help finding research material kayak design

[BATAAN]

Also Pygmy Boats of Port Townsend WA has a nice catalog with design info as well as their well thought-out easy-to-build kits for all types of kayak.

[Petros]

I think you are way over thinking what you want to accomplish. I am an engineer and have built 13 small boats, 9 of them sea kayaks. I have never gone to the detail you are looking for in any of my designs (even though I can if I wanted). The data you seek does not exist because there is no commercial value in it. I know many of the kayak designers in this area and most could not design anything larger than a row boat. They do not have the knowledge because they do not need it for a kayak design.

Traditional boats like kayaks were never really "designed" but evolved over many trial and error constructions. Since the person in a kayak makes a very large difference in the behavior of the kayak, you can not look at a kayak objectively, it is up to the individual's skill and desires, as well as size and weight. A person the same weight but taller than another will make the kayak behave very differently.

You must first try out a number of different designs for yourself, and than try to quantize how the hulls are different so you can some objectives measures to compare them to your paddling experience. Just the number alone will tell you nothing useful.

You can make a low drag hull, but if it is uncontrollable it is not a very practical kayak. You must have some experience with being in various kayaks to know what you are looking for in the design.

With that said I would not bother with scaled kayaks, I would build inexpensive skin-on-frame kayaks using sheet plastic and packing tape or inexpensive cloth and paint as the skin. You can build them in 20 hours or less (I have done in as little as 14 starting from lumber, that includes the ripping down of the stringers and cutting out all the parts). You can than build them quick and try them out, the skin on frame is also easy to alter quickly.

If you really wan to quantize the variations, that would be the way to build a data base that is specific to you and how you use it.

You might also read this website, email Matt Broze, he has a very long list of different kayak charactristics that he measured himself. Him and his brother have taken a break from making kayaks, but their site with lots of good info on it is still active. There are also free programs for analyzing kayak hulls.

http://www.marinerkayaks.com/

Good luck.

[ancient kayaker]

Originally Posted by BATAAN

Read "The Bark and Skin Boats of North America" by Adney and Chapelle, "The Canoe, A Living Tradition" by John Jennings and possibly "Building the Greenland Kayak" by Christopher Cunningham.
All have extensive notes on design factors and will answer your questions.

Yes indeed! The Inuit and other northern people in Greenland and Russia and other northern countries have had hundreds, even thousands of years to perfect their concepts. despite being limited in many cases by material shortages. A traditional kayak is created by dimensions based on body size and boat purpose, rather than tape measurements and analysis. This has resulted in designs that were highly refined long before European man arrived to admire and document them.

The numbers that hydrostatic and hydrodynamic analysis will provide will enable you to compare one boat with another. They will be of limited help in optimizing a boat for you individually and for whatever application you have in general.

I am not saying that it is impossible to design a kayak to fulfil a given purpose using modern design methods and computed values. I am saying that, unless the numbers themselves have some significance to you, it is a waste of effort. Even to a professional boat designer, the numbers for a kayak mean little unless that designer has the experience to interpret them.

If you want to build a boat that is a first time success, you will need a workable design. If on the other hand you wish to experiment and are prepared to design and build several, learning as you go, then stay in touch, describe your experiences, we will be glad to help.

That was my own approach. I built at least 3 more or less useless canoes, which are a little faster and cheaper to build than kayaks, before I achieved a useful boat. A lot will depend on material availability in your area.

Learning boat design is probably a bit like medicine, all the study and theory in the world is worth little without the internship that provides the practical experience. I recommend, if you do not already have it, that you download a copy of FreeShip and be patient enough to master this useful boat design aid. It will provide basic hydrostatic and hydrodynamic information on a hull design. Be aware that hydrodynamic analysis is based on approximations and guesswork to a large degree, on simpler applications such as FreeShip.

[gwkennedy]

I've been designing and building small paddled (or rowed) boats off and on for more than 50 years. Some of them were good, some were very good, a very few were poor. Most of these were based on the simple fact that boats are pointed on the end and float. As I gained experience, knowledge, and ability I improved my designs. Up until I started designing what I call marathon (preferably ultra-marathon) boats I thought I was doing pretty good. I'm a natural long distance paddler, so that's what I like to do and most of my designs tend to reflect that inclination. My first attempts at marathon race boats told me that I had ignored a lot of subtleties of design hydrodynamics. Those little subtleties made a lot of difference--for that task. I'ts been many years of research, more experience, and more prototypes but I believe I've improved and learned a lot in that time. The biggest thing I've learned and can tell you is that small paddled boats are task specific. You must decide what you want to do with the boat and design for that task. Certainly there is a little overlap in designs, but the dictating factor in the design should be the primary task. There is no perfect general purpose small boat design. We can come pretty close to perfect for single tasks though. The design of recreational boats makes little difference as long as they serve the purpose and they look good. In fact--I'll go as far to say that most small boats (designs) are sold on looks only. It's only when you exceed the potential of any particular design that you realize you might need another boat...

[terhohalme]

Originally Posted by breschau

Mr. Cthippo
Mr. Terhohalme
I am asking what scaling factor will be suitable not advocating a certain number.

1/1 is best.