Maxsurf Help

Hi, How do you guys model the parallel middle body connected to the aft and fwd portions of the hull.
Ive always did the hull in one singular surface, going from either fwd to aft or aft to fwd depending on what I feel on the day. I think this is okay for Stability Purposes, I find that the lines it produces specially the parallel middle body are not consistent. How do you guys work this out?

From what I've researched, some use 3 surfaces, 1 each for the FWD, middle and AFT portions. If that is so. How do you connect those 3, I have a hard time producing 3 surfaces which can connect? As maxsurf requires that for surfaces to join they need to have the same number of rows of control points.

My goal is to be able to produce a surface I can use for stability, and something I can use to produce lines with.

Off the top of my head, I guess I can also just export the FWD and AFT portion, then use Rhino to make the middle portion, the import the completed surface back to maxsurf. Not sure if this is the way to go though, thoughts?

 

I am not a Maxsurf user or have the program, but splitting a hull in Rhino should work.
Here is one that I did the hull in Free!Ship, trimmed and added the transom, split and lengthened with a Sweep1 and Mirror as shown in red. After joining the hull seems OK with ShowEdge.

 

Hello, the parallel middle body can be easily obtained in Maxsurf by drawing the curve of the midship section and extruding it longitudinally for the necessary distance, given that in the parallel middle body the section is constant.







In the event that you later want to join the aft body and the bow body with the parallel middle body, you should plan to use surfaces with the same number of rows of control points and the same transverse flexibility, which is not always feasible, given that many times more rows of control points and greater transverse flexibility are required on the bow and aft surfaces than on the parallel middle body, for logical reasons of the hull shapes.

In the event that you do not join the surfaces (which is often not feasible; and sometimes, even not convenient), there would be no problems with the model when using it in other Maxsurf modules, such as Maxsurf Stability, as long as the "gaps" that remain between the stern and bow surfaces with those of the parallel middle body are small enough, so that they do not substantially affect the hydrostatic calculations and that the calculation sections in Stability are generated correctly (gray sections in the screenshot below, just as an example). Remember that Maxsurf will close those small gaps with straight lines, so if they are very small, they will not substantially affect the results in the other modules.



In any case, always verify the correct configuration of the calculation sections when you use the model in the different modules (Stability, Motions, etc.), in order to validate the model for use.

I hope it has been helpful to you. If you want to learn more about Maxsurf Modeler, modeling techniques and use of basic commands, I invite you to participate in the course of which I am Instructor at Navalapp (Maxsurf Level 1; and we are currently working on level 2).

Maxsurf 1 – Navalapp https://navalapp.com/courses/maxsurf-1/