Reply
 
Thread Tools Display Modes
 
Old 06-15-2014, 09:18 AM   #1
Veteran Member
 
Rduval's Avatar
 
City: WYC, Port Whitby, Ontario
Country: Canada
Vessel Name: Bonaventure
Vessel Model: Cheer Men PT41 Europa
Join Date: May 2014
Posts: 93
Which Bow Thruster?

I have a 41ft Cheer Men with Twin FL120's. I know many will say if you have twins why do you need a thruster but with a keel starting amidships and a hole Sh#t load of windage forward they are not much help when you've got to dock in a tight slip with a 20 knot wind on the beam, it just blows the bow off.

Anyway, the captain has decreed (and I concur #1) that I buy a bow thruster but I want to get opinions on size, makes, etc.
__________________
Advertisement

Rduval is offline   Reply With Quote
Old 06-15-2014, 09:54 AM   #2
TF Site Team
 
Pau Hana's Avatar


 
City: Seattle, WA
Country: Good Ol' US of A!
Vessel Name: Pau Hana
Vessel Model: 1989 PT52 Overseas Yachtfisher
Join Date: Aug 2012
Posts: 1,647
We're in the same boat, so to speak, and have pretty much decided on the a&e turn Yachtthruster. I understand the pros and cons of external vs internal; despite the internet horror stories, I haven't heard of 1 real world example of an external thruster causing damage to a boat due to a log strike.

Plus, I like the DIY approach, and the lack of 2 4" holes in the hull ...
__________________

__________________
Peter- Marine Insurance Guru & tuna fishing addict!

1989 52' PT Overseas yachtfisher
Pau Hana is offline   Reply With Quote
Old 06-15-2014, 10:00 AM   #3
Veteran Member
 
Rduval's Avatar
 
City: WYC, Port Whitby, Ontario
Country: Canada
Vessel Name: Bonaventure
Vessel Model: Cheer Men PT41 Europa
Join Date: May 2014
Posts: 93
Quote:
Originally Posted by Pau Hana View Post
We're in the same boat, so to speak, and have pretty much decided on the a&e turn Yachtthruster. I understand the pros and cons of external vs internal; despite the internet horror stories, I haven't heard of 1 real world example of an external thruster causing damage to a boat due to a log strike.

Plus, I like the DIY approach, and the lack of 2 4" holes in the hull ...
I was looking at that one as well and I like the simplicity (and relative cost savings) of the install but at 1.8kw, I wonder if it's strong enough to handle my windage.

According to a couple of charts I've seen they seem to recommend 3-4Kw as a mimimum.

Here's a link to Lewmars chart.Lewmars chart
Rduval is offline   Reply With Quote
Old 06-15-2014, 10:02 AM   #4
Guru
 
Capt.Bill11's Avatar
 
City: Sarasota/Ft. Lauderdale
Country: USA
Join Date: Apr 2014
Posts: 5,422
While I don't believe you really need one, if you get one, be sure you get one that is not sized to small just to save a few bucks. Having one that is to weak when you really need it is worse than not having one at all.

While I much prefer hydraulic thrusters, in your case it is more than likely battery operated units you will be looking at.

Vetus, IMTRA, Sidepower, Lewmar, etc all make good units worth looking at. You choice may end up having more to do with who in your area installs thrusters .
Capt.Bill11 is offline   Reply With Quote
Old 06-15-2014, 10:04 AM   #5
Veteran Member
 
Rduval's Avatar
 
City: WYC, Port Whitby, Ontario
Country: Canada
Vessel Name: Bonaventure
Vessel Model: Cheer Men PT41 Europa
Join Date: May 2014
Posts: 93
Quote:
Originally Posted by Capt.Bill11 View Post
While I don't believe you really need one, if you get one, be sure you get one that is not sized to small just to save a few bucks. Having one that is to weak when you really need it is worse than not having one at all.

While I much prefer hydraulic thrusters, in your case it is more than likely battery operated units you will be looking at.

