     
    Akgramps, Oct 11, 2008
    #1
  2. Guest625101138

    Guest625101138 Previous Member

    Make a 4 column table listing all of the components and pieces that go together to make the boat listing their individual weight and distance from the stern.

    In a fourth column multiply the weight by the distance to get moments. Add up all the weights to get total weight and add up all the moments to get total moment. Now divide the total moment by the total weight. The answer is the distance of the LCG from the stern.

    If the boat is already built and in the water you can do a simpler exercise by determining the change in pitch with a change in weight distribution and calculating from that information.

    Rick W
     
    Guest625101138, Oct 11, 2008
    #2
  3. Akgramps
    Joined: Aug 2008
    Posts: 34
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Alaska

    Akgramps Junior Member

    Rick,
    Thanks for the reply and info, Yeah this boat is done. It is a 20 foot aluminum riverboat with a warped hull and is very sensitive to bow steering. I have modified the top of the tunnel, it was angling down and acting like abig trim tab, pushing the bow down. Angling it up slightly has made an immense improvement.
    I think it can be better, I have read warped hulls are more senistive to LCG as they tend to have flatter trim and more wetted surface. Hence the question about LCG. I am thinking thats not so impotant now as I can always adjust the load if the boat is loaded heavy.
    I want to add some lifting dtarkes and have a design in mind, dont know if its right? and dont know if I should run them all the way to the transom?
     
    Akgramps, Oct 11, 2008
    #3
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.