Single with stern thruster - no bow thruster

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Mako

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Was chatting with a guy with a single and a stern thruster, but no bow thruster. I know we've had these discussions before, and I'm a firm believer in the value of a bow thruster. However, was wondering if anyone here has a single/stern setup and can comment on it.
 
I don't have that setup but will say with a single you can usually pretty effectively kick your stern side to side. However that usually comes with a bit of forward movement that sometimes needs to be countered with reverse. Stern thruster gives you side to side minus the bump forward.
 
We put a stern thruster on our last boat. It was a trawler with twin engines but it was still very nice to have the stern thruster. I put bow and stern thrusters on our current boat. I used SideShift and they work well and are simple to install.
 
I wasn't in favor of a stern thuster on a boat, until a friend of mine pushed the stern of his boat over with his remote control, to exit onto a finger pier.

Ted
 
On or last boat we only had a helm on the flybridge. Our lab always wanted to be first up or down the ladder. When docking my wife would handle the bow line and I would do the stern. The problem was that by the time I got off the bridge to handle the line the stern had blown off the dock, so back up to the helm. With the stern thruster and a wireless remote I could just bump the stern back over to the dock, easy. Came to love having it so on our current boat i put both bow and stern thrusters. This way my wife never has to climb up on the bow.
 
Personally, on any boat I've run (single or twins) I've had far more times where a bow thruster would be useful than a stern thruster. The ability to operate it by remote is probably the biggest use of a stern thruster in my mind, as most don't seem nearly as powerful as a bow thruster and on most boats, appropriate use of engine(s) and rudder will move the stern right where you want it, but I've never run a boat where a bit of extra control over the bow wouldn't come in handy on a windy day.

On or last boat we only had a helm on the flybridge. Our lab always wanted to be first up or down the ladder. When docking my wife would handle the bow line and I would do the stern. The problem was that by the time I got off the bridge to handle the line the stern had blown off the dock, so back up to the helm. With the stern thruster and a wireless remote I could just bump the stern back over to the dock, easy. Came to love having it so on our current boat i put both bow and stern thrusters. This way my wife never has to climb up on the bow.
We also have a long walk from the helm, but usually solve that by making the first line an aft spring, then I crank the rudders over and throw one engine in forward idle before leaving the helm. The admiral normally steps off with the spring at the stern, so it's an easy step and I can slide the stern right up to the dock for her to step off. Power against that spring line holds the boat firmly against the dock while we get the rest of the lines and also lets me pull the boat back in if we've been blown off a bit while the spring line was being secured. Of course, the thruster with remote comes in handy if you're doing it solo.
 
I have a single engine full keel with stern and bow thrusters. My bow thruster is pretty weak, but the stern thruster is very effective.
Maneuvering without the thrusters is like you’d imagine for a heavy full keel single. Methodical.
The stern thruster is very intuitive for someone used to single engines. You turn the boat with the stern, like you would with the prop and rudder, except the thruster is more effective. I find it extremely useful.
 
The navy did this with a tug about 1880. USS Nina.
 

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The navy did this with a tug about 1880. USS Nina.
I saw an article where a modern trawler had a similar setup. The owner designed a hydraulic motor/prop to attach to the rear of the rudder. I don’t recall if it was solely a stern thruster, or a combo, acting as a get home as well. The prop was the size of a bow/stern thruster. Looked like a very simple and reliable system. They talked about selling the system, but I haven’t seen/heard anything since.
 
The navy did this with a tug about 1880. USS Nina.
The above design was patented by J. J. Kunstadter and retrofitted to the USS Nina. It apparently didn't work out as they reverted back to a normal rudder.

I know this as the USS Nina was an occasional dive site for my charter boat. In 1905 she became a submarine tender and supported hardhat diving operations. She foundered in a storm off Delaware near the Maryland border in 1910 with all lives lost.

For more information on the history of the USS Nina, there is a 5 page chapter with pictures (including another picture of the "revolutionary innovation of the propelling and steering apparatus", in "Shipwrecks of Delaware and Maryland" by Gary Gentile.

Ted
 
The above design was patented by J. J. Kunstadter and retrofitted to the USS Nina. It apparently didn't work out as they reverted back to a normal rudder.

I know this as the USS Nina was an occasional dive site for my charter boat. In 1905 she became a submarine tender and supported hardhat diving operations. She foundered in a storm off Delaware near the Maryland border in 1910 with all lives lost.

