Hull Design software suggestions

[scottperkinsusa]

I have been playing with Carlsons Hull designer
which is actually fantastic even if you had
to pay for it but I was wondering if there
were any newer easy to use software programs
that are available. I dont mind paying a reasonable
amount considering I am a hobbiest and not a pro
boat builder....
Any suggestions are welcome.
Thanks
Scott

[mmd]

At www.boatdesign.net/forums there is a continuous discussion on this subject. It would be worth your while to read through the postings.

[Charles Burgess]

I have found in my experience that hull design software are a great aid in many aspects, but have yet to totally replace manual draftmanship when it comes to drawing fair lines and curves accurately. The differences can vividly be seen in comparing a table of offsets produced from a manually drawn lines set vs. that produced solely with software.

In all fairness, the software does produce accurate enough drawings for very large vessels that are built of steel and glass composites, given the fact that such materials allow for looser tolerances which the builder can accommodate.

Wooden yachts and boats are necessarily built to pretty high tolerances in regards to fitting the pieces together in a manner similar to cabinate making. If you build solely from a software/CAD drawing you are probably not going to be happy with the "fit". During the manual lofting of the drawings to full size, the builder can adjust the results to make for a tighter fit, but this comes at the cost of the additional time it takes to do so.

Additionally, there is a great deal of personal satisfaction derived from drawing some of the plans by hand, so don't cheat youself by going with only software to design your boat.

Hobbiests and professionals alike normally use both software and manual draftmanship in the design process. One must never forget that there is a great deal of art involved in the design process that requires a human touch that binary logic and mechanics are yet to duplicate.

The the above cautions in place: what software do I recommend? There are a lot of freeware that offer basic functionality, and payware that package a lot of stuff into a CAD/CAE suite that all seem to be well developed at this point in time. I recommend that you try out the demos and then make a choice, since ultimately it comes down to personal taste and how you like to do things.

Regards,

Charles

[fair&fair]

Charles,
I don't think your advice regarding 3d lofting software is really all that accurate in its own right. Just like lofting by hand, using a program takes plenty of skill and patience. When used properly, the results are just as good, and most often better than hand lofting. I think people confuse being easily able to generate an orthographically possible surface via a program with fairness, and this leads to mistakes.
The advantages of lofting/designing a hull on the computer are numerous. First off, it is much easier to generate a 3d surface on the computer then it is by hand...no doubt about it. Being able to run through a series of designs and check the hydrostatic and aesthetic differences between models takes a matter of minutes compared to hours or days. The ability to send out CAD files directly for 3d CNC cutting is a tremendous capability that hand lofting does not alow. The accuracy, symmetry and fairness of parts that are produced by this method are far beyond anything ever produced by hand lofting in wood. I know that this will undoubtedly raise some eyebrows here, but it is the truth. I have built wooden boats from files that I generated to be 2d cnc cut for frames/stations/bulkheads etc. and the result has always been nothing short of excellent. As a designer, one of the principal advantages of using a computer is the ability to send the design in an easily understood format to clients and colleagues so that modifications can be made and updated directly to the file. This saves enormous amounts of time and money.
I also take issue with your comments about wooden boatbuilding requiring more accuracy than other methods. This just does not make much sense at all. The tolerances required for any high end carbon composite construction are far beyond anything needed for a wooden boat these days (let's face it...nobody builds a competitive plank on frame racing boat these days unless class rules dictate that this is the way to do it). The fact is that we all know that wooden boats "move" as they absorb moisture, and the nature of their construction allows for plenty of shape change while the dynamic loads on the hull exert their influence upon it. The need for well-fitting joints is certainly there, but to argue that this is some how more important than say a the fit of a highly loaded ring frame on a composite boat is ludacrous.
So...I'm sorry of this comes off as a rant, because it really is not. It just seems that so often on this forum there is a knee-jerk adherence to the "old ways." Understanding the traditional methods is very important, particularly if you are lofting, and even more so if you want to use a computer lofting program. There is no question about that, and I think Charles you alluded to this fact in the above post. I guess where I differ with your opinion is in the overall usefulness of the software. I generate hand drawings for every preliminary part of a design. This happens to be the fastest and best way to do this for me, but all final drawings are done on the computer. It is far more practical and accurate than hand drawing, particularly when doing arrangement drawings in 3d.
To answer the original question...I use Multisurf by Aerohydro, and I like that quite a bit. Aerohydro has a program called Surfaceworks LT which goes for several hundred dollars, but they often run special promotions. You can get a fre 30 day trial from them if you like. The customer support is excellent. I would definitely look at the boatdesign.net forum thread that was mentioned above to get a better feel for what is out there though.

