Bow Thruster Installation/Use

[The Dog House]

Dog House, we talked awhile back about all this spring line docking you do, and I mentioned that I had a Silverton 26 prior to my first Trojan F32, sold it to a friend, shes still around, reading the comments the depth of this thruster may be a issue but let me ask you is it worth the investment to these older boats? Those stern thrusters I believe are much lower priced and should help with the prop wash, I dock my Silverton in varying conditions, and back out of some tight slips, just need to be fast with gas/transmission and commit/know how the boat will react

In 5 to 10 years my bow crew (wife) will be retiring from bow work. Maybe I'll be good enough by then to handle the wind/current I'm currently facing without a spring line, but at my current skill level I'm not good enough to put my boat between two other boats that have more than 10 foot beams with only a few feet extra on each end of the dock space. If my skills do not improve by that time, I'll have three choices: get a bow thruster (~$8,000), get a different boat (~$50,000), or get a different wife (much more than $50,000). I bought my boat for $3,000 and put another $6,000 into her for a total cost of $9,000. Another $8,000 would only get me up to $17,000, which is much less expensive than $50,000. If I'm confident that my current boat will be reliable, $8,000 for a bow thruster is not unreasonable to save me from spending $50,000 to buy a different boat. It's not only the cost of the purchase, but also the cost of the alternative that needs to be considered.

[ready123]

Here's another link that gives some good info.
http://dunncruisingguide.com/ddunn/BoatHandling.htm

I'm currently using the "Docking With A Bow Line" and "Aft Spring Line" techniques described in this link. They work very well for when the wind is blowing the boat off the dock for docking and onto the dock when leaving the dock, respectively. All other times I don't find it necessary to use a spring line.

So am I to conclude that when there is no wind you are able to dock without a spring line?
If that is in fact the case then it would seem to me that you need more throttle to remove/reduce the effect of the off dock wind that seems to force you into a steeper approach.
I still don't understand why your wife can't use the docking stick to place the spring line from the cockpit. Using a longer line +3 feet if necessary and moving the dock cleat back same amount should work fine. Yes, you will have to change your approach to be shallower than you do now with her on the bow and maybe add some rudder with a little bump of throttle at the last minute to pull the cockpit closer to the dock...... angle should be similar to when you dock without a spring but with more throttle to offset wind pressure.
Nothing you have said here causes me to change my stance that a change in technique can achieve your wife handling a spring line from the cockpit..... and save the bow thruster costs.

[P-Dogg]

This is hardly the first thread where "real" boaters have bad-mouthed bow thrusters. The fact of the matter is, regardless of how awesome your technique is, bow thrusters make your boat more maneuverable.


Remember when anti-lock brakes came along? And airbags? People bad-mouthed them as unnecessary. The fact of the matter is, they increase safety. The same holds for thrusters. They give you another card to play, and increase your options. If you're thinking that a bow thruster would reduce anxiety, or increase safety, or let you boat longer, or single-handed, or enable your wife to dock the boat, then by all means install one.

Over coffee this morning I happen to read the section on thrusters in Calder's Boatowner's Mechanical and Electrical Manual. It's worth a read if you haven't been there yet.

[captainmaniac]

[quote="ready123"What was your fuel consumption on that trip to Kingston from Burlington??[/quote]

Don't mean to hijack the post... but just wanted to answer the Q... Cruise speeds varied a lot throughout the trip, but overall averaged about 1.1 nmpg over about 440 miles. At each fuel stop we got anywhere from 0.96 to 1.3 nmpg. Total trip was from Hamilton down as far as Rockport in the St. Lawrence, and return, with stops at Cobourg, Trenton (new marina is nice!), Collins Bay, Gananoque, Ivy Lea, Kingston, Picton, Cobourg, and Toronto Island. We were away for 2 weeks, really need 3 to do the trip justice. When I no longer have to work for a living, maybe we can spend a LOT more time in the islands. Wanna try Georgian Bay / 10,000 Islands at some point.

Much of our time on Lake Ontario was in sub-optimal conditions (3-6' on the stbd aft quarter while heading east from Hamilton to Presquile - lots of surfing and fighting the wheel when the bigger ones picked us up and threw us into the back of prior waves, and again 3-6' very close together (wavelength maybe 50-60') on the bow while heading west from Presquile to Cobourg - so pretty tough slugging that made me slow to 10-12 knots to keep pounding under control). Plus we had really strong head winds while going south on Long Reach, and west on Adolphus Reach. Our trip east on Lake Ontario just so happened to be Aug 2 - when one heck of a storm went through. http://www.cbc.ca/news/trending/ontario ... -1.3177494 http://www.theweathernetwork.com/uk/pho ... m/23052274. Reports were that storm winds hit almost 60mph in Toronto.

