Full Displacement Hull

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Fish Catcher Jim

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I need a solid answer on this one cause I am not finding the web to be ofmuch help. Too many opinions and not enough hard core truth. :banghead:

Now then I am talking about a 35 foot tug with a cruising speed of about 8 knots.
On average here, what kind of water can I realisticly head out in ?
I am knew to this trawler / tug world and full displacement hulls and non plaining boats.
Planning on doing the loop/icw but I also want to do some fishing and traveling around in open water.

I know a tugs power is designed to PUSH this hull through the ocean, however with only a top speed of about 9 or 10 mph, is it practical to venture out to open water 10 to 30 miles offshore?

I am NOT going to give up some awesome fishing sooo is it even practical with a tug likie this? Not the fishing for I can fish out of AnYtHiNg !!!!!!
 
Are you thinking of Lake Michigan?

A full displacement hull is a good start to sea worthiness, then other factors come into play, chiefly windows, whether the fuel tanks are clean, and whether everything is fastened down inside the boat. It will be uncomfortable but a good full displacement should be able to make it through the 12-15 footers which are storm conditions on Lake Michigan. Whether the humans can endure is another questions. In similar conditions my arms were exhausted and sore after two hours. The autopilot wasn't able to carve the waves so I had to manually steer.

Given the distances you are talking about, 4 to 5 hours at most, weather reports are fairly accurate and you will be able to not go out or return before any real heavy weather.
 
It may help if you can give us more info on the tug you are considering. If it is a "real" tug that has been converted, be very careful. These hulls,although full displacement are simply not designed to go offshore. 12-15' seas in most small (under 80') tugs are HORRIBLE sea boats. Large engine rooms, low decks and bulwarks make for good work boats, lousy yachts.
I cringe when I see a "go anywhere" tug conversion being marketed to unsuspecting buyers.
The general public mistakenly sees a nice looking tug boat and thinks it must be very seaworthy cause' its a TUGBOAT. I have worked on many 100' tugs that have no business being in 6' seas never mind 12-15'.
The Yacht tugs aren't designed for those conditions either.
 
then other factors come into play, chiefly windows, w

Take a look at the fwd glass 3/16 or 1/4 inch or 1/2 inch. BIG DIFFERENCE!!

This will give an answer to what was in the mind of the folks that put the boat together.

Most folks look at the weather , so a non blue water boat does often venture out , however they seldom can make passages .

The chance of being caught out in an afternoon is no big deal, the chance on a 10 day passage gets higher.

Contemplate what one wave breaking in the cockpit would do.
 
I need a solid answer on this one cause I am not finding the web to be ofmuch help. Too many opinions and not enough hard core truth. :banghead:

Now then I am talking about a 35 foot tug with a cruising speed of about 8 knots.
On average here, what kind of water can I realisticly head out in ?
I am knew to this trawler / tug world and full displacement hulls and non plaining boats.
Planning on doing the loop/icw but I also want to do some fishing and traveling around in open water.

I know a tugs power is designed to PUSH this hull through the ocean, however with only a top speed of about 9 or 10 mph, is it practical to venture out to open water 10 to 30 miles offshore?

I am NOT going to give up some awesome fishing sooo is it even practical with a tug likie this? Not the fishing for I can fish out of AnYtHiNg !!!!!!

Your speed estimates are in line.
Assuming that all 35 feet of tug equal the waterline length:
Hull speed = 1.34 X squareroot of the waterline length
= 1.34 x squareroot of 35
= 1.34 x 5.92
Hull speed = 7.9 knots or 9.1 mph.
How many HP you got?
 
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Nordic Tug or other "pleasureboat" type would be ok for occasional fishing forays in decent weather. A converted work tug, no. I wouldnt take it out of the bay/harbor in nice weather. That hull is DESIGNED to be tied to something else. And just my opinion, they are the worst available hull type for a pleasure boat. Very inneficient, if repowered sensibly and ballasted correctly the snap roll will break your neck, low gunnells invite water aboard, etc. But they do look cool.
 
The OP is asking is it safe to go offshore 10-30 miles, to fish presumably in a full displacement, 35' trawler. He is not asking about blue water passages.

Yes, it is absolutely safe. Forget about the windows discussion. It will probably take 8-10' seas to push green water over your bow and hit the windows full on with more than just spray. You aren't going out in those conditions and they aren't going to sneak up on you if you check the weather first before going out.