For more information on the history of the USS Nina, there is a 5 page chapter with pictures (including another picture of the "revolutionary innovation of the propelling and steering apparatus", in "Shipwrecks of Delaware and Maryland" by Gary Gentile.

Ted
This system looks like the rear prop is driven off the main propeller with a u-joint type system. The system I saw was independent of the main system-it was powered by a single hydraulic line (only a forward gear from my recollection).
 
Well @Lepke that tandem prop is interesting... but very weird. But hey, ya gotta hand it to the Navy that they were thinking outside the box and developed this idea barely outside the Civil War days
 
One of the research vessels I ran was a 45 foot single, right hand prop, and no thruster. It actually handled a lot like my sailboat so I never had a problem with it, I already had lots of practice. A friend had a 41 foot sailboat with a long keel and bow thruster, turning radius without the thruster must have been about 500 feet. Couldn't dock without it. It depends a lot on the shape of the hull. Some can get away without it, others not so much.
 
Was chatting with a guy with a single and a stern thruster, but no bow thruster. I know we've had these discussions before, and I'm a firm believer in the value of a bow thruster. However, was wondering if anyone here has a single/stern setup and can comment on it.
Hello,
I am almost finished with my 1983 34' Mainship II complete refit. Excluding the single Perkins w/ only 3000hrs.
Ell-Kat came with original vetus bow thruster and I installed a stern thruster.
I installed an Atlantic towers hard top and there is a fair amount of wind age.
I'm glad I have both and highly recommend both with single screw trawlers.
I have been boating my whole life, with many boats, both sail and power.

Paul Matthews
 

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Hello,
I am almost finished with my 1983 34' Mainship II complete refit. Excluding the single Perkins w/ only 3000hrs.
Ell-Kat came with original vetus bow thruster and I installed a stern thruster.
I installed an Atlantic towers hard top and there is a fair amount of wind age.
I'm glad I have both and highly recommend both with single screw trawlers.
I have been boating my whole life, with many boats, both sail and power.

Paul Matthews
How do you like the AT hardtop? I put one on a boat about 10 years ago and thought it was very well made.
 
Was chatting with a guy with a single and a stern thruster, but no bow thruster. I know we've had these discussions before, and I'm a firm believer in the value of a bow thruster. However, was wondering if anyone here has a single/stern setup and can comment on it.
 
I have a 50 foot Cherubini trawler with a single screw. It has bow and stern thrusters. By far the stern thruster is more useful than the bow thruster. Perhaps because the bow thruster is weak, but in tight places when moving forward the stern thrusted does a far better job of setting a direction.
 
I have a bow and stern thruster on my twin engined boat. They are brilliant. Yes you can do the same thing in many other ways (and they are worth practicing for when it all goes wrong) but for maximum enjoyment plus less stress fit both. Use a proportional thrust model of thruster and you come along side a dock, lock the thrusters on step on the dock, put the lines on, switch of the thrusters and the engines and have a g and t - job done
 
"By far the stern thruster is more useful than the bow thruster."

Interesting comment, I wouldn't have thought so. Thanks
 
Short answer: I have run a single screw boat with a stern thruster and no bow thruster for 4 seasons. It did increase maneuverability, but it was a compromise compared to having a bow thruster. A stern thruster is far cheaper to install because you don't need to install a tunnel in the hull.

Long answer: My family has a Mainship habit, my parents bought a 1986 34' (single perkins) that came with a stern thruster installed. I was fortunate to have use of the boat and spend quite a bit if time cruising the Chesapeake Bay on it. The family had been lifelong boaters, but this was a significant step up from a 25' walkaround. My folks upgraded to a 390 Mainship (single yanmar) with bow thruster, no stern thruster. I've run this boat quite a bit as well, a bow thruster gives you control of the bow when stopped that you just cannot get any other way. Pulling out of a slip with a cross wind, there is no way you will turn a single screw into the wind without using a spring line. If you always pull into a slip bow first, a stern thruster would be more useful in departure, but when bow out, nothing helps departing a slip like a bow thruster for a single screw boat. Now the 3rd Mainship of the family is mine, a 1980 34' (single perkins) no thrusters. I am going into my 5 year with the boat and it gets a lot of use, often singlehanded. I am in a busy marina, pretty tight fairways, pretty well protected from the wind and not current. If I were to add a thruster, I would skip the stern thruster and go straight to a bow thruster. My boat does not respond to the helm at all in reverse, but a bump of forward allows me to nudge the stern in either direction. My slip is the first (or last) of the fairway and I frequently use a spring line to depart with a southern breeze.
 