The leading edge of the storm caught up to us about 2 minutes before getting in to Cobourg, and then we were hit with its full fury about 10-15 seconds after rounding the breakwall and getting into the lagoon. Had to wait it out on the flybridge and hold the boat in position for 10-15 minutes until winds and rain died down enough to move towards the docks and get into our slip... I was soaked to the skin in about 2-3 seconds. Even with bimini over my head - no more than 6" above me, and front edge 4' in front of me, I was still being pelted in the face with rain. Even wearing glasses, my eyes were stinging. The rain was just going sideways... Thought we were going to beat the storm up until 5 minutes out of Cobourg -- had been looking over my shoulder every 30 seconds for the last half hour, and up to that point I could see shoreline 10-20 miles back, so knew the storm wasn't over the water yet. The next time I looked, shoreline was starting to disappear. Crap. That's when the throttles got shoved up to 3200 RPM (24 knots) in spite of the aft quarter wave action... Didn't quite make it!

Over the trip, we ran at 800-900 RPM (Murray Canal) - about 5 miles each way, sometimes 1500 RPM (slow cruise around the Islands), around 2150 RPM (running in to very close 3-6 footers from Presquile to Cobourg), and roughly 2800-2900 RPM (18-21) for most other legs where we had open water and conditions conducive to those speeds.

[ready123]

This is hardly the first thread where "real" boaters have bad-mouthed bow thrusters. The fact of the matter is, regardless of how awesome your technique is, bow thrusters make your boat more maneuverable.
Remember when anti-lock brakes came along? And airbags? People bad-mouthed them as unnecessary. The fact of the matter is, they increase safety. The same holds for thrusters. They give you another card to play, and increase your options. If you're thinking that a bow thruster would reduce anxiety, or increase safety, or let you boat longer, or single-handed, or enable your wife to dock the boat, then by all means install one.
Over coffee this morning I happen to read the section on thrusters in Calder's Boatowner's Mechanical and Electrical Manual. It's worth a read if you haven't been there yet.

I don't see anyone bad mouthing thrusters..... they work and make life easier if they have the correct power for the application (prop size and battery power). Good one's (in hull) likely can't be used on an F26 hull
My point is that the cost effectiveness to deal with those real windy off dock days means it needs to be big enough both prop diameter and battery size.
So how do you do it on an F26? Not the best boat to add one to.
One of the one's that fit on the exterior of the bow and slide down underwater for use, open to damage and downright ugly when above the waterline... where is the heavy battery placed? Further away from the bow heavier gauge run of power cables means $$$.
Another charger to keep the battery up maybe? Does all this expenditure to have something that really works worth it?

A lot of negatives there to reduce the performance of an F26.......... all I am saying is that change in technique can get the job done without the $$ impact and lowered performance of the modified F26.
We also have not touched on the advantage of a 4 blade prop for low speed maneuverability also helping, is the boat being docked on the side where prop walk is a benefit? It's not like an F26 has extreme profile to create high wind resistance.
The owner will do whatever makes him happy.... I'm suggesting that a specific technique change can get the job done surprisingly well.

[prowlersfish]

Sitting back watching this post . I have been silent and have posted against bow thrusters in the past . But most of those cases have been newbies looking at boats like the F25 or F26 . In many cases its not needed , just need to learn how dock the boat and quickly work the lines ( key word quickly ). I never had the need but the single screw boats I ran were heavy and had big wheels (and Power ) . I am not one to use lines to dock , as I single hand dock a lot, so I have to get the boat where it needs to be and get the lines on . Having twins helps a lot .


But there are different cases where a thruster would be a good idea. As in Dog house's case . As I said I single hand a lot docking , its not that I boat alone a lot . My better half can not move around the boat quickly . Her reaction time is not fast and like me she is not getting any younger or faster so using spring lines to dock are not a option in most cases . I suspect Doghouse's case is similar to mine and has the disadvantage of a single screw .

Add the fact that the wind and current can quick spin a lighter boat around . A Bow thruster seems to be the best and maybe the only realistic choice .

[lawyerdave71]

There is another alternative solution which many may have overlooked . . .

you could get a new younger wife!!!!!!

IM KIDDING KIDDING KIDDING

[prowlersfish]

There is another alternative solution which many may have overlooked . . .

you could get a new younger wife!!!!!!

IM KIDDING KIDDING KIDDING

Leave it to a Lawyer

[larryeddington]

Then you could not afford another boat as the old wife would have the current one.

[prowlersfish]

Then you could not afford another boat as the old wife would have the current one.

And the money to buy the next one