Our CAD Yacht Design Process

Our CAD Yacht Design Process How We Use CAD to Design Boats And to Develop CNC Cutting Files For Pre-Cut Boat Parts

Copyright 2011 - 2015 Michael Kasten Copyright 2011 Updated December 2015 This page contains a summary of ho ! use CAD during the de"elopment of a ne yacht design# and then le"  building the "essel by direct use of the computer-generated model% &s &s an e'tension of this article# please also  prefer (U)*+  prefer (U)*+ +urface Modeling to Modeling to originate our boat and yacht design% The Design of a ne yacht is ordinarily di"ided into three basic stages, !% The reliminary Design +$etches !!% The +tudy . /stimating lans !!!% The inal *uilding lans% Those are the basic Design tages  that must be completed before a ne yacht design is ready for the builder% Design Process itself please re"ie my separate article on Custom Design% Design% *elo ! ill focus instead on the of good use# and ho the C&D generated D model can be le"eraged for actual construction of the boat% *eyond the "arious essential design  tas$s re3uired hen creating a ne "essel# there are se"eral actual !oat designer can become in"ol"ed% or e'ample# a natural e'tension of the designers or$ is to detail the "essels order to ma$e pre-cut boat parts% *elo# ell ha"e a loo$ at ho the design and the building processes are augmented by the "arious softar  Marine Design# !nc% 4hile e ma$e e'tensi"e use o f basic "icroso#t O##ice softare such as $%cel for nume specifications and Ado!e Acro!at  for generating plots and final documentation# the folloing article ill ins speciali6ed softare tools - generally referred to as 7CAD7 8Computer &ided Design9% :ur 7CAD Design trea& 7 is best understood if it is separated into  #our discreet design related boat buildin designer# plus to additional tas$s done by the cutting shop an d the builder%%% per the folloing outline, 1% Creating the Design 2% ;enerating the +tructure % Detailing the arts <% (esting the arts 5% Cutting the arts =% *uilding the *oat These "arious tas$s are outlined belo# separated according to ho each tas$ ma$es use of "arious different

'( Creating the Design M:D/>!(; 4e begin the design process by modeling the general shape of the hull# dec$s and superstructure% or the initi found Ma'surf  boat and ship design softare to be intuiti"e# highly capable# and accurate% &t the beginning of any boat design pro?ect e ill create a model ithin Ma'surf Modeler # using a collectio :ften this is done by modifying an e'isting Ma'surf design to suit a ne re3uirement% 4hen it is arranted# model - usually borroing elements from prior designs in so doing% The "a%sur#  model is refined as needed for the emerging concept design% 4hen the model has been sufficien the 7container7 for s$etching in the preliminary accommodations layout% 4ith feedbac$ from the preliminary l model ill be re"ised to suit% The "a%sur#  model is refined as the design matures# so that at the end of the design process the model can be draing% The completed model ill include the hull# bul$heads# soles# tan$ faces# dec$s# bu lar$s# houses# su and other appendages% !n other ords# the model is as complete as it can be in terms of the structures that defi internal compartments% &(&>@+!+ !n addition to its e'cellent modeling and fairing tools# "a%sur#  also has a "ariety of tools for assessing preli  programmable calculation sheet hich can be set up to pro"ide nearly any hull-form related calculation 8e%g% fuel re3uirements# etc%9% or further analyses e ma$e use of "arious other components of the "a%sur#  softare family such as Ma's stability and trim# Ma'surf )esistance 8Aullspeed9 for resistance# Ma'surf B 8+&(9 for sailing performan 8+ea$eeper9 for sea $eeping . motion analysis% :ur primary stability and trim analysis tool is H)dro&a%# herein e are able to model the tan$s and analy6 additionally has comprehensi"e built-in tools for assessing compliance ith "arious international stability crit !+:# the !M:# and the U+ Coast ;uard% To understand the rationale behind hy e consider (U)*+ +urface Modeling to be a superior approach not "essel but also for the sa$e of accurate analysis# please see our (U)*+ +urface Modeling eb page% D)&4!(; :nce e ha"e finali6ed the design e ill begin to detail the model for construction% +ince e use other C& and detail draings# e ill e'port the lines as 2D or D D ireframe "ies for further detailing ithin a 4e find that C&D offers a number of efficiencies that may not be readily apparent% or e'ample# by comparis  pencils and erasers on "ellum# ithin a C&D based or$flo e are able to 3uic$ly migrate myriad details fr 