Was chatting with a guy with a single and a stern thruster, but no bow thruster. I know we've had these discussions before, and I'm a firm believer in the value of a bow thruster. However, was wondering if anyone here has a single/stern setup and can comment on it.
Had a Wilbur 34 with single screw Cat 3208 for several years and put a stern thruster on her. Best investment. I always said I can put the bow anywhere I want but controlling the stern was difficult when backing down and dealing with prop walk. Now have a Mainship 400, single screw Yanmar 370 with bow thruster. I ended up putting a stern thruster on her as well because it is a tall boat easily affected by wind. My wife and I are retired and I'm comfortable using spring lines, but she thought we should have the stern thruster too. I didn't complain.
 
Short answer: I have run a single screw boat with a stern thruster and no bow thruster for 4 seasons. It did increase maneuverability, but it was a compromise compared to having a bow thruster. A stern thruster is far cheaper to install because you don't need to install a tunnel in the hull.
My theory is that this is the explanation behind most of the boats with only a stern thruster. It's easier/cheaper to install than a bow thruster, and it's better than having none.

Let's rephrase the question: for those with both, which one would you more willingly give up? Let's assume they're both performing to spec.
 
We have a 1979 34' Mainship and are very pleased with The Sideshift stern thruster. It is a size higher than the boat called for, which seems to help move it more.
 
One of the research vessels I ran was a 45 foot single, right hand prop, and no thruster. It actually handled a lot like my sailboat so I never had a problem with it, I already had lots of practice. A friend had a 41 foot sailboat with a long keel and bow thruster, turning radius without the thruster must have been about 500 feet. Couldn't dock without it. It depends a lot on the shape of the hull. Some can get away without it, others not so much.
I have not seen a taller with a six-foot long rudder. My sailboat would park like a car with as little as 1-1.5 knots of speed.
 
Had a Wilbur 34 with single screw Cat 3208 for several years and put a stern thruster on her. Best investment. I always said I can put the bow anywhere I want but controlling the stern was difficult when backing down and dealing with prop walk. Now have a Mainship 400, single screw Yanmar 370 with bow thruster. I ended up putting a stern thruster on her as well because it is a tall boat easily affected by wind. My wife and I are retired and I'm comfortable using spring lines, but she thought we should have the stern thruster too. I didn't complain.
Hi just read you have a Yanmar 370hp is it a 8LV370 ?
I'm thinking of buying one would love your opinion
 
Hi just read you have a Yanmar 370hp is it a 8LV370 ?
I'm thinking of buying one would love your opinion
Hi just read you have a Yanmar 370hp is it a 8LV370 ?
I'm thinking of buying one would love your opinion
It's a Yanmar 6LYA-STP. I have a 2003 Mainship 400. It's been a great engine. Love Yanmar.
 
I have not seen a taller with a six-foot long rudder. My sailboat would park like a car with as little as 1-1.5 knots of speed.
But we aren’t discussing a sailboat with a large rudder. So that isn’t very relevant. Powerboats tend to have much smaller rudders. On our last twin engine boat I installed a stern thruster and loved it. It helped me keep the boat on the dock while I got down off the flybridge.
 
My theory is that this is the explanation behind most of the boats with only a stern thruster. It's easier/cheaper to install than a bow thruster, and it's better than having none.

Let's rephrase the question: for those with both, which one would you more willingly give up? Let's assume they're both performing to spec.
That’s tough to answer. I think it would vary depending on the boat. If your boat has active and predictable prop walk, the bow thruster would be more valuable. I have a friend who’s boat backs straight no matter what. He would be served very well by a stern thruster.
 
I have a single engine full keel with stern and bow thrusters. My bow thruster is pretty weak, but the stern thruster is very effective.
Maneuvering without the thrusters is like you’d imagine for a heavy full keel single. Methodical.
The stern thruster is very intuitive for someone used to single engines. You turn the boat with the stern, like you would with the prop and rudder, except the thruster is more effective. I find it extremely useful.
Most single screw tugboats have no bow thruster. But, that's no problem when you have a rudder the size of a barn door
 

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