Wave Piercing Bows

[dantnz]

Not quite. The bows are already the same thickness at the deck as they are at the waterline. I can do whatever I want in terms of a profile view shape - even "s" bows! ha ha ha

It's just a foam bumper that extends beyond the real bow.

Ahhh ok. But still, anything but the most mild rake in either direction is going to look a bit odd if the natural hull development would be plumb.

Any pictures or did I miss one already in the thread?

 

[BobBill]

Bow Stems

I was thinking, foam might not be best choice for beach cat bow...balsa or pine perhaps more sturdy if stern is lifted as boat hits sand etc...

 

[brian eiland]

To me, the "wave piercing bows" are more visually pleasing than the plumb bow was when I first saw them. I think this may be because they look fast even standing still, where plumb bows just don't.
Steve

Plumb bows have almost never had an attractiveness to me....they were okay on daysailers and NACRA cats, but on larger boats just added to the boxy nature of cruising cat designs. And those straight unimaginative shear lines

The raked aft bows have their place in racing boats that wish to drive right thru the waves, but on cruising designs that don't intend to be pushed so hard into a seaway, give me a pretty overhang. And with those really narrow abbreviated fore-decks on the raked bows how are you going to get forward to fend off a piling or a dock?.....Racy looks, but limited practicality

 

[brian eiland]

Right, Teamvmg. I know. This would be a *cosmetic* change, turning this...

....into this....

It's a modification of the profile view of the boat, by extending the waterline a few inches forward from plumb and raking the line back to make the look of the new bows, as seen here in the 2nd picture.

These two are MUCH prettier vessels than either of those

 

[brian eiland]

CatBuilder, just be careful to not stick to the aesthetics only when considering the bow shape. I think there are other priorities which should be taken into account for commercial boats, like anchor handling from the bow, boarding, port fees based on length, probability and ease of damaging the protruding bow, etc. All things which racing machines don't have to worry about. If you have checked these and found them acceptable, then it's turn for the aesthetics to be put into consideration.
Cheers

Thank you

 

[brian eiland]

And who could fine fault with a bow shape like this...



...admittely it won't work on a cat ...too bad

 

[CatBuilder]

Brian, I appreciate your input, but putting those old timey bows on a sleek, performance catamaran makes me want to puke.

However, as we see in this thread, everyone has their own taste... None is better, just different.

 

[keysdisease]

Brian, I appreciate your input, but putting those old timey bows on a sleek, performance catamaran makes me want to puke.

The Spirit of St Christopher, a Peter Spronk inspired boat quietly being beautiful in the Virgin Islands. In my humble opinion this is one of the most beautiful charter catamarams anywhere, with neither plumb or wave piercing bows. And to the uninitiated eyes of her passengers, I'm sure they find her lines very pleasing.

Now on the flip side my friend Roger Hatfield has done much work with wave piercers as well as adopting plumb bows a long time ago, also a beautiful boat.

Steve

 

[brian eiland]

Bow Aesthetics

Another subject thread on bows , and my 'aesthetics' posting in particular,.... with a few more photos...
http://www.boatdesign.net/forums/sailboats/sailboat-bows-8835-6.html#post63853

 

[brian eiland]

Lock Crowther's Bulb Bows on Wahoo

Does anyone here remember the very nice redention of combination plumb/bulb bows that Lock Crowther did on his Wahoo design?

I can't access my photos right now from this remote computer, but I'll do so later. Here is a reference to them, "Loch's boats had slanted and tulip bows"

His claims that these bows both cut down some pitching as well as reduced the height of the bow wave that tended to ride up the sides of the bow, thus reducing wetness of bows.

I used these bows as an alternative on my 65 design




http://www.runningtideyachts.com/motorsailing/zoom.html



I just found one good photo that shows the bows very well
http://www.boatdesign.net/gallery/showfull.php?photo=5406

 

[BobBill]

Cat Bow Stems

I think, as I think Par implied and a few others, that the bow shapes fit the applications or the build more often than not. Some are function; some are fads.

The below original was designed to crash through and over the surf. The other is made to conquer Great Lakes chop, the Shark is (frankly) my all time fav cat, the other mono hull is plainly blue water and build (perhaps for space) work.

The aesthetics, as implied earlier, in each case is the beholder's alone, however. I like them all, really.

I also favor the idea of the removable bows to experiment. However, I have now come to the conclusion that Nice Pair's design will make for dryer sailing in most conditions, except for the circular hull shape aft of the bow, without sacrificing much VMG or hobby-horsing...but that is me, my boat and my somewhat non surf launch conditions.

 

[brian eiland]

... However, I have now come to the conclusion that Nice Pair's design will make for dryer sailing in most conditions, except for the circular hull shape aft of the bow, without sacrificing much VMG or hobby-horsing...but that is me, my boat and my somewhat non surf launch conditions.

Is Nice Pair your vessel?

What do you mean by the circular section behind the bow?

 

[hoytedow]

.....

..... Nice Pair......

Thanks for the inspiration. My boat will be named Sea Cups.

Never mind. Someone else already got it.

 

[BobBill]

Cat Bow Stems

Is Nice Pair your vessel?

What do you mean by the circular section behind the bow?

I found it hard to describe the design...it seems more flat on the bottom than appears in that pic, but the trailing hull is sort of rounded. The boat has a site on line and there is a movie clip that shows the bows underway in the choppy water...interesting.

The rounding or widening is a bit wider below the WL and then blend with the hull form, with slight rounding above.

See here... http://yachtpals.com/nicepair I think it is the first clip.

In my case, there will be a similarity, but with flat trailing hull, if that is the correct term...

I will post pic of model (working on to ascertain changes on prints before layout begins, etc.) I have not built from scratch on strong back as yet.

No, do not own the boat. Would be nice.

Based in Ann Arbor, Michigan, according to the site.

Nice Cups sounds apt...A cups, Ds or rum-filled?

 

[waynemarlow]

My understanding of raked back bows was that it had very very little to do with wave piercing but everything to to do with getting the designed maximum flotation as low as possible and keeping weight out of the ends of the boat to stop hobby horsing. The raked back bow was just an asthetic side issue that happened due to other factors.

True wave piercing shapes are very different to a raked back bow, nature certainly has designed some pretty good wave piercers and they certainly don't look like the shapes we term as wave piercers.