the yacht design process

8/18/2019 The Yacht Design Process

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The Yacht Design Process

The following article is a summary of how a new custom yacht design is imagined,

sketched and drawn. In addition to the following notes, our Introduction web page provides an outline of our general approach to yacht design.

While seemingly complex, the design process is made up of a series of incremental steps,

much like the building process itself. The goal of undertaking the design of any new

yacht is to take a unique set of owner requirements and to turn them into the best possiblesolution to those requests. If the resulting design is to be what it should be, each of the

steps outlined below must be addressed thoroughly.

There is first the idea, and then the bringing forth of the idea into a functioning reality. Inorder to get the relevant information on the table, two primary ingredients are necessary:

I. Owner's Specification: The first design task is actually performed by the prospective

boat owner. It is first to imagine the goal, and then to create an !wners "pecification ormission statement for the proposed vessel. With that information understood, we will provide a written #esign $roposal to outline how we propose to meet the goals that have

been set forth.

• %ather than being a detailed description of the result of the design process, the

!wners "pecification is better if seen as a general guide to the intent of thedesign.

• Toward that end, ideally the owners mission statement will be kept fairly simple,

since the details of the design will emerge as a result of the design process itself.

• The basic information needed is an outline of the intended vessels si&e, layout,

materials of construction, the intended use, range, speed, rig, and generalaesthetic.

• The essential information should include the intended schedule for designing and

building the yacht.

II. Design Proposal: 'y first (ob is to understand the preliminary !wners "pecification,

then to provide the prospective client with a detailed outline for creating the new design.

This is in the form of our standard written #esign $roposal which includes the

following:

• ) written outline of the design process itself.

• ) list of the deliverable drawings and documents.• )n estimate for the design work required in order to create the design and to

detail the plans for the vessel as described.

The following paragraphs describe our design process, and outline the deliverable

drawings and documents.

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Stage I - The Preliminary Design Study

)fter our Design Proposal has been reviewed, if the prospective boat owner approves of

what we have proposed, then the actual design work can begin.

) custom design starts with listening to the requirements of my clients. The ob(ective isto create the best mutual design solution in terms of vessel type, layout, si&e and style.

'y goal is to propose an appropriate form and function to suit the vessels intended

purpose, and to follow that up with a thorough analysis of structure, stability and performance.

There will first be a series of information exchanges, possibly including clippings of

similar vessels or sketched layouts provided by the client. )fter the owners requirements

have been articulated I will usually begin by creating a preliminary *# +)# model of theintended vessel, which is most often created by adapting one or more of our existing

designs or prototype designs to its new purpose.

The *# model allows us to determine:

• The envelope available for the accommodations

• The overall si&e and hull form

• The preliminary internal structure bulkheads and soles-

• The rig if for a sailing vessel or motor sailor-

• The styling and features of the superstructure

• The preliminary hydrostatics

With that, I will prepare a few +)# generated drawings in order to show the proposed

layout in $lan and $rofile views and a perspective view of the proposed xterior "tyling.+ombined with a description of the proposed dimensions and other particulars of the

vessel, this is the beginning of what I refer to as "tage I or the preliminary Design

Study.

Stage I is basically a process of /discovery0 wherein we mutually discover the best

solution to your requests. In pursuit of that /discovery0 process we will review our

proposed design solutions against the original specification 11 or possibly the initialspecification will be revised according to what we discover. This process is both flexible

and adaptable.

#uring Stage I we will strive to establish the accommodations, styling, si&e, dimensions,and the target displacement. !ur goal here is to provide a 2proof of concept2 for thedesign so that further changes can be kept to a minimum. When the preliminary design

has been approved by the owner, Stage II can begin.

Stage II - The stimating Plans

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The goal of "tage II is to create the first few sheets of the actual 3uilding $lans, and to

generate a number of essential documents that will be required by builders so that an

accurate construction estimate can be provided.

The first part of Stage II involves finali&ing "tage I "tudy #rawings. The preliminary

stimating Plans will therefore include:

• The proposed "ail $lan or !utboard $rofile #rawing

• The proposed Interior $rofile and )rrangement #rawing

!nce those drawings have been approved, we can proceed knowing that further changeswill be minimi&ed. When completed, the stimating Plans Pac!age will include:

• "ail $lan 4 !utboard $rofile

• Interior $rofile and )rrangement

• "tructural $rofile and )rrangement

•

quipment 5ist• 6essel "pecification

• $ainting "pecification

• $reliminary Weight "tudy

• $reliminary $ower and %ange )nalysis

• $reliminary 7ydrostatics )nalysis

• 5ist of 3oat 3uilders "uited to the $ro(ect

• #esigners +over 5etter to 3uilders

• "ample !wners %equest for 8uotes 5etter to 3uilders

9or smaller vessels there will be three drawing sheets at this point. 9or larger vessels

there may be two or more sheets in each category. The goal of Stage II is that enoughinformation be presented in the stimating $lans $ackage that firm quotes can be

obtained from prospective builders for construction of the vessel.

