Design and Drawing of First Boat

[dishsail]

I have read several yacht design books such as Understanding Boat Design, parts of Principle of Yacht Design, and in mist of reading Skene's Elements of Yacht Design 8th edition.

I am very interesting in getting some ideas down on paper however, I have no idea where to start. I would like to start drawing, but I don't know how to.

I will be taking some hand drafting lessons starting in Aug. However, I don't know where to start drawing or drafting boats. I have experience in Pro/E and AutoCAD.

Any suggestions would be helpful. Thanks.

Joseph

[Willallison]

There's no substitue for practice - the more you draw, the better you'll become and the easier it will be.
Very 1st thing to do, is to come up with a concept in your minds' eye - an idea of exactly what it is you are about to draw. You might for example choose to design a 30 foot cruising sailboat, or a 50 foot sports fishing powerboat. Think about what you want the boat to incorporate - how many will she sleep, how fast will she go, what sort of propulsion will you use, etc, etc etc.

Many texts suggest producing a profile 1st. The waterline is drawn, then a rough sketch of how you want the boat to look is drawn above this (underwater profiles come later).
Personally, I find it much easier to produce the layout (floorplan) 1st. Use paper with a grid on it to make it easier to keep things in proportion. For 1st sketches I use A4 paper with a 2cm grid. Depending on the size boat, each square might represent 1 or 2 metres. Once you're happy with the layout, then you can move on to the profile. The two must compliment each other - and quite often it will be necessary to go back and make changes to one drawing, because you're not happy with how it effects another.
At this point I will often lightly pencil in things like floors and bulkheads to give a better idea of how things go together.
After 10 or 20 redraws, you'll probably be happy with the end result. Now it's time to move onto a bigger piece of paper and draw your profile and arrangement to proper scale.

At this point you've only really just entered 'the design spiral' - but at least you're on your way...

[mmd]

If I may suggest one more book: "Yacht Designing & Planning" by Howard Chapelle. It is old, deals with "classic" yacht forms, doesn't deal with powerboats or modern equipment much at all, but is the best, IMHO, organized "first you do this, then you do this, then..." guidebook to the disciplined steps taken through the design process of a yacht. Many books deal with the technical details of yacht design, but few teach the organization of the process as well as this one does.

[SailDesign]

What mmd said.
I find that if you start with the "pretty pictures", then go into the shaping, etc, later you will have more idea of where to head.
Chapelle's book is a must-have, followed by Skene's.
BUT....... the best training by far is to hang out at boatyards, and look at boats, from the bottom up, to see how the various shapes "work". Without a knowledge of the shapes required, you are lost, i say, LOST!!
Sorry - ran away with myself there.

Steve

[gonzo]

I would take it a step further and say: go boating too. There is nothing like using whatever you design to bring home whatever defects may exist.

[SailDesign]

"I would take it a step further and say: go boating too"

Yup! That too. I had sort of assumed it was a given, but that can be dangerous I hear. ;-)

Steve

[Tim B]

Check out the attachment on this thread for a basic sketching method. They're only scribblings from an amateur, but they might help.

http://forums.boatdesign.net/showthr...5&pagenumber=2

Cheers,

Tim B.

[EmilSB]

dishsail,
to draft a boat is not a very hard job, but to design a good, efficient and nice boat it's a hard thing.
EmilSB

[Pointyendfwd]

Hi,

I just started drawing some lines after browsing and actually reading parts of Larsson and Eliasson. I also read parts of High Performance Sailing by Frank Bethwaite. There are numerous other books on my shelf, which go into more or less detail on related subjects, but these two should be required reading.

Another book which I enjoyed was Design your own Boat by John Teale, if I remember correctly. (Book since walked out the door in someones sticky paws.)

So this gives one a few things to think about, and then you pen a few lines which look good at the time.
I deleted old sketches off my hard drive the other day, of the twenty odd boats which I drew, maybe three remained.

I looked at some of the stuff I did and thought: " How could you ever have been so naive?"

So I suppose this proves that your "eye" develops with time, though I had the added advantage of looking at some really well-drawn boats quite a lot (Rodger Martin and Finot) and this was an influence.

I'll blah-blah again a bit later.....

You also need to understand the basic idea of fairness. If someone can tell me how, I'll post an article.

[Dim]

It is necessary for you to be registered (it not a bit too).
Further - a "post reply".
To read what types of files supports this forum.
To attach your article to your answer.
And we shall enjoy reading of new article.

This is a fantastic site I am visiting. I would like to asked whether by stretching a boat plan, in other words if the no 3 and No 4 frames are identical the boat of say lenght 14 feet is stretched by another 2 feet by including an additional farme between Nos 3&4 to make the boat longer.
My question is would it affect the performance.
Regards

[Tim B]

Yeah,

It would adjust the slenderness ratio, thus affecting the wave drag (and thus speed, higher slenderness is faster). For sketching boats, get all the information you possibly can, sail, look around boatyards, visit designers (most are happy to help) visit a towing tank (if you can) have a look at model boats, anything at all, related to yachting. In the later stages of design pay particular attention to the mast-base area and keel/centreboard (for a sailing boat) and engine, but bear them in mind at first, and it will save problems later.

Good Luck,

Tim B.

[Pointyendfwd]

Hi there Gents and Ladies,

Just a few words, if I may.

Stretching a boat will most definitely increase the speed. (One assumes the waterline gets longer and not just the overhang.)

If it is a displacement mode vessel. from 14 to 16 feet by about 0.35 knots. Which most definitely makes a big difference in a race or a long distance sail. How far are you going to travel in your now 16 foot boat, and how large a difference wil 0.35 knots make to your enjoyment?

Now, you have to remember a few other things:

1. The increase in length also increases the volume of the boat, which means it will probably float a little higher in the water, with different hydrostatics from the original (probably worse.)
2. The added station has to be faired into the rest of the hull, as two stations being the same does not necessarily mean that the line between them are straight.

Now, is all this really worth the added 0.35 knots, or should you find a larger design which suits your requirement better?

Regards,

Thank you for your suggestions.
Actualy I was not after increasing speed but the design I have is for a 14X5 feet skiff which I intended to extend to 16 feet raise the sides by six inches and then fit a small cabin and an outboard say (10 or 20Hourse Power) for an overnight fishing boat for an amateur. Width has to be less than six feet to fit in my garage next to my car.
Any website with a similar plan I can buy on line
Thank you
Best Regards