Open Source 13-15m Catamaran Plans

[archie1492]

Dear all,

I want to create a detailed building information model for a 13 - 15 meter catamaran that is capable of being CNC cut and assembled. I need some help finding plans I can use as a basis of design. Specifically, I need the hull profile information. Section cuts through the hull will give me the ideal contours for a boat of this size. Can someone help? After weeks of searching, I still cannot find these online.

For now, this is merely an exercise in my 3d modeling capability. I'd like to share my drawing work with the forum if I can get some assistance to start off.

There are future possibilities I am also considering. I'm an experienced Architect & construction designer with a strong background in computer aided design. Once I've modeled the boat in 3d, I would like to flatten the various parts and create plans for the individual boat parts to be CNC cut. I would like to build a small scale model first (1:2o or perhaps 1:10) with the ultimate goal of building the boat full scale.

 

[TANSL]

This is a very simple catamaran which, if you are interested, I can give you a lot of information. It is not a spectacular boat but it can help you in your first steps with boats. LOA = 16 m, Lbp = 14.6 m

 

[archie1492]

Thanks I really appreciate it. The hull lines for the motor cat you've provided are not quite what i'm looking for. I'm specifically looking for the hull lines for a 14m catamaran sail boat. I guess there is some standard for these contours especially the area below the waterline. Check the attached document as well if anyone is interested in this.

 

[TANSL]

I'm sorry, you never specified that it was a sailing catamaran. I thought that to carry out your purposes, "For now, this is merely an exercise in my 3d modeling capability", any model was valid. Apparently, you have different purposes than, in addition to, to practice with 3D models.
The better you clarify what you are really looking for, the better someone can help you.

 

[archie1492]

Hi all,
Here's an example of what kind of information I need to get started.

Optimising Hull Lines for Performance https://www.graingerdesigns.net/the-lab/optimising-hull-lines-for-performance/

The boat shown here is a 8.5m cat sailboat. I'm looking for something a bit larger in the 14m range. Also, the images only show one of the hull profiles. I'd like profile lines for the entire boat. I will post some other images I've found online showing profile lines for smaller boats. I still cannot find any 14m hull lines. Can anyone help?

 

[archie1492]

Here are some other hull lines I've found online. Hope this is useful to anyone else looking for this information. Thanks!

 

[TANSL]

You could take any of those boats and scaleb the lines to get the desired length. Since it is only a 3D modeling exercise, you do not have to worry about anything else.
You could even make a mix of 2 or 3 of those models to get the one you are looking for.

 

[archie1492]

Thanks Tansl, I'd like to make the boat drawings accurate for the 14m size. Perhaps one day I will develop this into something worth building full scale. The more accurate I can draw the boat, the more I will learn about the boat design.

 

[TANSL]

Maybe it does not look like it but I would like to help you. If you do not find what you want on the Internet I could draw a lines plan, strictly following your instructions, which would help you to make the 3D model. Or, if you find something similar on the internet I can adapt it to your needs and fill in the information that you indicate you need for your work.
I insist that starting from the shapes of a 10 m boat you can get the shapes of a boat of 14 m, with total accuracy.

 

[Dolfiman]

I'd like to make the boat drawings accurate for the 14m size. Perhaps one day I will develop this into something worth building full scale. The more accurate I can draw the boat, the more I will learn about the boat design.

I can propose you the spreadsheet application Gene-Hull attached, hull generation for early stage project. I have just finalised a version dedicated for hull of catamaran and took your spec. for a first test :
Loa 14,00 m ; Lwl 12,75 m ; B 1,80 m ; Draft 0,75 m (at 38 % Lwl ) ; ....

