Boat Building Forum

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Re: Strip: Short and narrow design
By:Nick Schade - Guillemot Kayaks
Date: 10/14/2011, 10:03 am
In Response To: Strip: Short and narrow design (Robert Shapiro)

There is a very simple reason short boats tend to be wider. Boats float due to displacement. If you weight 100 kilograms you need to displace 100 kg of water. 100 kg of water is a specific volume of water. It is 100 liters of freshwater or 0.1 cubic meters or 100,000 cm^3. So if you have a hypothetical rectangular kayak that is 3 meters long and 45 cm wide it will sink 7.4 cm into the water to float that 100 kg.

If you make the length less the same volume will be displaced only if the width or depth is increased. Typically designers do it with both. So if you now have a 2 m boat and keep the width the same the boat will draw 11.1 cm, or you could increase the beam to 60 cm and have a draft of 8.3 cm.

This is simple physics and there is no way around it. While having a deeper draft is a solution to keep the boat narrow, this has consequences in the design. For example the boat needs to be taller to have the same freeboard. Sinking deeper in the water can also make the boat harder to turn

Messages In This Thread

Strip: Short and narrow design
Robert Shapiro -- 10/13/2011, 3:40 pm
Re: Strip: Short and narrow design
Glen Smith -- 10/13/2011, 4:18 pm
Re: Strip: Short and narrow design
Robert Shapiro -- 10/13/2011, 4:42 pm
Re: Strip: Short and narrow design
Glen Smith -- 10/13/2011, 5:21 pm
Re: Strip: Short and narrow design
Bill Hamm -- 10/13/2011, 7:00 pm
Re: Strip: Short and narrow design
Jeff Horton -- 10/14/2011, 8:22 am
Re: Strip: Short and narrow design
Bill Hamm -- 10/14/2011, 8:33 am
Re: Strip: Short and narrow design
Allan -- 10/14/2011, 5:08 pm
Re: Strip: Short and narrow design *PIC*
Jeff Horton -- 10/14/2011, 5:44 pm
Re: Strip: Short and narrow design
Brian Scarborough -- 10/14/2011, 7:30 pm
Re: Strip: Short and narrow design
Brian Scarborough -- 10/14/2011, 7:33 pm
Re: Strip: Short and narrow design
Bill Hamm -- 10/14/2011, 7:53 pm
Re: Strip: Short and narrow design
Allan -- 10/14/2011, 8:11 pm
Re: Strip: Short and narrow design
Stephen Troy -- 10/13/2011, 4:54 pm
Re: Strip: Short and narrow design
Robert Shapiro -- 10/13/2011, 5:26 pm
Re: Strip: Short and narrow design
Etienne Muller -- 10/13/2011, 6:42 pm
Re: Strip: Short and narrow design
ancient kayaker -- 10/13/2011, 7:18 pm
Re: Strip: Short and narrow design
Etienne Muller -- 10/14/2011, 8:51 am
Re: Strip: Short and narrow design
Charles Robinson -- 10/13/2011, 7:43 pm
Re: Strip: Short and narrow design
Nick Schade - Guillemot Kayaks -- 10/14/2011, 10:03 am
Re: Strip: Short and narrow design *PIC*
Yostwerks -- 10/14/2011, 10:36 am
Re: Strip: Short and narrow design
Yostwerks -- 10/14/2011, 11:36 am
Re: Strip: Short and narrow design
Charlie -- 10/14/2011, 11:42 am
Re: Strip: Short and narrow design
Yostwerks -- 10/14/2011, 11:53 am
Re: Strip: Short and narrow design
David Bynoe -- 10/14/2011, 3:52 pm
Re: Strip: Short and narrow design
Etienne Muller -- 10/15/2011, 10:20 am
Re: Strip: Short and narrow design
Mike Savage -- 10/15/2011, 2:34 pm