4.50m Sailing Yacht Concept

Thanks very much for that. Do you have a suggestion for a program I could use to fiddle about with this myself and maybe to do a full 180 degree test with the cabin?

JAL

 

There are several programs, very good and expensive. I like a lot MaxSurf, I use it often, but mostly use my own application, ARQN, which needs AutoCAD to create the model and draw and print curves and results.

 

I don't think I can really justify the expense of one of these programs. Could you please find out how low I need to get the COG for the boat to recover from a full 90 degree knockdown? or, if you can, set the crew weight so that it is on one side of the centreline as if hiking? I think this would make a big difference and be helpful in working out levers etc. for the rigging. I hope this is not too much trouble.

 

It would help you to make a first estimate of the lightship and the position of its center of gravity. Mine am convinced that it is not too correct, although it was pessimistic.
It would also be helpful to have the body lines plan of the ship.

 

What do you mean by body lines plan?

 

A drawing with, clearly defined, the contours of the frames, the longitudinal profile in bow and stern, the line of the deck at side and center line, some water lines. Apart, of course whether the pantoque is the curved or straight.
If you have an ".igs" file of the model it would be enough.

 

Would an autocad file of the hull net be ok?

 

Here is a .dxf . Maybe this will be easier than using a lines plan for you?

 

Yes, I just need now deck and deckhouse.

 

Here you are. Thanks.

 

Are you able to do anything with this?

JAL

 

Yes, I'm working with the 3D model.

 

Thanks very much. Hope it goes well.

 

Please, observe and compare the stability curves of your boat with a normal sailboat. Your curves are very poor. The righting arm of your ship becomes negative at approximately 77º. This, for a sailboat, is a very low value.

 

I see. It seems to have more dinghy-like characteristics.. I'm not certain but I think the COG may be lower because of the bulb keel so I will do some better estimates on this. It was surprising to see the max. GZ change so much with the passengers to one side. Thanks for the help- I will try and design a more forgiving boat..