Where to get laminate drawing help for catamaran build? NA or Composite Engineer?

Would like to put out the question of where my best options are to find help with laminate drawings and schedule for catamaran build. After speaking with a few NA it seems that most have a composite engineer work on this part for them. Is that correct? If so, would it be advisable to look for help from an NA or an engineer instead?
I am working on getting all the info together for a 52 ft coastal catamaran project that is to be built using epoxy wet hand layup over male plug using 3/4 divinycell or 3/4 core cell and glass/ carbon reinforcement.
Max load 22,000 lbs.

Looking for help to have the laminate drawings and schedule completed.
Just curious if others have used the engineering services of the core provider as they are readily available and willing to help especially for someone placing a substantial order. Thoughts?

Thank you
Ismotorsport@yahoo.com

 

why 3 threads for the same questions mate?

youve done a back of napkin design yourself havnt you?

you havnt involved a naval architect yet have you? or if you have, youve had a falling out, probably over money, and you basically have nothing more than something like a study plan, havnt you?

Now you need the engineering done so you can work out the build, dont you?

Just say it like it is, and you would have got some more useful information... going about it like you have, youll get nothing...

 

Groper,
If you send me a pm or email me will be happy to share what I got so far. Would love to hear your thoughts after you have seen something rather than some guessing or stipulation... I am going about the project in an unorthodox fashion though... That I am guilty of, doesn't mean I deserve any less help. In fact if I had paid the big bucks for a big firm to take on my project I probably wouldn't be here asking for info and advice... Would I mate?

 

when you respond on the forum, click "go advanced".

Then in the advanced reply diaplogue, you will see an option to attach a file, the icon for this is a paperclip.

Browse your computer to the file containing "what you have" and attach it to your next post.

Everyone can see what youve got, some may choose to help, some here may offer their professional services or others simply opinions or advice...

 

incomplete IMG of project for review and advice



[/IMG]

some IMG files that show the design with structural bulkheads (minus stringers)

 

Depends upon the experience and technical/structural ability of the NA and if the composite material is new to them.

So, as Groper says, either you have a design already done (that is what you're implying by posting those values) and you just want someone to "give a lay-up", or you have just a basic concept, no idea whether it shall work and need a NA to see if it will work and then see structural what is or is not possible.

You need to decide which way you are heading since you wont get much of a reply from the above meager posting/info.

PS...you just posted those images as I replied.
I can see those are just pretty pictures done in a standard 3D modelling software. Do you have any real hard data other than pictures of a 'dream'/idea?

 

not shown are the transom hung rudders for twin tiller steering, deck layout, updated cabin top, daggerboards, etc.

 

Where does the 3/4" core specification come from?

 

Condition Summary

Load Condition Parameters
Condition Weight / Sinkage LCG / Trim TCG / Heel VCG (in)
Condition 1 4988.000 kgf 0.000 deg 0.000 deg 0


Resulting Model Attitude and Hydrostatic Properties
Condition Sinkage (in) Heel(deg) Trim(deg) Ax(m^2)
Condition 1 -4.011 0.000 0.000 0.62


Condition Displacement(kgf) LCB(in) TCB(in) VCB(in) Wet Area (m^2)
Condition 1 4988.003 352.861 0.000 -11.715 20.405


Condition Awp(m^2) LCF(in) TCF(in) VCF(in)
Condition 1 16.067 351.488 0.000 -4.011


Condition BMt(in) BMl(in) GMt(in) GMl(in)
Condition 1 18.444 1551.094 6.73 1539.38


Condition Cb Cp Cwp Cx Cws Cvp
Condition 1 0.386 0.543 0.726 0.711 2.437 0.532

 

Analysis Type FreeFloatEquilibrium

Surface Meshing Parameters

Density 1 Minimum edge length 0.00000254 in
Maximum angle 0 Maximum edge length 0 in
Maximum aspect ratio 0 Max distance, edge to surf. 0 in
Minimum initial grid quads 0 Jagged seams False
Refine mesh True Simple planes True


Load Condition Parameters

Weight 4988.000 kgf
Model Trim 0.000 deg
Model Heel 0.000 deg
VCG 0 in
Fluid Type Seawater
Fluid Density 1025.900 kg/m^3
Mirror Geometry False


Resultant Model Attitude

Heel Angle 0.000 deg Sinkage -4.011
in
Trim Angle 0.000 deg


Overall Dimensions

Length Overall, LOA 622.819 in Loa / Boa 7.616
Beam Overall, Boa 81.778 in Boa / D 0.767
Depth Overall, D 106.643 in


