How does a chine work?

[Suijin]

Originally Posted by Delancey

Far Harbor 39 designed by Bob Perry. Interesting concept for those who don't like ocean passages. Looks like a fairly short rig, which I presume is designed to lay flat on the pulpit and cabin top when it goes in a box.

http://www.containeryachts.com/container_yachts.swf

Dear lord, look at that beam. That makes it the smallest 38' boat I've ever seen and it looks really uncomfortable. The cockpit is minuscule! I understand the concept of making it fit in a container, but I can't for the life of me see why, in a boat that you're going to own, you'd be willing to make all those sacrifices for the sake of transit costs. Just pay to have someone deliver it, or put it on a boat, or just charter.

[Delancey]

Originally Posted by Cadence

This does not look like Perry's normal deigns. It appears to be for a specific purpose. Like fast. It is soft chinned but not far from hard chinned. Under water cross section can vary greatly. It is not round bellied like cruising designs.

It's designed to fit in a shipping container so that you can ship it to wherever your favorite cruising grounds are and not have to sail across oceans to get there.

[noelex 77]

Originally Posted by Suijin

Not just home-made steel boats...on the majority of professionally produced steel and aluminum boats still being made. It is dramatically less expensive to fabricate boats in metal without complicated compound shapes to the panels.

To see the metal artisans roll and wheel a flat metal sheet and make it into a compound curve is quite amazing. Of course such skills and time are not cheap.

[Delancey]

Yeah, I don't know. Kind of reminds me of a scaled down Deerfoot.

I spent some time on an old Uffa Fox boat that had a similar beam with a 64' LOA that was very narrow in the ends so probably similar volume. It wasn't so horrible. It was fast though, which is nice.

[Polux]

Originally Posted by Suijin

Dear lord, look at that beam. That makes it the smallest 38' boat I've ever seen and it looks really uncomfortable. The cockpit is minuscule! I understand the concept of making it fit in a container, but I can't for the life of me see why, in a boat that you're going to own, you'd be willing to make all those sacrifices for the sake of transit costs. Just pay to have someone deliver it, or put it on a boat, or just charter.

On that we agree and not only us since I believe very few were made (1?). Besides all that you say with that narrow beam, and even 40% of B/D ratio, considering the very modest draft (1.70m), the boat had a small overall stability and should not be fun to sail. Strange concept I mean, shipping a not very good sailing boat, when it would be cheaper to charter a better and more comfortable sailing boat on the destination.

[Delancey]

Well, here is a review from a magazine that is in the business of selling adds for what that it's worth as it relates to the topic at hand-

"Once the chine dug in and the big bulb keel started to have an effect, the boat was very stiff. Designer Perry says, "At first I wanted to give the boat a little more than a draft of 5 1/2 feet, but my client wanted the shallow draft for cruising, and the boat doesn't seem to need it-so why bother." I sailed the Far Harbour in 25 knots of wind, and I still found no reason to disagree with his assessment. The straight run of the hull and hard turn of the bilges aft helped the boat track well-even in big waves."

Far Harbour 39 Sailboat Review | Cruising World

[Polux]

Originally Posted by Delancey

Well, here is a review from a magazine that is in the business of selling adds for what that it's worth as it relates to the topic at hand-

"Once the chine dug in and the big bulb keel started to have an effect, the boat was very stiff. Designer Perry says, "At first I wanted to give the boat a little more than a draft of 5 1/2 feet, but my client wanted the shallow draft for cruising, and the boat doesn't seem to need it-so why bother." I sailed the Far Harbour in 25 knots of wind, and I still found no reason to disagree with his assessment. The straight run of the hull and hard turn of the bilges aft helped the boat track well-even in big waves."

Far Harbour 39 Sailboat Review | Cruising World

Maybe I made not myself clear. I was not saying that the boat has not enough stiffness to sail relatively well, due to the narrow hull. What I said was this: "the boat had a small overall stability and should not be fun to sail"maybe your notion of what is a fun boat to sail is different from mine: Would you say that it was for you a fun boat to sail? I do not mean funny.

Regarding overall stability it is just what I said, the boat relies basically only on the stability provided by the keel that has a relatively small draft and not an exceptional B/D ratio for such a narrow hull. As the hull provides little hull form stability, a more "normal" 38ft will have a lot more overall stability since it will join the stability from the keel to a big one coming from the hull form. To add to that, a more beamier boat will probably be more heavier (that boat is quite light) and that will increase the overall stability too.

[Delancey]

I'm not a champion for the guy or the boat. The subject of whether the designer had any experience designing chines came up, and it turns out he does. In my experience a narrow beam isn't a spoiler so just saying. As far as the Far Harbor 39 goes, well, nothin against it. Looks like two were only built so obviously the idea didn't catch on. Apparently the guy who commissioned the design loves it so I guess that's what matters. Personally, I like passages but to each his own.

[transmitterdan]

[QUOTE=Polux;1696284with the new chine concept since they are not designed to be immersed but to prevent more resistance to immersion. Those boats are not designed to be sailed over the chine, but till the chine.[/QUOTE]


How can a hull feature that never goes in the water affect the resistance to heel?

[Jim Cate]

Originally Posted by transmitterdan

How can a hull feature that never goes in the water affect the resistance to heel?

Gosh, Dan, that's a really mean question! But ya gotta wonder!!

Jim

[Polux]

Originally Posted by transmitterdan

How can a hull feature that never goes in the water affect the resistance to heel?

It seems you did not understand how a modern chine works. Modern chines mark a heel limit and are not to be immersed, if you sail with the chine in he water (over the chine) and not on the hull surface that finishes on the chine, then you are sailing badly with too much heel for the hull design, the boat is creating drag and you will go faster if you reef and go back to the heel where that sailboat sails more effectively. Sure when they are forced they will provide more stiffness but at the cost of a much bigger drag (before they are sailed over). It is a safety feature and not one that will make for more efficient sailing. Sure, it can make you go faster if you are a solo sailor or a short and not top crew. Easier sailing equals faster sailing.

If you insist on oversailig, the boat will heel suddenly till a much bigger heel angle till Max RM will stop it. That was not for accident that I was comparing the chines to learning wheels on a bicycle: They will make the ride easier but when you touch the ground with the small wheels you are going slower and by the same reason: Drag. That's why racing boats designed to be used by big an top professional crews don't have this type of chines. They are able to control the boat without them and can go slightly faster. The VOR are an exception for the reasons I had already explained.

[savoir]

How do old fashioned chines work ? I don't understand them either.

[Pelagic]

Originally Posted by savoir

How do old fashioned chines work ? I don't understand them either.

You can apply them...(or the lack of them).... in a myriad of ways.

[El Pinguino]

Up until WW2 about the only place you found hard chines on small craft was in duck punts... the high initial stability made them a very stable gun platform. Post ww2 hard chines were handy if you owned a welder and a set of plans and wanted to build a boat. Also handy if you wanted to build in plywood... nobody gave a a moment's thought to how it made you go faster..sail flatter etc... was just ease of construction.

Modern "cruising" boats.. a fashion statement... nothing more... nothing less..

The use of hard chines up frd by Laurent Giles in the Westerlys he designed such as the Centaur was a totally different matter... more usable space frd in a small boat...

[savoir]

So that guy is shooting ducks ?

Scary.