[Hans Friedel]

I use Rhino 3D and it is a nice program and not to expesive.

But compare to Hulldesigner the learning curve is much longer. As mention before you have to spend alot of time with your program if you want to use the full potential of it. There is actually a lot of craftmanship involved in surface modelling.

This kayak is modelled in Rhino and the plug is machined in a CNC mill machine. The tolerances are within a 0.5mm.

http://www.boatdesign.net/gallery/sh...cat/500/page/1

I would never go back to pen and paper

Hans Friedel

[Corso]

Rhino for me.
I use it from a long time and i didnt find it so difficult to learn, experience will permit to do in 15 minutes what at the beginning takes you a whole day, but thats the same in a lot of things, you can download the trial version and their tutorials and start from that. Your layout and understanding how surface creation works its the most important thing, anything else its way easier, if you dedicate some time to it its just a matter of a couple months to start producing some usable drawings.
For anything else its plenty of people to ask to.
As for the cost of it: there are old versions available that are perfect, if you dont use it professionally there is pratically no difference from the newer ones, prices, there, are reduced or they are for free.
Dont confuse a tool like Rhino or the other 3d ones with 2d drafting tools, for what concern the seconds doing things by hand its easier and gives you better results in less time.
BTW: knowing how to design on paper its important before starting with a CAD

[mmd]

Please, people, remember that the main difference between hand-drafting and CAD is that with CAD you can make bigger mistakes faster, and with more confidence.

There is a saying in CAD offices that goes:

Anybody can make a mistake, but to really screw up, you need a computer!

[Hwyl]

I went to a talk given by Bruce Johnson who is the cheif designer at S&S. He draws his lines on paper and then tries to match them on the computer. He gave the reason for this (paraphrasing): when he draws lines on the computer, he feels the computer has some control over the aesthetic, but when he draws by hand, he is in control. It was a really interesting talk. Other tidbits--he took his kids to show them the lofting floor in the Landing School, to find it is now being used for storage. He uses Rhino and if I remember correctly "High Seas?". He was asked how much it cost to do some very nice mock up perspectives in Rhino. He gave a numer I think it was about $8000, the same questioner asked the Lyman Morse guys how much a full size mock up would be--about $3000, but they said they'd prefer the Rhino version--one reason was that they could email mock ups to the owner and do changes instantly.

[Corso]

Im not promoting Rhino, im just one of its users (and for every designer their program is the best one, its simply a matter of habit), but thats a nice program, quite powerful for a so little package, it works with plugins and libraries so it adapts to different fields. As for boats i think that for an amateur its pretty good as it is, even because being compatable with a lot of other dedicated CADs eventual calculations would be just made exporting the drawing in one of the numerous free/shareware softwares that dont offer the same drawing flexibilty and speed.

About whats best that could be a neverending discussion, drawing a line with a pencil or with the computer its not so different and being more or less artistic (i use it for jewellery, there is not a lot of technical there) its just a matter of personal feel rather than something real, if you know how to use the program you draw with the same control on the objects that you would have with a pencil. And the bigger mistakes happens only because its faster (how many meters you can walk and how many KMs you can drive in the wrong way before noticing that its wrong?? or i should use an hand plane and a power one?), thats why its important to learn first with the pencil and paper, whatever you do you need to know how it has to be done before sitting in front of a monitor, once you know your job then the computer its just another powertool in your shop.
(as for the costs professionals feel that since they spent a lot of bucks on a whatever software, and on training, and on the guy that operates the whole, and that the computer implies (not true) precision, they should make customers pay more for it, in reality producing something on a computer cost less (per item) than handmade).

[imported_Glenn]

I use a combination of CAD and manual drafting. I first draw my lines by hand on paper making the many preliminary design assumptions for the crafts' LWL, prismatic coefficient, etc.

Next, I digitize my lines into CAD using a digitizing tablet and then with CAD I am able to easily do the job that a planimeter would do (using old school manual methods (i.e. not using a computer) to obtain my displacement at each station. I tweak my lines where necessary and voila - a well designed hull in not alot of time and not alot of expense.

