What is the effect and purpose of a hard chine over a soft, or multi chined boat?
surfing
– Last Updated: Jul-12-05 7:56 PM EST –
In bigger seas your chines can bite into the waves and make good use of them.
I find hard chines to have the needed bite to grab onto waves and use them even in open water. I think this is why I can make very good speed in steep chop with my caribou.
I would say though that wide hard-chined kayaks have a way different feel than narrow ones. Of course I prefer narrow for forward paddling.
But this is all just general nonsense for the most part. There are advantages and disadvantages to all well designed hulls and one hard-chined may not feel like the next. A good paddler will get the best out of anything.
not much
The type of chines a hull has, has little to do with the kayaks handling. Other design features of the hull are what give a kayaks It’s handling and stability characteristics. Don’t get hung up on any absolutes when it comes to chines or round hulls. Paddle a kayak and see if it has the characteristics you are looking for.
Probably the best post ever
on this site Don.
Two kayaks to test against each other
I don’t think there are many kayaks that you can directly compare soft chine vs. hard chine while keeping other variables constant, but the Seaward Ascente (soft) and Chilco (hard) might fit that purpose.
In the very uncontrolled comparison of my sharply hard-chined S&G kayak vs. my (former) soft-chined Squall, there was a noticeable major difference in turning response (with both kayaks edged while turning). The S&G turns like it is on rails, resulting in tighter and quicker turns. The Squall had a more skiddy/slidey feel. However, when sitting in one spot and spinning 360’s with sweep and reverse sweep strokes, the Squall took less effort to complete the circle.
My new kayak, a Tempest 165, seems to blend some traits of both. I heard somebody refer to it as hard-chined, but to me it looks almost soft, compared with the S&G. Regardless of what it “is,” I like it.
Don’t get hung up on hard vs. soft. Go paddle the kayaks.
ditto what Don said
hard corners are primarily a consequence of a construction technique thereafter with various hull shapes IN THEIR ENTIRETY providing a desired handling trait. Some kayaks like Neckys used the element of a hard chine in the Looksha designs primarily for distinctive marketing,then reversed the logic “hard-chines for maneuverability…” to imply the handling was a consequence some distinct edges when it was primarily the rocker.
Hard chines are a natural consequence of four panel s&g kayaks but if you paddled two common designs, a Pygmy Tern and a CLC Ch17 you’ll find the Chesapeake does not have the attributes usually associated with hard-chines,ie. maneuverability on a lean.
other than rocker,
– Last Updated: Jul-13-05 4:52 PM EST –
what other design features give good handling, Don?
Trim
differs from long to ww to surf. Affects helming and ease of steering.
sing
Good one
another comparison
a Caribou and a Merganser,for no good reason,just for fun.
This is a good question…
I have kind of been wanting to ask the same question. I can tell you what I have found, but this is not gospel, and I fully aknowledge the fact that there are many other boat characterisitics that determine the overall handling of a boat, but here it is:
I have a soft chined Dagger Meridian. Really like it. I find its soft chines to give it a smooth and steady transition from primary to secondary stability. It is very predictable and smooth when leaned. I also find that this boat (which I believe is partially due to its soft chines) tends to “slide” easily down the face of waves when in choppy water. I find it very smooth and graceful. Again, I assume this is a function of the chines, but also may be a function of the rounded bottom as well.
The very few times that I have tried hard chine boats, I have found that they have a bit less initial stability, making them easier to lean over on their side. Once they are on edge they rather abruptly hit a solid and very stable edge, making them very stable in this position for leaned turns—not necessarily better than my soft chined boat, just different. Seems like they do not have less “useable middle ground” between straight up and on edge.
I like them both.
I admit that my experience with hard chined boats is limited so I am curious to see what others say.
Matt
That’s my (limited) experience too…
Namely – hard-chined boats have a definite edge “notch” where they like to stay, while soft, rounded chines (are those even chines?) mean a smoother, continuous transition between primary and secondary. My comparison is the NDK Greenlander Pro (very hard chined, distinct notch), NDK Explorer (semi-hard, somewhat of a notch), VCP Aquanaut (rounded, no notch at all). All three are great rough-water boats.
Smooth Transition
is more likely with rounded chines. Initial and secondary stability are, however, affected more by deadrise - the angle from the keel (center) to the beginning of the chine. More deadrise (V) shape gives more secondary and less primary. Most rec boats will have little or no deadrise. Very stable. But rec boats don’t transition well to a seondary despite rounded chines because there is really very little secondary stability to speak off because of the flat bottom.
sing
More bad generalizations
– Last Updated: Jul-14-05 9:28 AM EST –
Chine shape has virtually nothing to do with stability. You can create the same degree of stability with a variety of hull shapes. See the following link for an explanation:
http://www.guillemot-kayaks.com/Design/StabilityArticle.html
While the boats you compared may have felt the way you describe, it's by no means a universal truth.
The feel of secondary stability
for someone not yet used to hard chines, the transition from stable lean to tipping is abrupt in my hard chined Tern compared to the soft chined QCC. Since we are talking about how something feels here, I should say that I subscribe to many boat designers’ claims that “secondary stability” is a myth. Nobody can acurately define what it is without referring to the “feel” which is a very subjective term.Like being pregnant, either the boat is at a stable angle relative to all the relavant factors or it is not. How the individual MOVING paddler feels the stability lessening and increasing is more a function of his sense of balance and any other pschycological factors that might be thrown into the mix. Maybe hard chines tend to feel more stable at sharp angles because they turn faster but I don’t think it is correct to attribute something like a superior fictional secondary stability to a hard chine over that of a soft chine.
It’s Not A "Myth…"
put yourself into a surf boat and edge that and you’ll find that you’ll quickly go over at a point way before you would in your sea kayak. The shape of a surf kayak – flat on the bottom and almost inverted V shape going towards the cockpit – gives this design no secondary stability at all. However, when moving fast on a wave, it does dynamic stability much like a bicyle going fast around a corner.
sing
so what?
– Last Updated: Jul-14-05 10:30 AM EST –
All you are saying is that a boat will tip at a certain point which is all that I am saying too. That is the point where it is NOT stable anymore. Before that point, it is stable. It is never almost stable, or even less stable at any given point. You feel degrees of stability because you are sentient and see (or should see) up coming changes in the variables which may affect your boat and that affects how you feel about stability.
The only time a boat suffers an actual lessening in degree of stability is when it is swamped. (I am talking about touring kayaks not surfing here so let's keep the speed under 10 knots, OK?)STABILITY IS A FUNCTION OF VOLUME, NOT HULL DESIGN OR HOW YOU FEEL AT ANY GIVEN MOMENT.
High volume boats have higher stability than low volume boats, for example. Take equally volume kayaks, one with hard chines and one with soft chines, fill the cockpit with water and see which one has "better secondary stability"
Whatever You Say, Jim… 
Funny, I was going to post
that page to make the exact opposite point. The shape of the curves are different. I thought that was the point of the page in the first place.
On the larger issue, I’m certainly in agreement that you can’t isolate just this one characteristic. Too complex a problem.
Mike
glad you agree…:-}