Feather Transverse Flex w/ Maxsurf

[Yacht Skipper]

Is it possible to feather the transverse Flex with maxsurf in order to start with round bilge at the bow and end up with hard chines toward the stern.
How is there any other ways to do this ?

Thanks

[bhnautika]

YS you can get a chine at the stern by compacting a number of points into one and adjusting the weighting and stiffness.

[Yacht Skipper]

Thanks, I'll give it a try.
I'm new to CAD and it seems that I will never finish to learn...

[Yacht Skipper]

Hey Nautika, I really tried several times, but end up with something impossible to fair and the chines were not sharp at all.
Any tutorials on how to do it ?
Or is there a software outthere where I could set a different transverse flex for each sections ?

Thanks

[bhnautika]

YS is this the sort of thing your after?

[bhnautika]

YS Just another thought, you could also bond two or more surfaces with the same longitudinal stiffness but different transverse. Then do a mix of different methods

[Yacht Skipper]

Thanks for your help Nautika, I really appreciate.
What I'm trying to accomplish is something like the attachment.
How would you do it ?

[Andrew Mason]

The key to compacting points to form chines or knuckles is to use the right number - the higher the order of the surface (i.e. the stiffer) in the transverse direction, the more points you need.

The rule is that the number of control points you need to compact is one less than the order. So an order 4 surface needs 3 control points compacted together, an order 6 surface needs 5 control points compacted together.

As you need to spread the control points out in a fair manner to fade out the chine, the less points you have the better, so order 3 or order 4 is recommended for this sort of hull shape. Note that this does not stop you using high order splines longitudinally to get the best longitudinal fairness, I would still recommend order 6 or above in that direction.

[bhnautika]

YS As Andrew pointed out the number of points to stiffness helps to smooth out the lines. I might suggest that a few extra points and stiffness may help the process, on smoothing the transition from flat panel chines at the stern to round bilge at the bow. The extra points help the transverse curvature lead into and out of the chine. I did a quick example of what I mean to roughly your idea.

[Yacht Skipper]

Thanks gents,

I got the idea, now I just have to practice a bit as my first attempt wasn't very succesful

[Mikey]

Maxsurf has a limit of 25 rows and 135 columns. I think that it is possible to "trick" Maxsurf to accept more than 25 rows by transpose columns and rows. Should be enough for almost anything.
Mikey