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Re: performance "stitch and glue"
By:Paul G. Jacobson
Date: 8/3/2001, 4:02 am
In Response To: performance "stitch and glue" (Wolfgang)

Best performance?

It all depends on what kind of performance you want: Sailing, surfing, whitewater, straightline speed, slalom type turning, etc.

Remember that Stitch and glue is a PROCESS for connecting plywood panels,
while wood strip construction is a 3 dimensional modelling technique that gives you a boat. Although the strips are usually edge glued, they COULD be connected by stitch and glue.

The fastest rowed boats are the long racing shells, which have such rounded hulls. If you are looking for a smooth, round hull, there is a lot to be said for using plywood, and probably joining the pieces with stitching and gluing.

On the other hand, if you are going to use a computer to develop some theoretical "best" hull design then you will probably build it using thin wood strips, as they can be bent to follow very complicated design lines. Hopefully, what the computer says is a good hull will actually perform well once it is built.

In real life , though, a good design assembled by the stitch and glue process should give performance that will be so close to that of a stripper that the difference will be very hard to measure.

So, what you are really going to be comparing is the difference in designs, not the construction methods. In this case there seem to be two camps -- and they are divided on the concept of whether the cross section of the hull should be round or boxy. If the boat is boxy then it has a "hard" chine, which enthusiasts claim contributes to straight tracking, and sharp turns. The water acts on the flat surfaced sides of the boat much like water would act on a rudder.

On the other hand, round bottom enthusiasts go for reduced wetted area in the attempt to get maximum hull speed, and also look at a hull shape that increases stability as the hull is tipped. By tipping the boat they get fast, sharp turns.

What you end up with is two different ways of using the advantages of the different hull shapes for turning and for speed. The argument over which is "Best" is still raging.

To make matters more complicated, there are some boat designs that use several narrow panels to forn the hull shape. These end up as multiple chine or "multichine" designs which supposedly combine the best attributes from both round bottom and hard chine designs. These are built using stitch and glue.

So, you have asked a difficult and provocative answer and I hope I could clarify the matter even if I could not directly answer the question.

PGJ

Messages In This Thread

performance "stitch and glue"
Wolfgang -- 8/3/2001, 3:01 am
Re: performance "stitch and glue"
LeeG -- 8/3/2001, 3:46 pm
Re: I meant to say *NM*
LeeG -- 8/3/2001, 4:43 pm
Re: I meant to say
LeeG -- 8/3/2001, 11:07 pm
Re: performance "stitch and glue"
Nick Schade - Guillemot Kayaks -- 8/3/2001, 8:59 am
Re: performance "stitch and glue"
Paul G. Jacobson -- 8/3/2001, 4:02 am
Re: performance/stability hull shape
Randy Knauff -- 8/3/2001, 4:57 am
Re: performance/stability hull shape
Paul G. Jacobson -- 8/3/2001, 3:50 pm
forgot my "or" : )
Randy Knauff -- 8/4/2001, 1:14 pm
Re: forgot my "or" : )
Paul G. Jacobson -- 8/5/2001, 7:56 pm
Re: performance "stitch and glue"
Wolfgang -- 8/3/2001, 4:57 am