Retro fitting stern thrusters

gravygraham

gravygraham

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I've just had five minuites peering into my copy of MBM and their stern thruster article. Would anyone who's had one retro fitted care to share their experience with the forum?

The sweaty palms and exchanging addresses in the marina are beginning to get me down. My most recent one was a Dutch gentleman. At least he had the decorum to address me as 'Capitain', and not 'oi, you fekkin idiot'. I think the forum needs a hall of shame.
 
gravygraham said:
I've just had five minuites peering into my copy of MBM and their stern thruster article. Would anyone who's had one retro fitted care to share their experience with the forum?

The sweaty palms and exchanging addresses in the marina are beginning to get me down. My most recent one was a Dutch gentleman. At least he had the decorum to address me as 'Capitain', and not 'oi, you fekkin idiot'. I think the forum needs a hall of shame.
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with a twin engine shaft drive they really are unnecessary. And my company fits them. Get a days training it's cheaper. And can be transformational. But I do do training too (not over there though) So I have 2 axes to grind, and I'm suggesting the cheaper one.

I've just refitted my boat and could easily have added a stern thruster when I did the bow thruster, even if the benefit was marginal. I didn't bother.

exception = twin engined nordhavns (yes the big ones can be twins)

Single shaft boats really benefit though, the bigger the engine, ie the bigger the prop walk, the more this is true.
 
Personally I would fit one - I have had a stern thruster fitted on the last 2 boats and would always have one in the future. As marinas get tighter and tighter, the ability to stop the boat, look over the side (get the remote) and move sideways into the berth makes life a million times easier. Essex fitted the stern thruster and of course it is easier than a bow thruster as it is just a hole and no tube along with power (which is probably closer from the engine room to the stern than engine room to bow) and the control cable.

Picture when unit was mounted.

DSC00058%20-YBW.jpg


Andrew
 
admillington said:
Personally I would fit one - I have had a stern thruster fitted on the last 2 boats and would always have one in the future. As marinas get tighter and tighter, the ability to stop the boat, look over the side (get the remote) and move sideways into the berth makes life a million times easier. Essex fitted the stern thruster and of course it is easier than a bow thruster as it is just a hole and no tube along with power (which is probably closer from the engine room to the stern than engine room to bow) and the control cable.

Picture when unit was mounted.

DSC00058%20-YBW.jpg


Andrew
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Each to their own, but you can move a twin shaft boat sideways as long as you have a bowthruster, you don't need both bow and stern. But you like having both, and there's nothing wrong with that.

It's not much easier to fit, we charge the same generally for bow or stern thrusters.

The tunnel is expensive, you need to make a hole, stick the tunnel on (it is underwater, it has to be perfect), fabricate a support for the motor as it's horizontal and the tube can't take the torque, and fabricate a dry well around the motor (which of course is inside the boat) in case there is ever any bilge water. And the access, generally, is awful.
 
My boat was fitted with a sternthruster when I bought it and I find I seldom use it for 2 reasons. First you can achieve nearly the same effect with twin engines and second its not nearly as powerful as the bowthruster and the reason for that is that the bow of any boat offers much less resistance to being moved than the stern. So if I try to move my boat sideways using thrusters only, then the bow moves much faster than the stern and the boat doesn't actually move sideways at all but it pivots. Having said that, if you think that fitting a sternthruster will give you more confidence, then by all means fit one but make sure its as powerful a model as you can bolt on to your transom and equally important, make sure it is as low in the water as it will go because a thruster of any sort just a few inches below the water surface is as useful as a chocolate teapot
 
Elessar said:
with a twin engine shaft drive they really are unnecessary. And my company fits them. Get a days training it's cheaper. And can be transformational. But I do do training too (not over there though) So I have 2 axes to grind, and I'm suggesting the cheaper one.

I've just refitted my boat and could easily have added a stern thruster when I did the bow thruster, even if the benefit was marginal. I didn't bother.

exception = twin engined nordhavns (yes the big ones can be twins)

Single shaft boats really benefit though, the bigger the engine, ie the bigger the prop walk, the more this is true.
Click to expand...

Moving a twin shaft boat sideways with a bow thruster and asymetric prop thrust is easier to control and more precise than stern and bow thrusters (see Deleted User's post). Agree with Elessar, one or two half day training sessions concentrated exclusively on mooring techniques in different weather conditions will really help and cost a lot less than stern thruster installation. A good pal of mine got only a 1/2 day training just this spring after six seasons on the water and it transformed his confidence as well as his ability. Nothing to be ashamed about - if pilots weren't trained and regularly retrained I don't think many of us would fly.

