Coolboats to admire

bmiller

Super Anarchist
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Buena Vista, Colorado

Ex Harry Tabard
Think the cabin might fit me well.

View attachment 554767

View attachment 554768
I have the Chuck Paine book on his designs, that boat is in it. Great story behind the design. The dodger and davit greatly change the look of the boat. There was a wind vane steering originally also.
 

Kris Cringle

Super Anarchist
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A designers words:
70F44440-777F-4D5E-BADD-7F9DBFA292C4.png
 

accnick

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That's an interesting boat, actually, whatever it is. Flush deck, high bulwarks, a snugged-down cutter rig. From the looks of it, a cruising boat that is actually racing. Seems to be at least 10 people in the cockpit, which is a lot of people in the ass-end of a boat going upwind in a seaway like that.

The boat might feel a little better in those conditions with half the crew off watch and down down below on the weather side. With those bulwarks, there's no real way to put them on the weather rail comfortably. Besides, that would be a bit cruel under the circumstances. At least get them stacked on the weather side of the cockpit.

Having said that, I've spent more than my fair share of time on the weather rail of a racing yacht going uphill offshore in similar conditions. Not a heck of a lot of fun, but that's sailboat racing.
 

Steam Flyer

Sophisticated Yet Humble
45,362
10,182
Eastern NC
Craziness. Why design a boat for the 1% of it's working life spent doing that? Aside from the fact that (as observed by others) the people in this photo are doing it all wrong.

Looking at this photo, it seems to me that it is an exceptional circumstance such as a harbor entrance or river bar, rather than open water sailing just bashing along. If this boat were truly sailing in all-round conditions suggested by this photo, they'd be making negative VMG as the wave crest and the windage of the hull up the air would hurl them backwards several boat legnths, after which the boat would need to re-attached flow in the water and try to regain som of the distance lost before encountering the next wave crest.

I'm sure it makes the sailors feel all tough and manly, like REAL sailors arrrrrgh! Maybe that's the whole point.
 

SemiSalt

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Tad had a follow-on post with more explanation. Here is the text. Copying the pis is more than I can handle before breakfast.

Seastream 43, yesterday I posted a photo of a Seastream 43 pitching over a short and steep sea. The photo raised some comments so I did a bit further study of the boat, and made a quick and dirty model of the hull to show it's form. The boat was designed by Ian Anderson in 1981 and approximately 35 of them have been built. I would characterize this hull as short (on the waterline), fat, and heavy. Looking at the lines drawing today we notice very pinched ends with all the hull volume bunched up midships. Beam is 14'0”. This shape was influenced by successful racing boats of the day, all built to be fast and to rate low under the IOR rule. The pinched ends were an effort to make the rule think the hull was smaller than it was actually, and smaller hulls were considered slower, thus a lower rating. It turned out that translating IOR shapes into cruising boats didn't really work that well once they were overloaded with a full hardwood interior, big engine and bigger tanks, teak decks, and on and on....

The Seastream's design displacement is 32,000 lbs with about 11,000 in ballast, all the photos I've seen show the boats floating significantly deeper and all are down by the bow. Pitching is amplified by weights in the ends of the boat, Newton's first law tells us that motion is conserved, once something (say the anchor and chain, or a dozen people in the cockpit) gets moving, it is not easily stopped. If there's little or no volume in the ends of the hull, there's nothing to slow and damp out the pitching.
 

accnick

Super Anarchist
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Tad had a follow-on post with more explanation. Here is the text. Copying the pis is more than I can handle before breakfast.

Seastream 43, yesterday I posted a photo of a Seastream 43 pitching over a short and steep sea. The photo raised some comments so I did a bit further study of the boat, and made a quick and dirty model of the hull to show it's form. The boat was designed by Ian Anderson in 1981 and approximately 35 of them have been built. I would characterize this hull as short (on the waterline), fat, and heavy. Looking at the lines drawing today we notice very pinched ends with all the hull volume bunched up midships. Beam is 14'0”. This shape was influenced by successful racing boats of the day, all built to be fast and to rate low under the IOR rule. The pinched ends were an effort to make the rule think the hull was smaller than it was actually, and smaller hulls were considered slower, thus a lower rating. It turned out that translating IOR shapes into cruising boats didn't really work that well once they were overloaded with a full hardwood interior, big engine and bigger tanks, teak decks, and on and on....

The Seastream's design displacement is 32,000 lbs with about 11,000 in ballast, all the photos I've seen show the boats floating significantly deeper and all are down by the bow. Pitching is amplified by weights in the ends of the boat, Newton's first law tells us that motion is conserved, once something (say the anchor and chain, or a dozen people in the cockpit) gets moving, it is not easily stopped. If there's little or no volume in the ends of the hull, there's nothing to slow and damp out the pitching.
I see nothing particularly IOR-related in that hull shape. It is a fat, heavy cruising boat, with a nominal "fast cruiser" underwater profile from the early 1980's, with a passing relationship to dual-purpose boats from that period. No boat with a huge amount of weight in the ends goes well in the conditions in that photo.
 

SemiSalt

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I think Tad's opinion could be summarized as it would have been better if the same pile of material had been used to build a boat 10 feet longer
 

accnick

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slug zitski

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SemiSalt

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Even the big boys get airborn and hobby horse

View attachment 555957

True. Some of the film of the original America's Cup J class boats shows deep pitching when encountering wakes in low wind conditions.

I have faint memories of talk about anti-hobby horsing geometry some time in the past. I never saw a detailed explanation, but I think the idea was to be sure the natural resonate frequency of the bow was different than that of the stern so the two parts of the fore & aft rotation didn't reinforce.
 

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