Vetus, IMTRA, Sidepower, Lewmar, etc all make good units worth looking at. You choice may end up having more to do with who in your area installs thrusters .
I was wondering about hydraulic now that you mention it, no batteries to recharge, etc. How are these normally powered? Off the main engine or the genny? Is there a lot involved in installing these compared to an electric?
Rduval is offline   Reply With Quote
Old 06-15-2014, 10:22 AM   #6
TF Site Team
 
Pau Hana's Avatar


 
City: Seattle, WA
Country: Good Ol' US of A!
Vessel Name: Pau Hana
Vessel Model: 1989 PT52 Overseas Yachtfisher
Join Date: Aug 2012
Posts: 1,647
Quote:
Originally Posted by Rduval View Post
I was looking at that one as well and I like the simplicity (and relative cost savings) of the install but at 1.8kw, I wonder if it's strong enough to handle my windage.

According to a couple of charts I've seen they seem to recommend 3-4Kw as a mimimum.

Here's a link to Lewmars chart.Lewmars chart
We're looking at the duplex unit:

Yacht Thruster - Bow and Stern Thrusters Models / Technical
__________________
Peter- Marine Insurance Guru & tuna fishing addict!

1989 52' PT Overseas yachtfisher
Pau Hana is offline   Reply With Quote
Old 06-15-2014, 10:47 AM   #7
Veteran Member
 
Rduval's Avatar
 
City: WYC, Port Whitby, Ontario
Country: Canada
Vessel Name: Bonaventure
Vessel Model: Cheer Men PT41 Europa
Join Date: May 2014
Posts: 93
Quote:
Originally Posted by Pau Hana View Post
Oh yeah, didn't see that one.... That might be an option. I don't think the slim profile would affect boat speed hardly at all.

I just wonder on a trawler with a very pointed entry how that will mount, the flange isn't V shaped from what I've seen.

How much are the duplex units?
Rduval is offline   Reply With Quote
Old 06-15-2014, 11:01 AM   #8
TF Site Team
 
Pau Hana's Avatar


 
City: Seattle, WA
Country: Good Ol' US of A!
Vessel Name: Pau Hana
Vessel Model: 1989 PT52 Overseas Yachtfisher
Join Date: Aug 2012
Posts: 1,647
About 6 grand +/-.

When I checked out the units, the "V" was enough to mate up the hull with little concern.
__________________
Peter- Marine Insurance Guru & tuna fishing addict!

1989 52' PT Overseas yachtfisher
Pau Hana is offline   Reply With Quote
Old 06-15-2014, 03:44 PM   #9
GFC
Guru
 
GFC's Avatar
 
City: Tri Cities, WA
Country: USA
Vessel Name: Beachcomber
Vessel Model: Sea Ray 550 Sedan Bridge
Join Date: Nov 2012
Posts: 2,703
Quote:
Originally Posted by Capt.Bill11 View Post
While I don't believe you really need one, if you get one, be sure you get one that is not sized to small just to save a few bucks. Having one that is to weak when you really need it is worse than not having one at all.

While I much prefer hydraulic thrusters, in your case it is more than likely battery operated units you will be looking at.

Vetus, IMTRA, Sidepower, Lewmar, etc all make good units worth looking at. You choice may end up having more to do with who in your area installs thrusters .
I wholeheartedly agree with his first sentence. When we put our thruster in the bow, I checked the charts and found the one they recommended. The boat yard that did the install recommended upsizing to the next size up. (Both would have had an 8" tube). When he tried to buy that size he couldn't find it so he, on his dollar and with my permission, put in the NEXT size up that uses a 10" tube.

I've never regretted going bigger. When the wind is blowing it's nice to have that extra oomph to move the bow.
__________________
Mike and Tina
Beachcomber 1995 Sea Ray 550 Sedan Bridge
GFC is offline   Reply With Quote
Old 06-15-2014, 03:50 PM   #10
Guru
 
Capt.Bill11's Avatar
 
City: Sarasota/Ft. Lauderdale
Country: USA
Join Date: Apr 2014
Posts: 5,422
Quote:
Originally Posted by Rduval View Post
I was wondering about hydraulic now that you mention it, no batteries to recharge, etc. How are these normally powered? Off the main engine or the genny? Is there a lot involved in installing these compared to an electric?
You can run them off a hydraulic pump mounted either to a main engine or your Genset. Or you could use a hydraulic power pack setup where the pump is AC powered and the pack is mounted near the thruster perhaps.