I know that you are considering downeaster hulls. These can handle those conditions better because of their long deep keel, but not because of any better windows. And these are not full displacement hull types.

The Lord Nelson 37 you mentioned will handle fishing offshore just fine.

And you will never find hard core truth on the internet. Just a bunch of opinions that you have to sort through and come to your own conclusion. So now you have mine.

David
 
Just to be clear..... Below is a 36' tug, the Dorothy Mackenzie, she is 15' wide, draws about 7' of water, has 700 HP installed turning 40" props in Kort nozzels. This doesn't seem like the greatest cruising boat, so I'll assume you are asking about a motoryacht and not a tug?

DorothyMack.jpg
 
I need a solid answer on this one cause I am not finding the web to be ofmuch help. Too many opinions and not enough hard core truth. :banghead:

Now then I am talking about a 35 foot tug with a cruising speed of about 8 knots.
On average here, what kind of water can I realisticly head out in ?
I am knew to this trawler / tug world and full displacement hulls and non plaining boats.
Planning on doing the loop/icw but I also want to do some fishing and traveling around in open water.

I know a tugs power is designed to PUSH this hull through the ocean, however with only a top speed of about 9 or 10 mph, is it practical to venture out to open water 10 to 30 miles offshore?

I am NOT going to give up some awesome fishing sooo is it even practical with a tug likie this? Not the fishing for I can fish out of AnYtHiNg !!!!!!

There is no such thing as hard core truth and if you really require it, boating probably isn't right for you. One person will take a 12' sailboat where another wouldn't go with a 100' Expedition vessel.

For your question there is no way to give you a good answer without knowing more about the boat. Tug encompasses a lot of boats from some quality production boats to commercial boats to steel hulls someone has just thrown a cabin on. Is there a specific type boat you are talking about?
 
Need a few more details to give any solid advice. There are a wide range of tugs out there. Is it a work tug you are considering?
Check the history. What was it designed and used for. This will give you a clue to what type of water it will handle.
Be careful though. If it is being sold because its drivetrain is nearing the end of its working life, it could be a costly rebuild.
 
Hull type is the kicker here. A converted commercial tug with a flat aft section and recessed props, low gunnells, and all the other things that make it a good push boat are the opposite of what is needed for cruising. I've been asked many times while cruising the ICW to go to idle speed for an approaching tug so as not to swamp there engine room when they have the doors open. Of course, out in the big blue they are buttoned up tight. And there are ocean going tugs and inland tugs, big difference.
 
Here's a sketch of an old-style 36' tug, I think I made this about 20 years ago. Called Fearless, she was designed for traditional plank-on-frame construction and power was to be a 6-71.

This is a full displacement hull.

Fearless.jpg
 
The idea of seaworthyness is to stay on top of the water so an extremely heavy vessel that one could say is half sunk seems to be at a disadvantage.

On the other hand a feather light vessel that is easily overturned and/or easily suffers physical damage from wave action also seems to be at a disadvantage.

A trawler would seem a better pick for the OP than a tug since the tug is only a style game played on the consumer. The Ranger Tugs are light planing hulls and there's not much that sticks out w the AT or NT that sets it above the rest as a seaworthy boat. Perhaps the OP should forget the silly tug stuff and look at seaworthy trawlers.

Having said that I will admit my favorite boat is a 32 NT. But in a blow in Clarence Strait I'd rather be aboard my 30' Willard.
 
Yikes

:facepalm:
First off I want to thank you for all the replies and I guess I just took for granted that the type of vessle I was talking about would have been on every ones thinking. :facepalm:

Ok rosborough and lord nelson and sundowner tugs are some of the ones I have been looking at and learning more about them. Hp ranges from 150 to 400 and both single and twins and all diesel powered. 35 foot range give or take a little.

The great lakes yes and the icw and open water both north and south atlantic and some day the pnw.

Looking at both trawlers and tugs and a marine trader double cabin and an albin north sea cutter and like David said many DE hulls as well. I am NOT asking any one to make up my mind. See i joined the forums to talk with those who have experience with certain types of boats so as to learn and get true facts and not fiction for I am no longer simply just thinking about myself and or some good ol fishen buddies. Have family now and safty and some comfort play a big role and ...........Fishing!!!!!