The benefits of using ropes, springs and fenders combined with boats controls when entering or exiting a berth are not to be under rated. Most of us blokes like to 'control' everything with controls and switches and tend to ignore rope work. I've found the 'ball and spring' a great 'get out of jail free' card on windy days when the thrusters can be overwhelmed. After training as you gradually build confidence through experience mooring will become one of the nice bits about boating.
 
oceanfroggie said:
Moving a twin shaft boat sideways with a bow thruster and asymetric prop thrust is easier to control and more precise than stern and bow thrusters (see Deleted User's post).
Click to expand...
Just one caveat to my comment. On my boat at least, the props seem to have a big 'bite' on the water in that if I engage the gears, even momentarily, to move the stern sideways, the boat moves a lot. The stern thruster is more useful for making fine adjustments to the position of the stern. However, overall, I would say that there is nothing you can do with a stern thruster that you can't do with the engines and therefore IMHO, a stern thruster falls into the category of nice-to-have rather than essential.
Agree entirely with your comments regarding the use of lines to spring boats on and off pontoons and IMHO this is something everybody should learn about even if they don't use it often because one day for sure the thrusters will not be working when you think you need them:)
 
admillington said:
I have had a stern thruster fitted on the last 2 boats and would always have one in the future. As marinas get tighter and tighter, the ability to stop the boat, look over the side (get the remote) and move sideways into the berth makes life a million times easier.
Click to expand...
Blimey, I can't help but smiling at this sentence.
If I would know for sure that thrusters could make my life 1.1 times easier, I'd fit three of them. :D
 
Elessar said:
Single shaft boats really benefit though, the bigger the engine, ie the bigger the prop walk, the more this is true.
Click to expand...

I've had this thought myself with my MF 925, going backwards with the propwash really means going in circles to port. I have to either set up an appropriate angle first and then end up where I need to be or steer like a loon with the bow thruster and look like an amateur.

Option two is my usual option.:)
 
I had a fairline 36 with no bow or stern thrusters , twin shaft and I got in anut of everywhere using two gearboxes and brute force.

Bought current boat s/h with both a bow and a stern thruster. I prefer to moor where possible using engines alone with minimal thruster use but in strong winds or tide they make a huge difference.

We fit thrusters and a stern thruster depends on how the boat is built in the transom area.

I assume you are twin shaft ? hole for thruster plus four bolt holes, motor needs to be above the bilge so it does not get wet and yet the thruster as low as possible in the water.

Side power are the muts nuts also get the exetnsion cowls on either end of the tube to stop air from above the waterline being sucked in and to direct the thrust lower down they make a difference.
 
I have a single engine shaft drive, with bow and stern thrusters fitted as standard. Despite mocking of my gadgets by some of the neighbouring boat owners, and at pontoons when visiting, I wouldn't be without them. I guess the mocking must be envy!
 
Bandit said:
I had a fairline 36 with no bow or stern thrusters , twin shaft and I got in anut of everywhere using two gearboxes and brute force.

Bought current boat s/h with both a bow and a stern thruster. I prefer to moor where possible using engines alone with minimal thruster use but in strong winds or tide they make a huge difference.
Click to expand...

As a matter of daft male pride I try as much as possible not to use the bow thruster when mooring with twin shafts, and feel slightly sheepish if on rare occasions I have to press the dasterdly thruster switch, but it's there to be used when needed so to heck with pride our gel coat is more important. :)
 
ricky_s said:
I've had this thought myself with my MF 925, going backwards with the propwash really means going in circles to port. I have to either set up an appropriate angle first and then end up where I need to be or steer like a loon with the bow thruster and look like an amateur.

Option two is my usual option.:)
Click to expand...

On an MF 925 stick your helm amidships and use your bowthruster as a rudder when going astern. Works perfectly. Bowthruster manly too. Nothing amateurish about that.
 
oceanfroggie said:
The benefits of using ropes, springs and fenders combined with boats controls when entering or exiting a berth are not to be under rated. Most of us blokes like to 'control' everything with controls and switches and tend to ignore rope work. I've found the 'ball and spring' a great 'get out of jail free' card on windy days when the thrusters can be overwhelmed. After training as you gradually build confidence through experience mooring will become one of the nice bits about boating.
Click to expand...
:cool: agree completely. Although we rarely visit UK style marinas, the yotties I constantly compete with in harbours seem to be able to tie their boats and everything around themselves with metres of string and chain, which requires judicious manoeuvring to avoid. I reckon we use warps and fenders in about 30% of exits. Thrusters would be no use at all.
 
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