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  #91  
Old 05-03-2006, 10:33 PM
SAQuestor SAQuestor is offline
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Quote:
Originally Posted by Vega
Yes you have a point, but 35 hours in a cruising displacement boat is something like 200 miles...that's no cruising, that's a small journey. I mean a guy that builds a cruising boat, it is because he wants to cruise...at least once?
Maybe Mama gets sea sick easily? Maybe he or she got cancer and is fighting for life. Literally there are hundreds of reasons that might explain why the boat only has 35 hours on the clock. Who are we to doubt?
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  #92  
Old 05-03-2006, 10:39 PM
SAQuestor SAQuestor is offline
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Back to trollers vs Trawlers

How's this one? A 34' Bill Garden Troller or Trawler?

Shame there are no details on the link. Nice looking IMO anyway.
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  #93  
Old 05-04-2006, 05:28 AM
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Vega Vega is offline
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Quote:
Originally Posted by SAQuestor
. Who are we to doubt?
Yes, what I mean is that it is a strange situation, so caution is the word. A guy interested in that boat should also be interested in the real story that led to an unused boat.
And if it was I, I will have a boat test in that boat in some difficult sea conditions.
You know a fishing motor boat of that size has a lot bigger motor. I don't know if that engine has enough power to handle not so good weather conditions and that is supposed to be a cruising boat. It should be seaworthy.

But I agree that it is a nice hull and that the boat is not expensive.
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  #94  
Old 05-04-2006, 05:32 AM
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Vega Vega is offline
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Quote:
Originally Posted by SAQuestor
How's this one? A 34' .
That is a fine looking boat, really nice
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  #95  
Old 05-04-2006, 05:38 AM
FAST FRED FAST FRED is offline
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Location: Conn in summers , Ortona FL in winter , with big dock & room for O'nite stop .
If anyone has had the "pleasure" of hearing a Lister air cooled thumper , they easily understand why the boat is for sale with so few hours.

Anyone with a bit of competance , and a huge amount of stick to it , can build a boat.

It takes VAST experience to be able to build the air box to adaquatly cool a Lister ,
and work as a sound trap too.
Not a job for the novice , as the 2 lb per Sq ft lead Soundown matereial is really pricy ,
and multiple attempts will be required.

If a boat is willing to accept the 1.1 speed ration a doubble ender will be OK , but the ability to sprint an extra K or 2 faster (to make a bridge or lock) will be absent.

Additionally going down wind offshore the speeds may have to be reduced as the low speed stern usually adds energy to the waves and causes them to break earlier.

Does save fuel tho to operate at .9


FAST FRED
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  #96  
Old 05-04-2006, 06:15 AM
fcfc fcfc is offline
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Quote:
Originally Posted by Vega
And if it was I, I will have a boat test in that boat in some difficult sea conditions.
You know a fishing motor boat of that size has a lot bigger motor. I don't know if that engine has enough power to handle not so good weather conditions and that is supposed to be a cruising boat. It should be seaworthy.

But I agree that it is a nice hull and that the boat is not expensive.
The plea for this kind of boats is rolling. I do not think to the point to be a hazard, but certainly to the point to make the boat unliveable.

All small low speed round chine powerboats have this problem. Bigger ones also , but they use paravane or active hydraulic stabilizers (20 000$). Small boats (read low cost) are left with steady sail or bilge keel. But that have a limited action. Speed is too low to gain any dynamic stability.

Just go for a ride in beam or quartering sea in such boats. 3 ft waves are enough to quickly understand what I mean.

This probably the main reason no a volume boat manufacter builds such boats.
Fishing boats are another story. Fishermen get paid when to go to sea. Pleasure boaters have to pay to go to sea. The level of acceptance of discomfort is not the same.
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  #97  
Old 05-04-2006, 07:37 AM
Greenseas2 Greenseas2 is offline
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Stability and power