efficiency not readily accomplished ith hand drafted details% &lso e are able to ma$e changes more 3uic$ly urther# the C&D draings can easily be shared across our local n etor$ or by email# alloing us to co-de"el design team members locations% :f e3ual "alue is that 7screen shot7 images or D plots of the emerging des as a communication tool ith our clients - also independently of our respecti"e locations% 4ith C&D# hen the design is completed# e can offer the same $ind of support to the boat builders in the fo cases# directly "ia the C&D files themsel"es%

''( *enerating the tructure !f the design is to be (C cut# the "a%sur# -generated D (U)*+ surface model ill be ope ned directly ithi the construction &odule  of the Ma'surf suite of programs% &s can be seen in the images to the right# ithin Wor+shop  e are able to automate the generation of the "es structure# including placement of stringers and frames% :nce the frames and stringers are defined# 4or$shop frames so that they precisely match the hull shape# and ill calculate and place the "arious cutouts for the stri lates are also defined ithin 4or$shop# and the plate shapes are then e'panded onto flat sheets% 4hen completed# the entire collection of 4or$shop parts are e'ported as 2D D entities 8the e'panded plate for further detailing and nesting ithin a separate C&D system%

 rames /'ported from Wor+shop  to ,hino - Clic$ for >arger !mage

'''( Detailing the Parts D/T&!>!(; 4e use "icrostation  for C&D drafting# for (C parts detailing# and for (C plate nesting% NC ?ust means 7 general term e use to refer to the process of cutting out metal boat parts from flat sheets using a computer dr  ays that the cuts are accomplished on steel are to use an o'y-fuel flame or a plasma ?et% or cutting aluminu abrasi"e ater ?et or a router% !f the design ill be (C cut# the parts ill first be generated ithin the Wor+shop  program# then e'ported in and detailing ithin "icrostation % Microstation can or$ directly ith D and D4; files from an) "ersion of AutoCAD% This is a tric$ that rather intentionally ill not9 do% "icrostation  is also able to import '*$ files and )hino .(/d& files if desi further (U)*+ surface modeling or detailing% &s can be seen in the images to the right# ithin Microstation the 4or$shop-generated parts are being edited necessary# additional parts are generated% *y con"ention# hether e are or$ing in 2D or in D# ithin Micr  frames imported from 4or$shop upon the body "ie imported from Ma'surf in order to "erify that the "ariou

correctly interpreted% 4e ill also superimpose any prior interior or other rele"ant "ies by attaching C&D re :nce detailed# the parts are labeled and grid lines are edited or added as needed% Te't# mar$ing lines# cut lines  placed on separate layers# each of hich are color coded according to the re3uirements of the (C cutting ser" nested# large parts ill be cut into smaller pieces for the sa$e of efficient nesting onto standard plate si6es% P0O11'N*

&t this stage e create 7lot iles7 of the assembled parts that illustrate their layout and assembly% or e'ampl entities 8prior to nesting9 and the plates are arranged to sho their relationship to each other and to the hole% These 7lot iles7 are turned into a series of PDF files hich are then sent "ia email to the oner and the buil  be needed% The oner# builder# and the builders subcontractors or "endors can plot the D draings to scale copy shop plotting ser"ice% &dditionally# the actual parts assembly files are occasionally useful to the builder# in hich case they ill be p directly to the builder - also by email%