[pjwalsh]

I still like to start with a freehand sketch on an 8 1/2" X 11" page which gets refined and drawn to scale still by hand - work out the midsection and two intermediate sections fore and aft. I then take the basic section dimensions off and build a 3D surface model using rhino. Not a professional user so I work out the hydrostatics the old fashioned way using rhino to measure the section areas and such - if you are reasonably accurate in the scale preliminary sketch there are not many surprises. Someday I will buy one of the hydrostatics plug ins like phaser.

I like rhino because it is pretty easy to use and you can build objects from simple entities like points and lines and curves. To me this allows more freedom of shape - and the technique is much like the way I learned to draw lines manually.

I have used autoyacht, multisurf and prolines fairly extensively also - of these I prefer either rhino or multisurf.

[imported_Conrad]

I use Vacanti Prolines 6.3 Basic, about $150. It will only do the hull, no interior cad, etc., but it's very easy to learn and use, almost intuitive, and quite powerful within its limits. I'm not a pro, have no cad experience, but do understand quite a bit about design and like to mess around. It's perfect for me.

I've heard a lot of good about Rhino both here and among friends who know cad programs. I've looked at it, but am not willing at this point to commit to learning the cad concepts/techniques/language, etc. The Prolines is very easy to learn- check out there demos here: http://www.vacantisw.com/

[Tomcat]

I don't know if they still make it, but I use Plyboats for simplish hard chine designs. I've made boats from this sofware, and the boats turn out looking good, though I was a fraction skeptical given that the boat sometimes looked a little unfair on the screen. Plyboats is like 50 bucks, and pumps out all the stuff you need, including a modeling format so you can build little models for verification.

I use Vacanti's Prolines for rounded stuff, mostly canoes and multihulls. It's a good program, and can be cheap.

I think that often people think the computer will be so easy, only because the info available on lofting and drawing boats is so dense, and largely unavailable. After 20 years in the craft, it is in many cases a lot more direct to go to a drawing than a computer drawing. It is so controlable and straight forward compared to computing. Computing preserves and develops tones more info, but if you know what you want, and are producing the output for yourself, 95% of the stuff is useless.

If you think of a great designer sitting down at a board, and considering a design, he knows what it will weigh before he puts a pen to paper. He has drawn that basic shape before, and will not be terribly surprised when he generates the numbers. Now think of a CAD slave working in a cooperative environment, sharing a design back and forth with others. There is every possibility he has never drawn anything similar before, and all the data will be very useful. The reams of junk generated will create the impresion that the design is profesional, and good value. I just don't need that kind of convincing when the idea was mine, I know what the boat will basicaly do, and I just need to generate some paterns and get started.

For multihulls where the design aesthtic is CAD, and one needs nice rounded stations, I think CAD rules. Some multi designs can be drawn faster by hand, but generaly it's faster on the screen. Multihulls are a segment where often the plans and the built boat have only a slopy connection to each other, due to the many hull building systems. In that case it is usualy more accurate to work from models.

[JEM]

I too started with Plyboats. It's a very simple and straight-forward program but I think it's a great place to start. It has it's limitations but it also gives you a great foundation to build your knowledge on.

I'm using Rhino with Autocad and a good sized spreadsheet now.

If you have experience with Autocad and can make your way around it pretty good, the step to Rhino is very intuitive.

Show us some images of your work!

[Tomcat]

I looked again at the question, and one thing it doesn't make clear is what the purpose of this play is. Logicaly the purpose would be to make designs and build boats. I suspect a far more comon reason is that an amateur wants to take a stab at yacht design.

As to the first reasoin, I've been in contact with a yacht designer who is planing on building a personal boat that will be a 50 foot podcat. He works in hard chine. Plyboats would be fine to do his design, and one could rip out the lines in a few hours. One could start building the following day, and that would soak up 2-10 years of the average builder's time right there. Any more time spent fiddling would just be wasted.

I imagine one could do the same with Prolines and B-plates, though I haven't really dug into that option as I should.

On the other hand if one wants to play yacht designer and stay as far as possible away from getting dirty, develop some personal ideas about yacht design on paper first and so forth, then really you should spend the big bucks and get a profesional program. Nothing like spending thousands of hours on a package nobody uses and developing a style and such that is based on inferior technical options. I would imagine something in the AeroHydro or Macsurf range would be cool, though I'm much out of date on such things. I would ask a few pros you respect and might even end up working with what they use. AutoCad is key also. I used ACLt for a while, but I feel like they never really suppport the small end of their spectrum. On a practical basis the smaller packages are easier to use and cheaper to keep current. Unless you really want to learn 3D drafting, all you do is export a few views of your hull DXF and develop views in 2D CAD, which even shareware can do. If you want to go the full 3D route you are wasting your time learning anything other than the main 3D packages that can ultimately get you a job, whether in this field or property development.