Fred, the power plant can be changed out fr the same hp Tanmar or other make engine, not a big deal. As far as rolling goes, the trollers are fairly deep footed and don't roll any more than any other hull design. We'll know more about this when I go out to Ca to research these boats more this month and ttalk with the people who use them. Also if you refer to Beebe's book on passsage making, alll of the passagemakers in the book are equipped with paravanes. I will make arrangements to take out the listed boat Fred and let you know how she is as seaworthiness goes. There are 4 other ones to take measurements from and get comments from owners.
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  #98  
Old 05-09-2006, 10:56 PM
Schoonertack Schoonertack is offline
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Tad and others, I love this thread! have tried to get it going on a number of boat forums. I wasn't going to post, but I can't resist. I have fished around where you live Tad, I have done some fishing on the Gulf coast, and wondered at the big sportfishing boats running out at speed running home at speed, very often with no flags. The thought has crossed my mind from time to time that it is passing stange to burn a thousand pounds of fuel and return fishless, How many dinosaurs to the barrel by the way? How many years to turn dino fat into high grade light crude? What is sport fishing, anyway? Flyfishing,handlining,hand trolling, site casting? Whatever, fishing is what I do most of the time when I am on a boat. I was at Fish Expo in Seattle, really enjoyed the Charterboat sessions, Lots of Six Pack guys there, at that time nobody seemed interested in fuel efficiency, two times 300 hp diesels was the norm for the bigger boats I couldn't see how they could make it I still don't. I think alot of the boats are sixties designs, I do believe that there is far more than 30 years of fuel in the ground, I don't believe for one minute that I will ever buy hightest for 35 cents a gallon again. I hope this forum has legs I think we are looking at the future of boating. All the best Guys. Schooner
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  #99  
Old 05-10-2006, 09:08 AM
Greenseas2 Greenseas2 is offline
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Agree to design vs fuel consumption

There are too many advocates of the big fuel burners.....mostly boat builder who can cram all of the amenties of a big condo in to something that floats and makes big enhancements to Exxon-mobile's bottom line. Here in southeast Florida we're starting to see the Monterey influence in economically operated charter fishing boats in the 30 to 40 foot ranges. Not fast, but do bring home the fish with some profit for the boat. Most are equipped with small head and galley with side seats for fishermen. They do seem to be doing OK.
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  #100  
Old 05-10-2006, 04:11 PM
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kjell kjell is offline
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Quote:
Originally Posted by Guillermo
Banjers (37' motorsailers) have a canoe stern and deep vee hull with full length keel, so lots of wetted surface. Full load displacement around 13 tonnes.
My boat's engine is a Perkins M 4-236 delivering a maximum of 71 HP DIN (86 HP SAE) at 2500 rpm. Continuous is 61 DIN (74 SAE) at 2250 rpm.
Propeller is a 28" x 18" three bladed one, SAR 55%, slip around 22%. Reduction gear ratio, 3:1.

At 1.06 Fn Banjers do 6.0 knots (Tested. Clean hull, calm seas, full load) at 1300 rpm of the mentioned engine, the prop absorbing something like 14 HP of the 39 HP (DIN) available from engine at that rpm (These last two data estimated, as power-rpm curves are not available).

By the way: Somebody has those curves for this engine? I'd appreciate very much if he/she makes them available to me).

Fuel consumption at this Fn is 1.08 Lts/mile (6.5 lt/h) or 0.29 gall/mile (1.72 gall/h). With a 900 lts tank, allowing for a non-usable 10%, range goes to 748 miles, if I worked out numbers correctly. At hull speed (around 7.5 kn) mileage comes down to 500 and consumption rises to around 12 lt/h
Hi Guillermo.
I have the power curve for the Perkins 4.236M how do you like me to send a copy to you?
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  #101  
Old 05-10-2006, 04:51 PM
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Guillermo Guillermo is offline
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Quote:
Originally Posted by kjell
..I have the power curve for the Perkins 4.236M how do you like me to send a copy to you?
Thanks a lot Kjell. I've got it already from the kindness of Tad Roberts, so problem has been solved already. But if your curves include the specific consumption one -because this one is not in Tad's- then I'll be most grateful if you send it to me by e-mail.
Thanks again for your kind offer.
All the best.
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  #102  
Old 05-11-2006, 06:09 AM
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Guillermo Guillermo is offline
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Kjell,
I've just received the fax with the Perkins 4236M curves. Thanks a lot again!
You're a great and most collaborative guy!
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  #103  
Old 05-11-2006, 01:35 PM
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Tad Tad is offline
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Quote:
Originally Posted by Greenseas2
As far as rolling goes, the trollers are fairly deep footed and don't roll any more than any other hull design.
Oh yes they do.