>>> Cp 0,59 ; LCB : 44,95 % Lwl ; Sw (2 hulls) : 43,92 m2

; Displacement (2 hulls) : 13 800 kg ; ....​

​

(For the displacement 13,8 t, I took the example of the Catamaran Saona 47 by Fountaine Pajot
Sailing catamaran - Saona 47 - Fountaine Pajot http://www.catamarans-fountaine-pajot.com/en/sailing-catamarans/catamaran-saona-47-2/ )

The attached application (.ods file developed Under Open Office 4.0.1) has the corresponding input in place. From this first set of data and with the help of the User guide also attached, you can shape the hull according to your objectives, hydrostatics data and ratios usually considered by naval architect. Produced data allow to continue the project with a 3D modeller (for that option, all necessary data are provided in section 5.) and/or to draw sections for the building of a scale model (necessary data are provided in section 6.).

Note that the application cannot deal with hard chines generation, By hoping this can be helpful,

 

[archie1492]

Dolfiman, thanks so much! This is exactly what I was looking for. It's very interesting and probably a bit over my head at this point. I think this should work for modeling the basic hull shape. For the bridge deck and all of the stuff above the hull I can model this with a bit more creativity. Although, I'd like to learn more about understanding the center of gravity for the boat and the proper location of the mast. Are there any rules of thumb about this?

Thanks again!

 

[Dolfiman]

I think this should work for modeling the basic hull shape.

Yes, it is the goal of Gene-Hull, a light flexible tool to shape a hull through numerous fast iterations on either the geometry or the parameters, and with all hydrostatics data updated at each step to help converge, and then , once converged, to turn to the 3D tool. At first, I recommend you to "play" with each parameter or geometry without preconceived ideas, just to see the effect on the linesplan and the output data, it is both fun and informative. And in a second step, you can more seriously try to converge towards a good hull.

For example, here is another slightly different version of the hull, with new input data (with a better LwL/Bwl without changing the wetted surface), stored "V2" in the Hulls storage sheet, put side to the "V1" version previously transmitted.

Although, I'd like to learn more about understanding the center of gravity for the boat and the proper location of the mast. Are there any rules of thumb about this?

As regard the center of gravity, it results from the inventory and distribution of all the masses, the laborious part of a project, and of course should coincide with the center of buoyancy (in longitudinal, Xc in the application).
As regard the mast position, and more globally the sailplan position with regard to the center of lateral resistance, I am myself not experienced in multihulls, it is not mentioned in the excellent Terho Halme paper, likely that someone in this forum can give you (and me) information.

 

[Dolfiman]

In complement to illustrate this first approach, my good friend Alain did some 3D views here attached of the hull V2 version with Multisurf (using fit for purpose ouput data in section 5. of the above file).

To inspire you

, some other examples of cata, more sport/day sailer oriented than the Saona 47 :
- R/P 45 (Reichel-Pugh) : multihull http://reichel-pugh.com/tag/multihull/
- Dazcat 1295 : in this video, from 1:45 the launch, you can see the hulls from various angles
https://www.youtube.com/watch?v=0BZF4Udda5E

- SIG 45 (VPLP design) : from 1:20 you can see the winward hull fully lifted​

 

[dean 1962]

Dear all,

I want to create a detailed building information model for a 13 - 15 meter catamaran that is capable of being CNC cut and assembled. I need some help finding plans I can use as a basis of design. Specifically, I need the hull profile information. Section cuts through the hull will give me the ideal contours for a boat of this size. Can someone help? After weeks of searching, I still cannot find these online.

For now, this is merely an exercise in my 3d modeling capability. I'd like to share my drawing work with the forum if I can get some assistance to start off.

There are future possibilities I am also considering. I'm an experienced Architect & construction designer with a strong background in computer aided design. Once I've modeled the boat in 3d, I would like to flatten the various parts and create plans for the individual boat parts to be CNC cut. I would like to build a small scale model first (1:2o or perhaps 1:10) with the ultimate goal of building the boat full scale.

 

[dean 1962]

Archie, I have been looking to do the same thing. Where are you at on the project? Very interested in hearing all about it. Thanks.