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Discussion Starter #1
Greetings from Finland,

I would like your comments and feedback on a project I have been working on. I have been building a motorised mechanism for lowering a Sideshift stern thruster into the water, from under the swimming platform on my Malö 43 sailing boat. Please see the below youtube video of how the mechanism works.

I posted a short youtube video here:
https://www.youtube.com/watch?v=RpIoVC_h7WU

Any thoughts and comments are most welcome!

Kind regards
Jarmo M.
Finland
 

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Discussion Starter #3
This is a mk 2 version of the lowering mechanism, which is yet to be tested. However the stern thruster itself I have been using for 5 years now, with great success. The thruster is a Side Shift 12V, it's a bit underpowered for this size boat (43'), but other than that it works perfectly :)
 

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Master Mariner
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The only reason one would need a stern thruster on a small craft is if there was no water from the prop passing over the rudder.
Turn the helm hard over and give the engine a good, quick burst of power, and voila, the stern goes sideways.
 
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Catalina 400 MKII
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Putting aside the opinions of what size boat to use it on, the basic idea looks great. Very innovative! Takes care of many issues surrounding having a thruster that "lives" in the water.
 

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Need is relative for thrusters, but if they were free, really.... who wouldn't want one?

Some thoughts I have:

1# looks nice.
2# Make sure it is robust enough that if (read: when) the owner leaves it down it won't break after sailing with it down at hull speed all day.
3# How do you think the prop wash will affect its thrusting ability?
4# Swim steps are becoming less common in favor of sugar scoops and open transoms. You may need several mounting options if you want a broader market.
5# Send me one to test! I love thrusters! :D

MedSailor
 

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PS. It's nice to hear from Finland. My boat hails from there and when we had the rigs down we put up some Finnish flag stickers on the top of the main mast.

Any other boats in Finland with Saunas? I hear they're popular up there.

MedSailor
 

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Yea, I know we like to give thruster guys a bad time; however, I confess to having one when we had a boat in the 50's, and liking it.

This idea totally gets rid of the hole in the boat issue; however, it only works on the stern, which is the only part of the boat that's relatively controllable conventionally as Capta has pointed out.

I'm also worried if it's powerful enough to make a difference. I found that even a big built in thruster was no match for a big cross wind.

But hey, very creative...might lead someplace. To the OP, good luck! Add it to Med's boat, rumor is he's got a sauna too:D
 

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Super Fuzzy Moderator
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I'm also with Capta. Our Malo is the smaller 39Classic and is fitted with a bow thruster. I confess that prior to owning one I'd not considered them but having lived with it I've learnt to love it, though I still feel some embarassment about using it. Than again I feel much the same about motoring up to a mooring and the fact I drive an auto not a stick shift. :eek:

That said I have never felt the slightest need for a stern thruster though maybe in Europe the conditions are so different that such a thing has an application. By conditions I'm thinking of the necessity for tying up stern to a seawall where space to manoeuvre is severely restricted by boats either side.
 
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Greetings from Finland,

I would like your comments and feedback on a project I have been working on. I have been building a motorised mechanism for lowering a Sideshift stern thruster into the water, from under the swimming platform on my Malö 43 sailing boat. Please see the below youtube video of how the mechanism works.

I posted a short youtube video here:
https://www.youtube.com/watch?v=RpIoVC_h7WU

Any thoughts and comments are most welcome!

Kind regards
Jarmo M.
Finland
Jarmo Sailnet has it's share of Luddites, don't let them bother you! :D

It's an interesting design (actually your whole swim platform design is interesting).

It's hard to judge size on a YouTube video. I'm guessing the thruster is approx. 30cm deep when deployed?

If you flipped the bracket that mounts to the tubing front to back; and lengthened the down tubes it looks like you could pick up another 15cm of depth - again tough to estimate size on the video. I'm assuming the tubing is ~2.5cm.

My thought is the extra depth might give you a bit more bite in the water.

Also would a stiffening plate between the down tubes prevent side flex and help put more of the thruster's output into the water?

FWIW, I wouldn't mind seeing some more photos and comments on the design of that stern platform. It looks like there are some good ideas there.



Jim
 

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This concept seems like a solution looking for a problem to solve. The key thing to understand about a thruster is it only serves to rotate a boat, it does not move the boat sideways. You prop wash over an angled rudder has the same effect, plus the chance of some forward movement...

The mechanics of this stern thruster would be such that it has no effect different from a bow thruster, it serves to rotate the boat. Should you feel the need for a thruster to assist in your boat handling, then the bow would seem a much more convenient place, and for a fixed installation.
 

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HANUMAN
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Very nicely done.

I'm sure it will be a big help when in a tight med-mooring situation!

We don't do that in my part of the world; so the concept of anchoring while backing into a tight spot under the watchful eye of dozens of drunk German tourists, most of the men in speedos, is terrifying. :)
 

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OP posted 2 times and that was that.
Meh. It's only been a day. Not all of us have day jobs that keep us tied to the computer with SN to keep us sane. :)
 

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One of None
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True Donna.. and us retired folks need something to do when we aren't selling a boat LOL
 
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