The nice thing about hydraulic thrusters is you can run them for as long as you like without worrying about them timing out due to the motor over heating. And the inherent reliability of hydraulics.

But on a smaller boat a battery operated system where the batteries are located near the thruster may be cheaper and easier to install.
Capt.Bill11 is offline   Reply With Quote
Old 06-15-2014, 05:26 PM   #11
Veteran Member
 
Rduval's Avatar
 
City: WYC, Port Whitby, Ontario
Country: Canada
Vessel Name: Bonaventure
Vessel Model: Cheer Men PT41 Europa
Join Date: May 2014
Posts: 93
Quote:
Originally Posted by Capt.Bill11 View Post
You can run them off a hydraulic pump mounted either to a main engine or your Genset. Or you could use a hydraulic power pack setup where the pump is AC powered and the pack is mounted near the thruster perhaps.

The nice thing about hydraulic thrusters is you can run them for as long as you like without worrying about them timing out due to the motor over heating. And the inherent reliability of hydraulics.

But on a smaller boat a battery operated system where the batteries are located near the thruster may be cheaper and easier to install.
GFC: I agree, better to have too much than not enough.

Capt Bill: The AC powered hydraulic power pack sounds interesting. We have our queen bed in the forward stateroom right over the thruster and there is a ton of room in there. Getting AC to a hydraulic power pack under there would be a breeze. Plus she does sit a little bow high at the moment and a bit of weight up there would certainly help things.

Has anybody used an AC hydraulic pack? Can you recommend brands?
Rduval is offline   Reply With Quote
Old 06-15-2014, 05:43 PM   #12
Veteran Member
 
Rduval's Avatar
 
City: WYC, Port Whitby, Ontario
Country: Canada
Vessel Name: Bonaventure
Vessel Model: Cheer Men PT41 Europa
Join Date: May 2014
Posts: 93
Wow, a quick online check seems to show that hydraulics are WAY more expensive than the electric DC systems. On the order of 3 to 4 times more expensive!
Rduval is offline   Reply With Quote
Old 06-15-2014, 05:51 PM   #13
Guru
 
twistedtree's Avatar
 
City: Gloucester, MA
Country: USA
Join Date: Jan 2013
Posts: 3,202
Instead of an AC hydraulic pack, you might be better off with a PTO mounted pump on your generator. Either way you will be running the generator, adn direct PTO power eliminates the losses associated with generating and then consuming electricity.

You will need to run the numbers for hydraulic capacity to see what you need. A big advantage to a pump on the generator is that it runs at 1800 RPM. In contrast, a pump on the main engine running at idle will produce far less flow per CC of pump size.

I've got pumps on both the main and generator, and either can power one thruster up to full power, but it takes both pumps to power both thrusters at full tilt. The main engine pump is huge, and even then only drives one thruster at idle. The bottom line is that they take a lot of power, and it needs to come from somewhere.
__________________
www.MVTanglewood.com
twistedtree is offline   Reply With Quote
Old 06-15-2014, 06:01 PM   #14
Guru
 
Conrad's Avatar
 
City: Calgary
Country: Canada
Vessel Name: Blue Sky
Vessel Model: Nordic Tugs 42 Hull #001
Join Date: Oct 2007
Posts: 1,553
Our bow thruster is anemic at best; good only for a very slow push away from the dock under low/no wind conditions; to use it with any conviction during typical docking manoeuvres would provide standing room only entertainment for the dock crowd.
If we do decide to upgrade, the big question - aside from manufacturer - will be to determine whether we go 12v or 24V. Both approaches have their pros & cons from what I can tell.
Since it hasn't been mentioned in this thread, I wonder what the thoughts might be?
__________________
Conrad
Berthed in
Campbell River BC
Conrad is offline   Reply With Quote
Old 06-15-2014, 06:20 PM   #15
Guru
 