I am also concerned with keeping my air draft to no more then 15 feet so as to have less of a head ache on the icw. (bridges) I also am looking for easy access to for and aft and by that I mean walk way with some depth so as to not see some one go overboard trying to scurry to the bow or deck trying to tie up and keep boat off lock wall. For me its all easy and good but again its not just about me anymore.

Too Funny here, guilty of the ocean yaught thing.....looked at a 40 foot super sport and I admit it looked inviting with all the comfi cozy liven and soooo much fishing features but i believe it was twin big block gas and that justdoes not sound like a good combination for cruising the icw and longer runs on open water.....Ohhh but sure was confi cozy looking.

Thanks again for all your time and replies....keep them coming please !
Jim
 
Oh and this too

Plan on spending much time living on the boat. No the boat wont be to small for us nor will anyone go stir crazy however i dont want a chair on the deck to be my only option for sitting besides a dinette. No I dont need a 50 foot ocean sedan. :rofl:

My main concern is safty and not being limited to rivers and bays etc. Twins vs single and being able to handle some wind and waves if need be.
Thanks again
Jim
 
Here's a sketch of an old-style 36' tug, I think I made this about 20 years ago. Called Fearless, she was designed for traditional plank-on-frame construction and power was to be a 6-71.

This is a full displacement hull.

View attachment 33229


She has beautiful lines Tad.
 
Here's a sketch of an old-style 36' tug, I think I made this about 20 years ago. Called Fearless, she was designed for traditional plank-on-frame construction and power was to be a 6-71.

This is a full displacement hull.

@Tad, 20 years agoo... 1994 you still designed in wood.....
 
>Hp ranges from 150 to 400 and both single and twins and all diesel powered. 35 foot range give or take a little.<

A 36 ft dissplacement boat needs perhaps 60 hp MAXIMUM at the prop if its full bodied. L / B 3-1 or so.

Many do well with 30 or less hp. 2 GPH.

So a 75 HP HD engine would be fine , or a 120hp farm implement or light truck marinization would be fine too.

>..looked at a 40 foot super sport and I admit it looked inviting with all the comfi cozy liven and soooo much fishing features but i believe it was twin big block gas and that justdoes not sound like a good combination for cruising the icw and longer runs on open water.....Ohhh but sure was confi cozy looking.<

Most white boats do not operate 200 hours a year , although up and down the ICW at 6K would double that , as would the loop. But these are not every year trips.

Over a period of years the gas engines , basically just above idle , would be cheaper in terms of fuel, maint , repairs with low use.

Sure they get crazy thirsty if you open the throttles , but self control, is possible.

Find what makes you most comfortable , not a cookie decision, because the words tug or trawler sounds sea worthy.Most are lakes and bays boats with the ability to stick their nose out in fair weather Only.
 
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I'm trying to get back to the original question here. It is a little confusing to me what you are asking. It seems that Displacement Hull, Tug, and Fishing are operative terms but I don't understand if you are asking permission or wondering if it is possible to have 2 out of three items from the menu. And then later safety is mentioned. And possibly a voyage from the Great Lakes to the PNW via the Panama Canal? My short answer is NO! But if I were to contemplate a voyage from the Great Lakes to the PNW fishing along the way, with a family aboard, at 7 knots, gasoline propulsion on a budget, this is how I would do it. Get a nice 35ft. RV with a V-10 gasoline engine and a 17ft Boston Whaler Montauk with a 75HP 4 stroke Honda. Leave Michigan when the lake freezes over and head to the Florida Keys and fish yourself silly. Then about April 15th work your way around west Florida fishing and drinking as you go. When you hit Alabama set a direct course for Seattle WA and don't stop till you see the Olympic Range! And make sure that Whaler has a CQR -45 as the main anchor!
 
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Minimum 450 feet of 3/8 ht chain if using the CQR. Now a good spade, maybe 50 foot of 3/8 nylon, YMMV. But seriously a motorhome and a good fishing boat is hard to beat.
 
The idea of seaworthyness is to stay on top of the water so an extremely heavy vessel that one could say is half sunk seems to be at a disadvantage.



I cannot disagree strong enough. Of course I am talking fishing vessels not tugs though. For any big weather I would much rather be on my uncles 58', which draws over 10' and has less then 2' of freeboard midship, then almost anything else <100'. Probably is closer to 1' of freeboard when tanked for crab. I have been is 35' seas and it handled them as well as anything else I have been in.

The hull design has so much more to do with sea worthiness then the freeboard and draft.
 
