Jump to content

Bow Thruster Size


Lizzie123

Featured Posts

I am happy to fess up that I once used a bow thruster on a family member's boat.

 

It was during a reverse manouevre to get back to a water point about 1/4 mile from where he had moored. Now I know some boats reverse better than others but the prop walk seemed particularly noticeable on his boat.

 

Cue the 'cissy' button. It was tbh a bit of a revelation to be able to do the manoeuvre in one. Without the need to pause, correct in forward, reverse, pause, correct in forward, reverse and so on.

 

 

Link to comment
Share on other sites

On 05/08/2020 at 08:58, Alan de Enfield said:

Indeed it has, but as this is the OP's first post on the forum I doubt she is aware of previous discussions.

 

I still stand by my point that a BT is useful &, I still stand by my point that you should be able to steer the boat without a BT as one day it will go wrong.

Have read through previous discussions, not greatly useful as very mixed. As with all boat handling experience is always best but in terms of having the best resources as the boat is new and has yet to be placed in the water it would be easier to fit BT now...

 

Have experience just not with something this size.

Link to comment
Share on other sites

5 minutes ago, Lizzie123 said:

Have read through previous discussions, not greatly useful as very mixed. As with all boat handling experience is always best but in terms of having the best resources as the boat is new and has yet to be placed in the water it would be easier to fit BT now...

 

Have experience just not with something this size.

 

If you want to be sure the bow thruster is capable of moving the boat in the majority of wind conditions then you need the highest output available. The lower the output the less wind it can counter. So the answer to the question is the largest that will fit/you can afford.

Link to comment
Share on other sites

1 minute ago, Tony Brooks said:

 

If you want to be sure the bow thruster is capable of moving the boat in the majority of wind conditions then you need the highest output available. The lower the output the less wind it can counter. So the answer to the question is the largest that will fit/you can afford.

Ok thank you. That is very useful, think we are constricted slightly by tunnel size put in by boat builders.

Link to comment
Share on other sites

If it helps 5Kw equates to about 6.5 hp while 6Kw is about 8hp. A full length narrow boat at canal seed probably demands about 6hp but the side of a wide beam narrow boat is like a big sail in wind. I know that in afresh breeze sideways on I can't pull a 54ft boat alongside in the marina and have to resort to taking a full turn and a half around a bollard and then "swinging" the boat alongside. Swinging is where you pull/push as hard as you can on the length of rope between bollard and boat and as you ease off pulling the slack in with the other  end of the rope. However Its easier to do it with a spring line and engine as is springing the bow off the marina services wharf. Its difficult to spring off from the bank side in most places. Learning the techniques and other handling on the lines methods are always useful and its why a number here have suggested you don't really need a bow thruster but for occasional use, usually in wind, a bow thruster makes life easier for new or inexperienced boaters.

Link to comment
Share on other sites

12 minutes ago, Halsey said:

Vetus - its like buying Victron quite simply quality is always worth paying for - if you can afford a good one I would rather go without 

Personally I am not convinced Vetus stuff is quality, expensive for what it is yes giving perceived quality maybe but not out and out quality above many others.

Link to comment
Share on other sites

I fitted an electric 4hp BT on Innisfree, when I tested it in a marina finger mooring I was unable to hold it back with the bow line and I am, or was, a strong bloke. But in a crosswind, though it could push against it, overheating would cut it out after 15-30 seconds or so and then the wind would push it back.. Bigger electric ones will still overheat but they have more chance of completing the task in the time before they cut out. 

Link to comment
Share on other sites

On 08/08/2020 at 21:29, The Gravy Boater said:

I can attest that bow thrusters are entirely useless in a strong wind, with or without experience.  They are of most use when reversing onto stuff, or straffing in calm weather.

 

That's my experience too. I guess it might depend on the power of the thruster. I've seen a gravel barge with a thruster more powerful than most of our boat engines, but the thrusters on most canal boats aren't going to help much in high winds or currents.

On 13/08/2020 at 16:18, Tony Brooks said:

Personally I am not convinced Vetus stuff is quality, expensive for what it is yes giving perceived quality maybe but not out and out quality above many others.

 

I'm happy with the quality of my Vetus, but it came with the boat. If I was choosing one I probably wouldn't choose Vetus. Aren't Noble supposed to be good?

Link to comment
Share on other sites

On 13/08/2020 at 16:02, Tony Brooks said:

... but for occasional use, usually in wind, a bow thruster makes life easier for new or inexperienced boaters.

 

Forget about wind - bow thrusters on canal boats aren't designed to counteract high winds.

 

For occasional use, a bow thruster makes like easier for experienced boaters too!

Link to comment
Share on other sites

13 minutes ago, blackrose said:

 

That's my experience too. I guess it might depend on the power of the thruster. I've seen a gravel barge with a thruster more powerful than most of our boat engines, but the thrusters on most canal boats aren't going to help much in high winds or currents.

 

I'm happy with the quality of my Vetus, but it came with the boat. If I was choosing one I probably wouldn't choose Vetus. Aren't Noble supposed to be good?

I have a Vetus 50 (55?) I think there is also a 75 model.  It has its uses in calm weather but it can also be a distraction.  Never try and fix an evolving problem with a bow thruster, even in calm weather.  If you're in a bad situation it's better to just stop, reverse, remove all momentum from the boat and start again.

Link to comment
Share on other sites

On 09/08/2020 at 11:31, Richard10002 said:

Vetus use Kgf to describe their bow thrusters, whereas the OP is being offered a choice between a 5Kw and a 6Kw bow thruster.

 

This thread tries to clear up some confusion.... kgf seems to need some m/s to compare directly with kw:

 

 

there is no direct comparison - it's like trolling motors which are commonly referred to by lbs thrust, which cannot be directly related to a petrol outboard rated in h.p. by any valid scientific method.

 

I do know that a 75kgf Vetus draws about 4kW power.

 

useful link:

https://www.navstore.com/vetus-how-to-size-bow-thrusters.html

 

Link to comment
Share on other sites

On ‎04‎/‎08‎/‎2020 at 16:28, Alan de Enfield said:

 

 

YES, you can handle a widebeam without a bow thruster, it just takes practice.

I currently have  one boat with a 14 foot beam and another boat with a 23 foot beam - neither have (or need) a bowthruster.

 

Good luck.

But do you have two engines to drive them?

Link to comment
Share on other sites

On 13/08/2020 at 16:04, Halsey said:

Vetus - its like buying Victron quite simply quality is always worth paying for - if you can't afford a good one I would rather go without 

I have a Vetus on my boat,,,, not sure what to do with it as bow tube is welded over.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.