I enjoyed playing with this stuff, but as an adjunct to boatbuilding one of the problems is that one spends a whole slew of time developing skills, then out comes a design or two. These take 100,000 times longer to build than to design, and by the time you are ready to draw your next masterpiece you have to upgrade all your software and your computer system. I feel that even at the light end of the spectrum it's a bit of an expense, but as long as we are all having fun who cares.

[Hesp]

I very rarely draw on paper. Usually only because there isn't a computer handy, and only then for rough accomodation plans, which people like to discuss above all else. I have great faith in the ability of the computer to produce an accurate fair curve. I print out curves and look along them to check it's the curve I want. The screen just isn't accurate enough for this.

I think the biggest problem with computers isn't lack of accuracy (after 15 years I'm still amazed by its accuracy) or it's inability to produce fair lines (the lines are so fair I cry), or even its cost (how much is Rhino and how much is a set of NA drawing eqiupment?). It's biggest problem is that it's not as intuitive as a pencil.

It's a bit like learning to drive an automobile v's walking. You're all left hands and feet for a while, smashing into things and riding up over the sidewalk. Then one day you find you're only hitting things occasionally and you start to enjoy it. Most of us accomplish it in the end and wouldn't dream of walking anywhere ever again.

Learning CAD was the same. At first I spent more time concentrating on how to actually use the CAD than being creative. My designs were the equivelent of a highway pile up. But when you can draw with CAD without thinking, then it's an incredibly powerful tool, and you'll never look back.

It wasn't that long ago that paper drawings were being introduced to boat design. I don't know if these forums go back 100 years but I expect the same discusion was being had re drawing boards.

John

[Ed Burnett]

Well said John.

I too do practically no drawing by hand. Just sketches for rig arrangements etc. - nothing formal.

For me, CAD allows me to produce more accurate work in less time, and enables me to provide design information which is more useful to the builder. In the past seven years I have produced only one table of offsets. Everything else has been built from full size templates with no hand lofting.

Good CAD programs have very powerful fairing tools to allow one to asses the curvature of a line. If a designer is not able to produce a VERY fair set of lines by computer he either has the wrong tool or is not sufficiently familiar with it.

[Aramas]

You tell 'em, fellers [img]smile.gif[/img] And that from two terribly pukka chaps who have not only drawn some lovely boats, but actually had them built! <- green with envy.

Pooh-poohing CAD is a bit like turning one's nose up at power tools and waxing lyrical over the feel of a good stone adze in the hand.

My idea of a rough sketch is to whip up a 2D cartoon in AutoCAD. Pencils are for constipated mathematicians.

[Hesp]

"and enables me to provide design information which is more useful to the builder.".......Ed

Amen to that. But sometimes builders are slow to cotton on to just how useful that info is. Yes it does cost time and money to produce that info, but the time (and money) saved by the builder is out of all proportion to this. Even the home builder who isn't pricing his/her time might find they're on the water a year earlier. How do you put a price on that.

John

[Ed Burnett]

It costs about the same for me to produce full size templates as it would to generate a full table of offsets.

I tend to design ring frame based structures, and will produce a drawing of each individual frame anyway. The full size template is in essence all the frame drawings piled on top of eachother and plotted at a scale of 1:1. The templates can have each of the four corners of the frame, thus describing the bevels on the inboard and outboard faces. The frame gets set up pre-bevelled (and varnished if you like) and ready to plank over.

Also on the templates go the stem and sternpost profiles (including rabbet info) and transom true shape plus bevels. Shaft line, rudder profile, standard beam camber, you name it. Once a builder realises the potential they get pretty keen on the idea!

[Ed Burnett]

Hmmm. I wonder if adding a post to this one will make it reappear!

[JEM]

I believe the term is known as "bump".

[Ed Burnett]

More of an almighty kick than a bump I think - the thread dissappeared completely last week along with a few others.

[Tomcat]

I agree that guys who are pros will find CAD extremely useful. I'm not sure that's the question. I would find it very difficult to get by in business without email. On the other hand If I take a 15 minute break, I don't email the universe, I leave a little sticky note on the door saying "back in 15 minutes".