If you would like to review an example of our design work up to this point, stimating$lans are available for any of the designs listed on our $lans 5ist page.

Stage III - The "uilding Plans

#uring Stage III the remaining design work is completed. With additional owner and

builder feedback, further decisions can be made with regard to equipment and finish asneeded.

The drawings, quipment 5ist and 6essel "pecification are refined and the remaining

drawings are completed in order to create a final "uilding Plans package. Thesedrawings and documents will finali&e the interior and exterior details, the machinery

arrangement, the deck plan, scantlings, construction sections, the boats final dimensions

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and hull shape, and the as1designed displacement, range, performance, hydrostatics and

stability.

The "uilding Plan Drawings will include:

•

!utboard $rofile: "ail plan or other exterior details of the hull• Interior $rofile and )rrangement: The vessels accommodations

• "ectional 6iews: "tructure and interior (oinery sections

• Inboard $rofile: "tructure and primary equipment

• #eck $lan: +abins, hatches, fittings, mooring and anchor gear

• "par and %igging $lan as needed

• 6arious "tructural #etails as needed

• "cantling 5ist

• 7ull 9itting #etails

• 7atch and #eck 9itting #etails

• +ompanionway, #oor and $ortlight #etails

• Interior oinery #etails• 'echanical 4 'achinery #etails as needed

• 5ines #rawing

• %udder #etails

!rdinarily each of the above drawing categories will include several sheets. #epending

on vessel si&e and complexity, the 3uilding $lans may include anywhere from ;< to *< or

more drawing sheets.

#uring "tage III the quipment 5ist and 6essel "pecification are finali&ed in order toaccurately describe the intent, the layout, the scantlings, the construction, the systems and

the outfit of the vessel. In addition to the above listed drawings, the followingDocuments will be included in the 3uilding $lans set:

• !ffsets Table unless the vessel will be =+ cut-.

• quipment 5ist: The complete list of equipment items.

• 6essel "pecification: #etails of the intent, rationale and construction.

• $ainting "pecification

• Welding "pecification for metal structure

• 9astening "chedule for wooden structure

• 5aminate "chedule for >%$ structure

• Weight 3udget

• 7ydrostatics and "tability %eport• $ower and %ange )nalysis

• +over 5etter to 3uilder

7aving finished "tage III, the Design Phase of the new yacht will be complete. "ufficient

information will be contained in the drawings and documents to allow any professional or

amateur builder to build the vessel as intended.


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• >ermanischer 5loyds plank1on1frame commercial wooden vessels up to ;;F

scantling length 1 applicable to larger vessels on approval-

• 3ritish 5loyds %egister plank1on1frame wooden yachts up to CE scantling length

1 applicable to larger yachts on approval-

Staility: To assess stability we use a variety of criteria depending on vessel si&e, use andlocation, as follows:

• 9or private yachts under @D meters measurement length BE feet- intended for

registry in the ?, stability will be calculated according to the ?1%+# standards

I"!1;@@;B-.

• 9or private or commercial yachts above @D meters measurement length, stability

will be calculated according to I'!, '+) or other standards appropriate to thevessel type, si&e and use.

• 9or commercial charter yachts in the ?", safety and stability will be calculated

according to the ?" +ode of 9ederal %egulations +9%-.

•

9or private or commercial yachts in the ?", stability will be calculated accordingto the new )3" @


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!rdinarily, system schematics are developed in1house by the builder e.g. plumbing, fuel

system, etc.- or by system suppliers e.g. electrical, hydraulic, air conditioning, etc.-. !n

occasion the owner or builder may request that we provide basic schematics or additionaldrawings to illustrate speciali&ed features or other details in support of construction in

order to communicate specific owner requests to the builder.

9or passenger vessels or other commercial craft there may be the requirement to provide

additional drawings and reports for documentation and compliance with the relevantstandards. )nd when a vessel is destined for use within the uropean ?nion, we can

prepare documentation that makes obtaining a + 'ark relatively easy for the builder.

*# #utting +iles

!ne of the most valuable +onstruction "upport "ervices we provide for metal boats is to

develop =+ +utting 9iles in order to automate a portion of the vessels construction.