twistedtree's Avatar
 
City: Gloucester, MA
Country: USA
Join Date: Jan 2013
Posts: 3,202
Quote:
Originally Posted by Conrad View Post
Our bow thruster is anemic at best; good only for a very slow push away from the dock under low/no wind conditions; to use it with any conviction during typical docking manoeuvres would provide standing room only entertainment for the dock crowd.
If we do decide to upgrade, the big question - aside from manufacturer - will be to determine whether we go 12v or 24V. Both approaches have their pros & cons from what I can tell.
Since it hasn't been mentioned in this thread, I wonder what the thoughts might be?
with 24V more power is possible, smaller cables are required, and you will have smaller resistive power losses. High power devices like a thruster is where 24V can really make a difference. The down side is that you will need some sort of dedicated charger
__________________
www.MVTanglewood.com
twistedtree is offline   Reply With Quote
Old 06-15-2014, 06:55 PM   #16
Guru
 
Steve's Avatar
 
City: Thibodaux, Louisiana
Country: USA
Vessel Name: Gumbo
Vessel Model: 2003 Monk 36
Join Date: Oct 2007
Posts: 3,607
We have had 2 trawlers, both single with bow thrusters, the first a Camano with Sidepower, and the current Monk 36 with Vetus. I have not had problems with either. In both cases the bank of batteries ran the house, windlass, thruster, and started the main engine.
__________________
Steve W.
http://mvgumbo.blogspot.com/
Steve is offline   Reply With Quote
Old 06-15-2014, 06:56 PM   #17
Guru
 
Insequent's Avatar
 
City: Brisbane
Country: Australia
Vessel Name: Insequent
Vessel Model: Ocean Alexander 50 Mk I
Join Date: Mar 2012
Posts: 1,426
I went with the largest Lewmar in 12V, 8HP. Usually its enough, and a lot of the time I don't even need to use it at all. But for the times when it isn't enough I really regret not going for a larger 24V unit. For the OP, that 8HP unit might well be enough. I would just say that if you are going to the trouble of installing one, don't scrimp, go large.

Power for mine is 4x12V AGM's up in the bow next to the thruster. It would have been easy enough to have a 24V charger dedicated to keeping them charged, no need for an elaborate 24V system addition.
__________________
Brian
Insequent is online now   Reply With Quote
Old 06-15-2014, 07:01 PM   #18
Veteran Member
 
Rduval's Avatar
 
City: WYC, Port Whitby, Ontario
Country: Canada
Vessel Name: Bonaventure
Vessel Model: Cheer Men PT41 Europa
Join Date: May 2014
Posts: 93
I was reading another thread earlier where they said they used an "echo charger" that ran off their 12v bank to charge their 24v bank.

Is it true that AGM batteries are safe to put in unventilated enclosures (like under my bed)?
Rduval is offline   Reply With Quote
Old 06-15-2014, 07:36 PM   #19
Senior Member
 
On The Rocks's Avatar
 
City: Palm Springs CA
Country: USA
Vessel Name: On The Rocks
Vessel Model: Gulf Star MKII
Join Date: Apr 2012
Posts: 109


I went with the extern, it works really well. You should go at least one size larger than they recommend. The yard that did the install had to fabricate a pad for it to mount to because the V on the keel was too sharp for the adapter they make. Be careful with the paint the yard uses, it has to be safe for aluminum. Mine was painted with the wrong paint and it caused electrolysis so all the paint has blistered off and I'll need to have it hauled and re-painted.
On The Rocks is offline   Reply With Quote
Old 06-15-2014, 07:45 PM   #20
Senior Member
 
On The Rocks's Avatar
 
City: Palm Springs CA
Country: USA
Vessel Name: On The Rocks
Vessel Model: Gulf Star MKII
Join Date: Apr 2012
Posts: 109
Click image for larger version

Name:	ImageUploadedByTrawler Forum1402875616.157125.jpg
Views:	137
Size:	93.1 KB
ID:	30566

Sorry didn't get the picture in the last post. Alex at yachtthruster is great to work with by the way. There are more pictures of my install on thier web page. I did a stern thruster too just for fun. I can do 360s in the fairway no problem. 😜

Click image for larger version

Name:	ImageUploadedByTrawler Forum1402875904.806331.jpg
Views:	421
Size:	152.7 KB
ID:	30567
__________________

On The Rocks is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 04:40 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012