CNC Plans not Included

Jorge- i cant handle that file, its too complex with over 1200 surfaces... theres a problem with some of the circular surfaces on your toilets, some of the points are at infinity and its crashing the software. can you export just the main structural surfaces? You can leave it in 3dm format also...

 

I figured that might be a problem, try these, it's only the single surface geometry, of the main structure, hulls, decks and roof, left the bulkheads out as they are all extrusions. I put both IGS and 3dm. On export it opted to convert inches to microns, just so you know.

 

Here you go jorge, hydrostatics for your hulls;


Your not going to displace 15 tonnes if shes built light - how light we dont know until your design gets along further.
Another thing worth noting is that the prismatic coefficient Cp is a bit low. A low number here will result in less pitch dampening so this should be increased somewhat. This can be done by flattening out the rocker a bit - but then youll need to see what happens to the Cb which may end up too far aft.

Can rhino give you a table of all your surface areas? You can use this to arrive at a rough hull shell weight estimate.
By quickly running through the surfaces i have from your model, you have roughly double the surface area of the open source 50ft boat meaning its roughly double the weight, double the cost and double the labour. I know you wouldnt think so - but thats how boats work out A 60ft cat is a huge project - just ask anyone who has worked on building one...

 

That sounds like a tricky balancing act! I do have plenty of rocker, I want to shift it aft a bit and lessen it like Grainger does but I think I really need the NA to work on that. Which software do you use to get that info?

... So if the software doesn't calculate surface area, how does it come up with those numbers, do you tell it how much it will be submerged? Im thinking it will come in more like 12 tons ... which means I will probably be floating high. Def have to figure this out, I will modify the hull shape, think I can do that without ruining everything I have drawn though Rhino is not great in that respect.

Yes, I can select surfaces and Rhino will output the surface area, I will do that when I get back to Miami, spending tomorrow in the keys painting my house

 

Yes you just define the DWL and it calculates the volume below that line by slicing the hull up into many (50 in this case) cross sections and averaging the areas of those. It works out the coefficients based on the shapes of those sections and their respective longitudinal position.

 

Groper, can you do the Hydrostatics once more, I squeezed my design, hulls are slimmer, reduced rocker and moved it aft like Graingers. Here is the Iges file. I also checked area. It's 87.628 Sq Meters for one hull. That doesn't include the top deck, just the one hull. Thanks

 

no worries.

Once you have all your structural panels only - get a table of surface areas togeather. We then apply a panel density and thickness and will have a pretty good idea of shell weight. You then add all the bolt on stuff and fit out equipment, and youll get a pretty good idea of lightship displacement.

 

here you go Jorge.



You will end up chasing your tail on this if you cant see whats happening as your making changes. But as we suspected, your LCB is too far aft now and the prismatic is still quite low - you need more volume up forward.
Honestly, if your taking this to a naval architect, they will sort all this for you and due to your design not changing above the false floor level, its not really important for you and working out your general arrangement- all you need to do is work out how much volume you need in your hulls to fit in your desired accommodation. The more volume you have - the less performance oriented the design will be as it will get heavier and have more windage with increasing volume. Its always a trade off between volume and performance.

 

Damn, I thought I had it! Anyway I like the slimmer look and new sheer, hope they can keep it looking like this.

 

why not just buy the Grainger flying fish 60 plans and be done with it?
Tony will surely give you the CNC plans so you can build it as you wish for the appropriate fee?

 

He does provide the CNC plans. Would be cool if he would make the changes to accommodate my layout and Solar Roof however at that point I think he would be designing a completely different boat. Still I will ask him about it. Working on yours right now, good practice for me.

 

About 515 sq meters of area. Not bad!! I will make a table of all the different areas so I can get an approximation of glass, resin and total weight. In these pics I changed a few things,

1. Now it's a single layer bridgedeck, I dropped the interior floor 4 inches which let me drop everything else/
2. Gave more volume to hulls in front because can't resist chasing my tail and I narrowed the hulls aft, it's pretty close to 4' waterline now.
3. Added the support structure for the unstayed mast.

 

515m^2... does that include all the internal frames, bulkheads, floors etc?

Do you not plan to have a fore sail? If you do plan on having one - forget the unstayed mast idea, you cant get enough tension in the forestay for the foresail to work properly.

If you dont have a head sail - you will not have much sail area (power) compared to a boat that does carry fore sails.
Also - if you dont have a foresail, you will need to move the mast further forward as the center of effort is too far aft where you have it now. The center of area of the main sail would ideally need to be close to midship which pushes your mast several meters forward of where it is now... compare to this for example;

twin masts and sails to get sufficient sail area. Masts forward in the hulls to get center of effort in a favourable location. Downside is lost space in the hulls...
Chasing your tail yet?

 

It will probably come to 550 meters when I am done but that will include almost ALL fitout

Twin masts are going to cast more shade and take more room as you say. I am thinking a balestron rig will be perfect. This boat won't be a full on racer like yours but she should be pretty quick, she should be light, long and slender, about 1:15 , giving room to expand hulls if the NA needs to. Any innovations I can add to improve upwind performance will be opted for ))

I am not going to chase the tail beyond this, at least I know my fitout fits. My beam is automatically reduced as well because I have less flair in the hulls but that will be up to the NA, it doesn't affect my fitout at all.

The way I see it, I have a boat, that once popped out of the mold, will be extremely easy to fitout and rig. She will be relatively maint free when you consider the unstayed mast, micanti anti-foul, raised elec. outboards and direct drive steering.

She will be extremely easy to sail, require MUCH less rigging, I can cook, clean, do yoga etc and the boat will hum along on it's own very efficiently and I will never ever need to bring fuel on board. ... Now that is what I call a cool boat!!!!!!!

And I have three people very interested already ))

 

What my hulls used to be compared to now, much fuller in the ends, less rocker, rocker moved aft as Grainger does.