What is =+...G It simply means =umerically +ontrolled... 3y this method a numerically

driven plasma or water1(et cutter can be used to create frames and plates for a metalvessel. !ne can also use an =+ driven router to cut mould frames for a wood or

composite superstructure. It is even possible to carve an entire male plug or female mold

out of foam for use in building a composite superstructure, directly from the computergenerated surface model that was created during the design of the boat.

This leverages the work that has already been done in order to create the design and can

provide a significant labor savings to the yard. It also dramatically improves accuracy of

construction. With =+ cutting, the labor saved during fabrication of a metal hull will

usually pay for the cost of developing the =+ cutting files, plus some.

In other words =+ cutting is an opportunity to not only effect a true cost savings by

shortening the overall build time, but to also improve the quality of the result.

The ,ole of the #omputer

Designing the "oat: We use the 'axsurf family of software products, a series of

programs for hull modeling, analysis, and construction. With 'axsurf, a preliminary hull

model is quickly generated and an initial round of hydrostatics, stability, and performance

calculations performed to see where the design can be improved. The computer generatedmodel allows the design to be enhanced quickly at an early stage of design before it has

become fixed, or even to be modified without too much fuss later in the process. In fact,without such an easily used computer modeling tool as compared to manual drafting-

those subtle refinements would rarely be undertaken even if given a substantial budget.

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"everal other benefits are also evident. 9or example, via the computer generated model it

is easy to assure that the surfaces are developable, so building a metal or plywood hull is

made simpler.

Testing the Design: With the computer generated model of the hull and superstructure

having already been created, it is a simple matter to make a scaled down physical model for towing tank testing, or to verify the styling and features of the yacht in three

dimensions.

"uilding the "oat: ) substantial benefit of having generated a model of the hull on the

computer is that the vessels structure can also be computer generated and actually pre1

cut via computer guided laser or plasma cutting 1 or in the case of a >%$ vessel, themould created using a computer guided router.

3y this method, having detailed the hull plating and structure, the parts are nested onto

available plate si&es. The completed plate nestings are then sent to the metal cutters 1

usually by email. This is extremely convenient since the cutter can receive theinformation immediately in order to start the work. When completed, the cutters have a

2boat kit2 that can be shipped wherever needed.

The Sa&ings: When building a metal boat in a production environment, assuming one1off

construction, industry feedback is generally that =+ cutting will save a professional builder some *FH or so of the hull fabrication labor. The percentage of fabrication labor

saved by an amateur owner1builder is dramatically greater. 9or example, consider that

lofting is eliminated, as are templating for frame and plate patterns. 9or an amateur builder, this also eliminates most of the 2what to do and how to do it and why2 kind of

worries... !ther 3enefits: 6ia =+ cutting an extremely accurate fit results. 9or a metal

hull this means there will be far less distortion during the weld1up.

9or construction in other materials such as >%$, =+ cutting nearly eliminates the laborrequired for lofting and for mold construction. )n entire hull and superstructure mold can

be carved by five axis =+ router directly from the computer generated model, avoiding

nearly all tooling labor. ) builder can also pre1cut glass fiber or carbon fiber cloth,

especially useful with pre1preg cloth cloth that is pre1impregnated with resin and post1cured by ?6 or by heat-. Where the materials cost is high, the improved efficiency will

quickly offset the cost of having developed the structure via computer modeling.

Design-Stream O&er&iew9or more detail on our design and build strategy please see our +)# #esign "tream

article. The following flow1charts were created in order to show our design process 1

more or less taking the usual 2design spiral2 and stretching it out into a linear diagram. Ihave used two different ways to represent the work1flow.

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• "oftware in ?se 1 This is a simplified flow chart showing the software we use,

and how a few basic software groups interrelate during the process of creating a

new yacht design.• $rocess #eliverables 1 This is a workflow chart showing our #esign $rocess

arranged in terms of the 2order of operations2 that we follow in order to create

each new yacht design. This process starts with our interaction with the client asdescribed above, then moves into the stages of the design process wherein we produce the drawings and documents that we deliver to the client, the builder, and

to the metal cutter.

#ool D odels

The following are two examples of how we make good use of a *# +)# workflow in

order to create a design and its structure, then to communicate the result using *# $#9

files for use by both client and builder.

• *# 5ines #rawing 1 This is a *# perspective file showing the lines of one of ourdesigns. )s with all of our designs, it was created in a/surf , then imported to

icrostation so that it could be 2plotted2 to a *# PD+ for customer review.