Again, (see above posts) a troller hull (the real thing) is designed to carry a load. That load is a hold full of ice and dead fish. The VCG of this load is quite high, due to freeboard, approx at the waterline or above. Loaded trollers are very comfortable in a sea, they roll a looonngg way over, but slowly. So working and living aboard for long periods is bearable. People convert trollers to pleasure boats and add ballast, usually in the form of lead in the bottom of the hold. They then complain that the boat has a snappy and uncomfortable roll.

On this coast is is usual for trollers to fit passive stabilizers called "Batwings". This is a flat steel plate extending horizontally either side of the keel amidships. The plate carries across the full beam of the boat and is braced at it's outboard end with a vertical steel plate strut, which is bolted to the hull through the topsides. Crude but effective. These are fit in addition to the paravane stabilizers which hang from the trolling poles. Pictures below.



Troller Yachts vs Trawler Yachts-lf1359_norse_provider_12.jpg

Troller Yachts vs Trawler Yachts-lw1385_ocean_challenger_05.jpg
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  #104  
Old 05-12-2006, 12:42 AM
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Guillermo Guillermo is offline
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Quote:
Originally Posted by Tad
...Again, (see above posts) a troller hull (the real thing) is designed to carry a load. That load is a hold full of ice and dead fish. The VCG of this load is quite high, due to freeboard, approx at the waterline or above. Loaded trollers are very comfortable in a sea, they roll a looonngg way over, but slowly. So working and living aboard for long periods is bearable. People convert trollers to pleasure boats and add ballast, usually in the form of lead in the bottom of the hold. They then complain that the boat has a snappy and uncomfortable roll.
I totally agree. That's why GRP for displacement fishing boats has had no success over here, except for mussel farming uses. GRP boats are lighter than wood or steel, so, for the same hull forms (And fishermen do like those forms) they need to add ballast, which makes movements at sea more uncorfortable, so they add bilge keels, or the like, etc. For mussel farming they use 18 m (typically) beamy boats, bringing mussel cargo on deck (a lot of tons!), inside the protected waters of the Galician Rías. So, stability demands are quite different and GRP has had its place for this use, competing with wood and steel. The rest of displacement boats is either wood or steel (wood the small ones and steel the big ones)

(See a typical wooden mussel boat and its structure in photos below. Also an small wooden gill-netter)

Quote:
Originally Posted by Tad
On this coast is is usual for trollers to fit passive stabilizers called "Batwings". This is a flat steel plate extending horizontally either side of the keel amidships. The plate carries across the full beam of the boat and is braced at it's outboard end with a vertical steel plate strut, which is bolted to the hull through the topsides. Crude but effective. These are fit in addition to the paravane stabilizers which hang from the trolling poles. Pictures below.
Do they carry those "Batwings" at all times? Don't they interfere with the fishing operations? (tangling nets or ropes, etc). In Galicia they go for bilge keels, as said before. I would appreciate more info and photos on that system, if you are so kind.
Cheers.
Attached Thumbnails
Troller Yachts vs Trawler Yachts-dany-1.jpg  Troller Yachts vs Trawler Yachts-heres-alaran.jpg  Troller Yachts vs Trawler Yachts-05200015.jpg  

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  #105  
Old 05-13-2006, 02:00 PM
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Tad Tad is offline
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Guillermo,

Sorry I don't have a good picture of Batwings, but I'll keep looking. They are fixed in place and totally passive, thus there forever. Lots of added drag, but fishermen being fishermen, they claim no speed reduction!! Viewed from ahead all you see are the edges of the steel plate, no stiffeners. Depending on boat size the plate might be 3/8" or 1/2" thick (10-12mm). In plan view they often taper from the keel out to the tip, so that lines will brush off. But everything gets tangled in them if you let it.

The red boat above is nice looking. Years ago we had a big sailing yacht built at the Mefasa Shipyard in Aviles, Asturias. Alejandra was launched in 1993. There was a fleet of beautiful steel fishing boats working out of that harbour, about 25m long? Maybe longliners or offshore gillnetters? Very elaborate shapes for steel.

Tad
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