'2( Nesting the Parts &t this point# the 7lot iles7 of the parts assemblies are preser"ed as-is for future reference% Those files are th here they are further detailed for (C Cutting% Creating the actual Cut iles consists of performing the slicin a"ailable plate si6es# then organi6ing the C&D files and the entities they contain per the re3uirements of the c The files are first organi6ed so that each file only c ontains parts ha"ing the same plate thic+ness % There ill o rames# lating# Tan$ aces and >ids# /ngine +tringers# +tem and Keelson# and for +tringers 8if there is suffic arrant de"eloping longitudinal stringers9% Then the 7stoc$7 plate si6es a"ailable from suppliers are dran into each file to scale# an d the frames or other efficient nesting% or e'ample# all parts of .7 thic$ness ill be ithin one file so that# using standard .7 sh gi"en sheet can dra upon any .7 part for ma'imum nest density% !n order to get the most efficient use of plate# e ill ordinarily do most of the nesting manually% +oftare is not smart enough to ma$e the "arious decisions re3uired to achie"e an efficient nest of parts# for e'ample to that it can be most easily elded bac$ together after cutting% 4hen the nestings are complete# there ill be an array of stoc$ si6ed plates of e3ual thic$ness ithin each file of parts% &dditional labeling is introduced to identify plate si6es# plate thic$ness# alloy specification# etc% rior cut lines are error chec$ed ithin "icrostation  in order to correct any minute line crossings# unintended smal duplicate entities% inally# the nested parts are output as D or D4; files for use by the cutters 8ho almost uni"ersally use & D . D4; files are the actual completed 7Cut Files %7

2( Cutting the Parts Cut Files3 +ince it is far less e'pensi"e to send the parts definitions by email than it is to send the cut metal b ill alays try to ma$e use of metal cutting shop s that are closest to here the boat ill be built% 4e ill asse into a series of 4'P archi"es# and ready them to be sent by email directly to the cutter ho has been chosen fo

The builder ill ordinarily purchase the plate and ha"e it deli"ered to the cutters or in many cases the metal s in-house% &fter the parts ha"e been cut they ill be shipped to the builders yard% !n this ay# the builder ordin materials# as ell as the cost of cutting and shipping% 1a!!ed Parts3 &mong the images shon to the right# one illustrates an (C cut plate that has been deli"ered t for the sa$e of easier shipping% *y this means# although all of the parts ha"e been pre-cut# small tabs ha"e be the part edges% This is done so that the parts all remain in easily handled# easily shipped# and easily referenced matter to cut the small tabs to release the parts% !t also allos the builder to instantly tell if any of the (C-cut are common in (e Eealand and &ustralia# but oddly this is not often done in (orth &merica% "ar+ings3 !n the tabbed cut plate image to the right# ta$e note that the parts ha"e been mar$ed ith an in+-5e to use the plasma or ater-?et heads for etching the mar$ings% This is brilliant# as it "astly speeds up the mar$i and te't are accurate and easy to read# and the in$-?et does not impose any heat or stress on the plates% &gain# common don under but# oddly# not in (orth &merica% 6ualit) Assurance3 During the cutting process# our follo-through is an important part of our design ser"ice% essential in order to accommodate the "arying re3uirements of the "arious different (C cutters e encounter%  built in (e Eealand# e ill customi6e the ?ob to their specifications and adapt the nestings to metric plate s

+ince e or$ ith a "ariety of metal cutters# it is often our practice to first send one component through the often this is the rudder# since it is relati"ely small but consists of precise foil shapes for the lifts# and a precise component is satisfactory to the builder# has clean cut edges# and the parts accurately fit together# then the rest sent through% :n the other hand# if a builder has established a reliable trac$ record ith their cutter of choice# this precaution%

2'( Building the Boat 4hy is !uilding  the "essel listed as one of our design stream stages%%%F *ecause by the time the metal arri"es at the builders yard# we will have already done quite a bit of the actual our computers...! +o although e do not build boats per se# e are indeed "ery much in"ol"ed in the actual boatbuilding proce nested# sent out and (C cut# e maintain a close relationship ith the b uilder as ell in order to be sure they fabrication should be accomplished%