One runs into lots of people these days who can't do simple sums in their heads, and need a calculator for everything, they were just never taught how to do it otherwise. The same is becoming true with lines. Present company excluded, a majority of people don't seem to know how to draw lines, or know any of the quick ways to design and build things by hand that are at least as fast as using a set of full size cad drawings. Much of modern day boatbuilding has been sold as lofting free.

I wouldn't be without the computer. It's all pretty cool.

[Ed Burnett]

Tomcat makes a point which is a good one, and not something I would disagree with. For starters I really do wish I was better at mental arithmatic.

There has been a considerable amount of discussion on this topic over the years, started by questions like "Should I loft my boat using AutoCAD", and (likely from someone with little or no design experience) "What software should I use to design a small boat". It may seem at odds to my earlier posts but my answer to both those questions would be "Why not pick up a pencil and do it by hand".

The point I try to make quite frequently is that the output of the design process is a set of drawings. These can be produced in any number of ways using a variety of tools. All jobs vary, and chosing the right tool is all part of it.

In the case of hull fairing software, it is very easy to pick up a simple program and generate a shape that looks like a boat. Within a few hours anyone can "design a boat". Withing a few more seconds you can generate a whole bunch of numbers that relate to the shape. The problem I have with this is that in many cases, although the output looks like a boat, it is questionable that it is the boat that the "designer" intended. With this particular tool, if you don't know how to control it you can end up with something that is, in effect, the "default" boat for that particular software.

This plays right into the hands of all those who say things like "Computers can't draw a sheer like Hereshoff" or whatever. As far as I am concerned, if I lines plan I produce on a computer does not look as nice as it could do, that is my fault. It's not the computer that has lacked some kind of "auto-Hereshoff" feature, it's me not being able to control the tool that I am using.

I read an article in a magazine a while ago, in which a designer made a comment along the lines of "the boat ended up with a slightly pinched bow because that's what the computer wanted to do". Quite a startling admission from a professional designer. The traditional equivalent would be to say that the batten had a kink in it so that's why the boat looks a bit funny. I know the problem (my software wants to do the same thing) but I don't let it take over and will wrestle with it until I have the shape I want, not the one software tends to head towards.

Reading the posts above it is interesting to see how different people find their own balance between fully hand and fully computerised draughting. We each must pick the tools that we feel most confident with. I have nothing against a novice designer getting stuck in with a cheap hull fairing program, but when I look at the results I frequently feel they might have been better if he or she had stuck with a pencil. CAD is a hugely powerful tool, but the perception that it makes designing a boat easy leads to some pretty mediocre results.

I hope many people will continue to start at the simple end of the scale, and select tools and methods that are in proportion with the project as a whole. One of the first "designs" of mine that actually got built was a very (very) small skiff. I needed a boat in a hurry (by the end of the next day) and figured the best thing to do was nip across the road for a couple of sheets of ply and get on with it. The design process consisted of making a cardboard model, then taking it to bits and drawing around the panels. It took one evening, it was great fun, and it worked just fine.

[Andrew Craig-Bennett]

Well, it's nice to see this thread back!

I've drawn a few boats over the years, by hand, and it is amusing to pick up one of my drawings and see what mistakes I made at different ages. The only downside to doing it by hand is the desirability of having a planimeter.

I've been hugely amused to read of the woes that British warship builders apparently have with CAD. I wish I could say I was surprised, but those blighters have been cosseted so long at the taxpayer's expense that its no surprise at all. Parkinson's Law and all that.

And a comment in support of Ed:

In 1991 I was responsible for contracting what proved to be the last big bulk carrier built for a British owner in a British shipyard - CNCo's ERRADALE at Harland and Wolff, Belfast. They had a 90-strong team from Kawasaki in the yard helping them to overhaul their techniques. One comment from the Kawasaki people was, "This CAD-CAM system is far better than anything we've got in Japan!"

Compare the current state of H&W and Kawasaki...

[Hesp]

"I agree that guys who are pros will find CAD extremely useful. I'm not sure that's the question.".......Tomcat

Your absolutely right Tomcat, the question was:

" I was wondering if there were any newer easy to use software programs that are available.".......scottperkinsusa

How about Vacanti's "Prolines", from $150. These have worked well for me over the past 15 years.

John

[Bruce Taylor]

The only downside to doing it by hand is the desirability of having a planimeter.

Here you go, Andrew:

http://media5.hypernet.com/cgi-bin/U...=2&t=003068&p=