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Re: how hull design effects stability
By:Nick Schade
Date: 9/2/1998, 2:17 pm
In Response To: how hull design effects stability (Stephen Bumb)

> i am just about to build a skin on frame kayak of my own design. it will
> be 12 feet long , have a 20 inch beam , and be hard chined. sort of like a
> greenland style boat. the design i cooked up has a vee bottom runing the
> entire length of the boat. I am 5' 9" 190 lbs. , i expect the kayak
> to be tippy but i will except that to gain some speed.

This sounds like it will be an extremely tender boat. V bottomed tends to have the least initial stability, then you combine this with a narrow with (20") which is on the narrow side for most people. Finally the boat is short. Stability is gained with length. You can expect this to be a scary boat.

It will not be very fast. The hull speed of a boat depends on length, and while yours might be fast for a 12 foot long boat, you will not be able to get it going very fast.

> 1. will the vee bottom hard chine design be more or less stable then a
> smooth profile design?

The chine is not going to make a huge difference but hard chined tends to be somewhat more stable than soft.

> 2. are there any inherent problems in a hard chine design? it was easy for
> me to do the lay out as a hard chine but i can smooth it out if need be.

Hard chines tend to be marginally less efficient moving through the water, but the difference is probably not too significant.

Look at John Winters site for more design info.

Messages In This Thread

how hull design effects stability
Stephen Bumb -- 9/2/1998, 12:00 pm
Re: how hull design effects stability
Nick Schade -- 9/2/1998, 2:17 pm
Re: how hull design effects stability
Stephen Bumb -- 9/2/1998, 10:11 pm
Re: how hull design effects stability
Nick Schade -- 9/3/1998, 1:03 pm
Re: how hull design effects stability
Mark Kanzler -- 9/3/1998, 11:01 am
Re: George Roberts' cute little kayak (link)
Mark Kanzler -- 9/3/1998, 11:10 am
Re: how hull design effects stability
Paul Jacobson -- 9/2/1998, 11:32 pm