Hull framing

[Aop Aur]

I heard that the frames (made from the body plan/hull lines) is spaced equally between the aft perpendicular and forward perpendicular. But I don't remember where I got this info from. Could anyone confirm this? Also is there any other factoids about the spacing placement of these frames? Helps and suggestions will be appreciated.

Thanks!
Aop

[EJFoeth]

There are typically 21 stations along the hull (so one each L_PP/20). These have nothing to do with the actual (structural) frames of the hull. The length between perpendiculars is a bit weird. It's usually defined as the distance of the intersection of the bow with the design waterline and the center of the rudder stock (or for warships typically the intersection of the waterline with the stern), but this is not necessarily so when changes are made during the design. You can redefine Lpp of course..

[Admhawk]

In my experience, the frames are typically spaced where needed. The forward and aft frames are often closer together due to the more complex hull shape.

A typical spacing might be first frame from tip of the bow is frame 0, then 1/2, 1, 1.5,2,4,6,8,12,16,18,22,26.......,48,50,51, stern transom. There are many factors that will determine what each ship will have for spacing. It's best to go by plans if available.

As EJ states, Stations are more equal, but I have seen them vary as well. The Ticonderoga plans I was just looking at had something like fwd pp = 0, then 4', 8', 12', 16', 24', 32', 38', 42', 46', etc... varying from 4' to 8'.