Other "aterials((7 Though the abo"e summary has focused on metal boats# (C cutting can also be used for router cutting of ply structures# hether they are for hull and dec$ structures# or for boat interiors% /"en on a metal boat# the interio other flats can be detailed accurately ithin the C&D model# then pre-cut and deli"ered to the builder% @et another application for the D modeling methods described abo"e is for direct D cutting% Aere# the (U)  directly by a 5-a'is router to car"e out the shape that has been modeled% Most commonly this ould be used t for ;) construction of a hull or superstructure% This approach sa"es an enormous amount of the builders inshop space% ¬her application of this technology is to create a scale model# hether ?ust for fun# or to "erify the aestheti tan$ testing% or a bit more information on this please see our brief eb article on rototyping G De"elopmen & somehat unusual pro?ect is the prototype shon abo"e and to the right%%% !t is the iranha# a prototype . co in "a%sur#  and rendered in ,hino% The intent as to ha"e a mould cut by (C router so that the "arious body or the iranha# Ke"lar and "inyl ester resin ould yield a structure thats stiff# light# strong%%% and bullet proo or the iranha retro-rod e could elect to ha"e the (C router car"e a female &ould and e ould be able to immediately% Aoe"er the (C cut moulds are typically made of reinforced foam# so they are only good for up !f a larger production run ere anticipated# e ould instead ha"e the (C router car"e a male plug for each p much more durable mould for each part% This ould permit ma$ing many do6ens of ;) body parts from the This $ind of (C Cutting technology is ell established for all manner of manufacturing endea"ors# and there $cono&)((8

A Design-trea& Overview The folloing flo-charts ere created in order to sho our design process - more or less ta$ing the usual 7d into a linear diagram% ! ha"e used to different ays to represent the or$-flo# plus a lin$ to our Ma'surf pa the softare described abo"e%% •

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+oftare in Use - This is a simplified flo chart shoing the softare e use# and ho a fe basic so the process of creating a ne yacht design% rocess G Deli"erables - This is a or$flo chart shoing our Design rocess arranged in terms of th follo in order to create each ne yacht design% This process starts ith our interaction ith the client the design process# and finally produces the draings and documents that e deli"er to the client# the Ma'surf  - +oftare for *oat and @acht Design%

Cool /D "odels The folloing are to e'amples of ho e ma$e good use of a D C&D or$flo in order to create a design communicate the result using D D files for use b y both client and builder% •

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D >ines Draing - This is a D perspecti"e file shoing the lines of one of our designs% &s ith all o "a%sur# # then imported to "icrostation  so that it could be 7plotted7 to a D PDF for customer re"ie the D model# rotate it# 6oom# pan# al$-through# and you can change the perspecti"e% !f you turn on t manage the layers in the original C&D draing# turning any of them on or off to simplify the "ie% Th "isuali6ation of the spaces# and to see the "essels shape from any angle% D +tructure Draing - This is a D perspecti"e file shoing the structure  of a metal yacht design% A "a%sur# # the "essels structure as then created in Wor+shop  after hich the basic structure as bro editing and detailing# and then 7plotted7 to a D PDF for the builder to use as a guide during assembly the structure using simple# free Ado!e ,eader softare% This enables the builder and his cre to see e interrelates%

Design 'n#or&ation 4hile e regularly de"elop (C cutting files as d escribed abo"e# we do not sell "parts kits"  per se% !n other  materials% !nstead# e offer Building Plans  and NC Cutting Files  for any of our pre-e'isting designs# or for services  for design# analysis# and parts de"elopment% :nce e ha"e completed a ne custom design# or hene"er e ha"e pro"ided a client ith one of our pre-e' ma$e recommendations and introductions to 3ualified builders ho e consider to be suited to the tas$ at han ill prefer to pro"ide a bare hull# others a poer-aay pac$age# and yet others ill only ta$e on the constructi <hough our *uilding lans pac$ages are "ery complete# e "ery much prefer to stay in"ol"ed during the bo might be clarifications desired on the part of the builder# or if there are possible changes introduced by the o  draings might be re3uested# etc%

Where 1o Fro& Here(((7 or pricing and ordering information on any of our pre-e'isting boat designs and (C cutting files# please see 4hether e create the (C files from scratch# or o ffer them as part of a stoc$ design pac$age# e still include metal cutting% !n ad"ance of de"eloping any ne boat design or other modeling pro?ect and prior to de"eloping (C Cut ile Design Proposal  that includes an estimate for our or$ that is based on the scope of the pro?ect that has been or more information about creating (C Cut files for any of our designs# or possibly to generate (C cutting fi contact me as needed%