Within the $#9, you can grab the *# model, rotate it, &oom, pan, walk1through,and you can change the perspective. If you turn on the $#9 menus, you can also

manage the layers in the original +)# drawing, turning any of them on or off to

simplify the view. This is an excellent tool for visuali&ation of the spaces, and to

see the vessels shape from any angle.

• *# "tructure #rawing 1 This is a *# perspective file showing the structure of a

metal yacht design. 7aving been designed in a/surf , the vessels structure was

then created in 0or!shopJ after which the basic structure was brought into

icrostation for editing and detailing, and then 2plotted2 to a *# PD+ for the builder to use as a guide during assembly. It is an excellent way to view the

structure using simple, free (doe ,eader software. This enables the builder and

his crew to see exactly how the structure interrelates.

0hy De&elop ( *ew Design...1

)s you may have surmised from the above, there is a fair bit of work involved in

designing a boat well, even if it is a simple oneK >iven the number of designs that

already exist it may seem a little bit wild to commission a new yacht design. !n the other

hand, it is an unquestionable delight to see ones ideas turned into ones own personalyacht.

Aou will be surprised to discover that the cost to develop a new and unique yacht design

is ordinarily less than a yacht broker's typical fee to purchase an existing yacht...!

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Ill repeat that in case you missed it... ven though there is quite a lot more work involved

to create a boat design, the cost to create a new custom yacht design is ordinarily less

than a yacht broker's fee for the simple act of signing the purchase papers...!

)s a percentage of the yachts cost the amount expended on design is really not very

much. If you also consider that a custom design will be tailored to your particularrequirements rather than being an 2off1the1shelf2 solution, the difference in satisfaction

will be well worth the effort expended. This is especially so if a custom designed yachtwill better serve its intended purpose and will therefore be able to do so for a longer time,

versus a vessel built to a stock design. In other words, by not having to replace the yacht

quite so soon, the cost of custom design work will easily have paid for itself, in alllikelihood many times over.

Is It Pro&en1

The question inevitably comes up: 2 Is it a proven designG2

The answer is an unqualified 2YesK2

The basic principles of boat design, while seemingly complex, are well established. If

faithfully attended to, the success of a new vessel is assured, and the result will nearly

always be an improvement on what has been done before on existing designs. Whereunusual features or hull types are requested, it is prudent to involve tank testing, which

can provide valuable insight as to vessel behaviorJ performanceJ stabilityJ seakeepingJ

etc. What ultimately makes a boat a success is whether the vessel is safe, seaworthy, seakindly, beautiful to behold, and above all, whether the vessel satisfies the originally stated

wishes of the owner.

stalishing a Design Philosophy...

'y aim is to engender superior aesthetics along with safe and comfortable boating. )

distinguishing characteristic of our design work during the last few decades has been a

focus on =omadic Watercraft, in other words the design of truly pelagic blue water boats

for family cruising and world voyaging.

I strive for long term owner satisfaction with the resulting vessel, using the most up todate methods and design tools, including software optimi&ed for hull modeling, stability

and performance analyses. With this approach, I am able to leverage the work done to

create the design into subsequent detailing of the vessels structure in order to provide an =+ cutting file package to automate parts of the vessels construction, a process that is

outlined in our +)# #esign "tream article.

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'y goal is to provide a complete 2design service2 from the point of imagining the vessel,

to creating the ideal solution to those con(urings, in other words to take the concept all

the way from napkin sketch to building plans, and to then provide the various2construction support services2 noted above.

0here To "egin1

The place to start the design process is to first create an owners specification, or 2missionstatement.2 This can be as simple as a paragraph to describe the intended vessel, or

possibly a simple list of desired features such as preferences for rig, power, equipment,

materials of construction, overall si&e, accommodations, budget, pro(ect timing, and soforth.

The owners mission statement need not be elaborate, since the particulars will be

generated by the design process itself... While sketches or design examples are not

necessary, if preliminary sketches or examples are available, certainly they can beincluded. We refer to the owners mission statement as the 2Owner Specification.2 !nce

Ive understood its requirements I will provide our usual written Design Proposal 1

usually by return email or if necessary by letter or fax. !ur #esign $roposal is offeredfree of charge and implies no obligation. It is (ust good information for your planning

purposes... In order to pursue a design inquiry in greater detail, please feel free to contact

me for more information or to request a Design Proposal.

+reating a new yacht design is by far the most rewarding path to long term boatownership, and the process itself can be quite a lot of fun...K

What do our clients think...G $lease review some of their Testimonials to find out...

)nd for the inevitable questions about the cost of boat custom design, our DesignProposal will answer them definitively, however please also see our )rticles on the +ost of boat design, and boat building.
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