Ok rosborough and lord nelson and sundowner tugs are some of the ones I have been looking at and learning more about them. Hp ranges from 150 to 400 and both single and twins and all diesel powered. 35 foot range give or take a little.

I'm not jerking your chain Fishy, just trying to keep a check on reality. Sometimes marketing hype gets out of hand. Rosborough (the 246) builds planing boats, not tugs. The Lord Nelson Victory Tug (37') designed by James Backus, is in his words "Lines based on the traditional New England Lobsterboat"!!! If this is true it's the most bizarre juxtaposition of jargon ever....But she is also not a tug. And the Sundowner designed by Jack Sarin is a semi-displacement hull, not a tug at all.

None of these boats are intended for use 30 miles offshore, though on a good day they will be just fine out there. But 30 miles is 4+ hours at 8 knots, which is too long.

For fishing 30 miles out and general cruising I would recommend something like a Wilbur 34 or 38, or if you like more yachty, a Sabre or an Eastbay.

1983 Wilbur Flybridge Sedan Power Boat For Sale - www.yachtworld.com
 
The OP is asking is it safe to go offshore 10-30 miles, to fish presumably in a full displacement, 35' trawler. He is not asking about blue water passages.

Yes, it is absolutely safe. Forget about the windows discussion. It will probably take 8-10' seas to push green water over your bow and hit the windows full on with more than just spray. You aren't going out in those conditions and they aren't going to sneak up on you if you check the weather first before going out.

I know that you are considering downeaster hulls. These can handle those conditions better because of their long deep keel, but not because of any better windows. And these are not full displacement hull types.

The Lord Nelson 37 you mentioned will handle fishing offshore just fine.

And you will never find hard core truth on the internet. Just a bunch of opinions that you have to sort through and come to your own conclusion. So now you have mine.

David

Thank you David!!!
 
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For fishing 30 miles out and general cruising I would recommend something like a Wilbur 34 or 38, or if you like more yachty, a Sabre or an Eastbay


Now we're talking! Good Maine boats the first three. Except for a Sabre (unless it's painted white, Moonstruck). Perhaps also a Duffy, Wesmac, Stanley or Kass?
 
A walk of the docks in Milwaukee and a few discussions with the fisherman guys there will get you many of your answers. For sure, good boat heat is a must.
 
I used to know what a tug hull was (river, coastal, ocean going) and I used to
know what a trawler hull (eastern seaboard, north sea) was. But with all the yacht marketing BS I no longer no what this means without a clear description (photos preferred) of the hull.
 
This forum and its title is a primary source of confusion as to what defines a recreational "trawler." The site's subject concerns cruiser motor vessels (typically semi-planing hulls with two over-powered engines and sporting a flying bridge), not just sub-displacement-speed, full-living-accommodation motor vessels.
 
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I used to know what a tug hull was (river, coastal, ocean going) and I used to
know what a trawler hull (eastern seaboard, north sea) was. But with all the yacht marketing BS I no longer no what this means without a clear description (photos preferred) of the hull.

Take it easy, Poke. Even full displacement hulls can be so varied in their sea-worthiness that while one might roll you like crazy and the other snap your neck. Mine is a full displacement and bounces like a cork, working your legs to death.
 
Tad- You hit the old heart strings with the tug design, It would fit in glass construction within the Pilgrim, Lord Nelson, American Tug, and Nordic Tug field. Surely you had construction cost estimates at the time. Would that they could be extrapolated to current cost say on a 12 boats constructed basis for discussion. Really a timeless design.
Maybe due to my age and having been around tugs of this appearance growing up it is a architectural history lesson and fond memories that make me dewy eyed.

There is a similar authentic tug that appears much as your design called the "Sandman" in the Puget Sound area. It is an "Open House" operating display.

Tugboat Sandman

On the "Dorothy Mackenzie". This is a West coast B.C. Canada fleet tug, right? There is another tug outfit B.C tug outfit that runs Pink, White and Black colors. Here in South East Alaska, where this company occasional operate, they have acquired the nick name "Pink Panther" (with affection) What is amazing is the horse power these little rigs have and the pulling power they demonstrate. These rigs come by pulling tandem and the barges are not small or lightly loaded either.
How a crew (assume two) operate and reside on the lengthy hauls they run makes one believe time off is a dream come true. Just attempting to visualize the crew accommodations is a mind twister.
Love seeing them come by the house along with viewing photos of them.

Al:flowers:
 

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