Temporary electric bow thruster on a cat?

[Thalas]

I saw this recent picture of a bow thruster on a Lagoon. While I can't imagine personally wanting to deal with the maintenance and potential failure for the amount of use it would get, there HAVE been times when docking to winward where it would have been nice to have the bow being pushed into the dock.

I was looking at the electric outboard motors for dinghies which supposedly generate 8hp equivalent as a backup for a gas outboard, but wondering if it could do double duty if temporarily mounted on the bow in a transverse configuration on the rare occasion where it's needed in a tricky docking situation.

Has anyone tried a setup like this?

[BigBeakie]

Mounting it would be a challenge. I tried an e-Propulsion Navy 6Kw last week, and its got plenty of grunt. Two of us in 3.5 m aluminum bottom RIB planed at 13knots.


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[valhalla360]

On a larger cat, the problem is getting a long enough shaft to reach from the deck and get the prop deep enough into the water to get a good bite.

It's not unusual on the newer larger cats to have the deck 5-6' above the water. You'd need some kind of custom design to deploy and store it. By the time you did a halfway decent looking job, it would probably be cheaper to just install a small bow thruster.

When we had out Gemini, I thought about doing it. The deck in only about 3' off the water and it's solid fiberglass, so mounting a standard trolling motor would be easier. They have bow mounted trolling motors with remote controls. When not docking they pull up onto the deck and lock in place but when docking, it's simple to push them down and with the remote controls, you can run them from the helm.

As we were traveling 2-3 times per week and docking in all kinds of conditions, we quickly got pretty good with a single engine and never bothered to follow thru but it would be very reasonable to do it.

[StuM]

Two main issues:

Where do you get an EP outboad with a leg long enough to get from the deck to below the hull?

What sort of mount could you dream up that would be solid enough without being ugly as sin when not in use? And how much would it cost?

(Not to mention "magic horsepower" quoted by EP manufacturers when they tell you that a little EP motor is "equivlent to" 8 HP )

Better to learn how to use twin engines, rudder and a spring line

[Sojourner]

Seems like a few obstacles to overcome for a fairly rare occurrence... if things get so hairy, assuming you have a spare person onboard, drop the dinghy and use it to push your bow in.

[26N80W]

When you have two propulsion systems 20 feet apart you don't need a bow thruster. There will never be a need for a bow thruster which out ways the cost, weight, and complexity of the installation and maintenance of such a system.

[Tornadosailing]

You could just go with this system, in case you have too much money and don't know what to do with it.

https://youtu.be/3z3hLDqczjk

[sailingforfun]

Originally Posted by Thalas

I saw this recent picture of a bow thruster on a Lagoon. While I can't imagine personally wanting to deal with the maintenance and potential failure for the amount of use it would get, there HAVE been times when docking to winward where it would have been nice to have the bow being pushed into the dock.

I was looking at the electric outboard motors for dinghies which supposedly generate 8hp equivalent as a backup for a gas outboard, but wondering if it could do double duty if temporarily mounted on the bow in a transverse configuration on the rare occasion where it's needed in a tricky docking situation.

Has anyone tried a setup like this?

Is there only one bow thruster installed? On port hull? Is that all you need?

[Cadence]

Originally Posted by Thalas

I saw this recent picture of a bow thruster on a Lagoon. While I can't imagine personally wanting to deal with the maintenance and potential failure for the amount of use it would get, there HAVE been times when docking to winward where it would have been nice to have the bow being pushed into the dock.

I was looking at the electric outboard motors for dinghies which supposedly generate 8hp equivalent as a backup for a gas outboard, but wondering if it could do double duty if temporarily mounted on the bow in a transverse configuration on the rare occasion where it's needed in a tricky docking situation.

Has anyone tried a setup like this?

I have thought about it. If you should try please let us know.

[Cadence]

Originally Posted by Tornadosailing

You could just go with this system, in case you have too much money and don't know what to do with it.

https://youtu.be/3z3hLDqczjk

It likes a lot for plumbing and holes in the hull.

I actually looks nice but I'm sure it isn't maintenance free.

[Tornadosailing]

Originally Posted by Cadence

It likes a lot for plumbing and holes in the hull.

I actually looks nice but I'm sure it isn't maintenance free.

It looks very nice. There's a video of installation on a Dufour 46. Single pump for all four corners. On a cat of course you double that. Looks like 3 inch exhaust type hose running all over the boat. Can't imagine how many amps two of those pumps will pull. I think I'll just stick with using the motors 20 feet apart.

[akprb]

Originally Posted by 26N80W

When you have two propulsion systems 20 feet apart you don't need a bow thruster. There will never be a need for a bow thruster which out ways the cost, weight, and complexity of the installation and maintenance of such a system.

This is the answer.

It’s a cat for goodness sake :-)

Nose the bow in if the breeze is up and get a line on then back down.

(Head slap) :-)

[Thalas]

Originally Posted by Tornadosailing

You could just go with this system, in case you have too much money and don't know what to do with it.

https://youtu.be/3z3hLDqczjk

This looks even more complicated than the Lagoon Bow Thruster. Definitely the opposite direction for me. I was thinking if I already had the electric outboard, maybe a buckle that locks into place on the inside edge of the starboard bow to temporarily mount the motor in a transverse position and then maybe some hook halfway down to the waterline on the inside edge that holds the extended shaft in place (left to right, but can freely slide out aft so that it's temporary).

I'm going to look at how the regular shaft on these electrics is integrated and see if I can rig up a detachable solution so that I can have a secondary longer shaft to act as a thruster. I know I want the electric as a dinghy backup so the rest is just tinkering fun.

Y'all are right that two motors 20 feet apart give you great control, but there are instances with windage on the bow where a push up front into the dock would be helpful in shorthanded situations.

[Cadence]

I can see what the OP was suggesting. With a light displacement hull hanging an electric trolling motor off the bow, might work when you need it, in a docking situation.
Stow it when not needed. The power to it may be a problem.

[Tornadosailing]

Originally Posted by Cadence

I can see what the OP was suggesting. With a light displacement hull hanging an electric trolling motor off the bow, might work when you need it, in a docking situation.

Or you could do this:

https://youtu.be/ndWD_I_7hVk