Waterline Dimensions

Waterline Length, Lwl 567.641 in Lwl / Bwl 9.390
Waterline Beam, Bwl 60.453 in Bwl / T 2.702
Navigational Draft, T 22.376 in D / T 4.766


Volumetric Values

Displacement 4988.003 kgf Displ-Length Ratio 46.380
Volume 4.862 m^3
LCB 352.861 in FB/Lwl 0.566 AB/Lwl 0.434
TCB 0.000 in TCB / Bwl 0.000
VCB -11.715 in
Wetted Surface Area 20.405 m^2
Moment To Trim 343.583 kgf-m/in


Waterplane Values

Waterplane Area, Awp 16.067 m^2
LCF 351.488 in FF/Lwl 0.563 AF/Lwl 0.437
TCF 0.000 in TCF / Lwl 0.000
Weight To Immerse 418.683 kgf/in


Sectional Parameters

Ax 0.621 m^2
Ax Location 373.125 in Ax Location / Lwl 0.601


Hull Form Coefficients

Cb 0.386 Cx 0.711
Cp 0.543 Cwp 0.726
Cvp 0.532 Cws 2.437


Static Stability Parameters

I(transverse) 2.278 m^4 I(longitudinal) 191.555 m^4
BMt 18.444 in BMl 1551.094 in
GMt 6.73 in GMl 1539.38 in
Mt 18.248 in Ml 1550.898 in



Location (in) Immersed Area (m^2) Immersed Girth (in)
13.054 0.000 0.000
82.257 0.037 20.259
151.459 0.172 42.634
220.661 0.355 60.493
289.863 0.525 73.096
359.066 0.618 79.263
428.268 0.579 77.432
497.470 0.388 65.886
566.672 0.106 41.576

 

So someone modeled this boat, then gave you all these parameters the software spit out? I hope you got more than that, such as the beam scantlings. Where are those? Are the beam scantlings part of what you are trying to figure out right now?

It looks like someone was just playing with software here.

 

We were discussing scantlings using 3/4 divinycell h80 and h100 and 17oz and 12oz double bias, 17oz and 12oz biaxial, and 17oz uni and also working on laminate drawings when NA took another $$$ project .... Money talks, poor guys with dreams walk? And end up on forums...

 

All jokes aside... We got that far and I was looking for assistance to continue with engineering (laminate drawings) so I can actually keep on schedule. Otherwise I have to wait till other project is completed and would like to begin this year.

 

For that to work, you need to calculate all the weights of the interior equipment too. It is tedious and slow but not particularly difficult. Those numbers don't help much for structural calculations. There is a lot of garbage, for example "fluid type seawater". It sounds technical but is irrelevant. You should post a set of lines, in standard three views, with bulkheads, stringers and other reinforcements indicated. However, if what you posted is all you have, the boat needs to be designed completely. Particularly since you say you want a performance boat.

 

Ok, so what it looks like from here (and it's good that you shared) is that the boat was in a preliminary design stage.

He modeled it, then spit out the parameters from the software, then left you stranded.

That really sucks. Sorry to hear about that. Now I also see why you are trying to find a way to pick the process up again from where you left off.

That guy really left you in the lurch.

Unfortunately, about all you can do at this point is ask for the files from the 3-D modeling, since you paid for them - and go to another designer to start over.

Or... since it looks like the NA didn't really do much work yet, you can just go to another designer with everything you have already figured out and start fresh. That's probably the best thing to do.

It's unfortunate, but a project of this scale can't really be "crowd sourced" on a forum. It would take you 10 years just to sort out everyone's different opinions on things.

You really need to hire another designer that can take the project to completion (will cost as much or more than you already spent for this small amount of work). Or... just buy a stock set of plans that closely matches this.

Does Morelli and Melvin sell stock sets? This boat looks a lot like one of theirs. If not, there are many reputable catamaran designers that have stock plans that will even tweak them just a touch for you.

I'd go that route.

You are looking at a $300K build cost here. Minimum. If you spend $20K on a design, you are doing yourself a huge favor. What you have isn't really a design. It's more of a modeling and some crapy software data spit out. The real work is yet to come on this design. The rig needs to be part of the design process. The beams need to be defined (and laminate schedules done). The bridgedeck schedule needs to be done. Yes, many boats this size are made from 3/4" core cell, but you don't even have the beam design or chainplates. That's the most important part.