stern thruster idea

R

rjmcnabb

New member
Hi Brats,
I'm always interested in ways to improve docking, and ideas of bow and stern thrusters often come to mind -- but how much can you load on a CD22? An electric trolling motor on the stern/swim platform might work for a stern thruster, but at the bow the geometry would be tough to work with.
Another idea I am noodling right now: :idea: what can be done with water flow from the washdown pump? Idea so far: a short hose to a plastic pipe over the stern fitted with a nozzle that can squirt parallel to the water surface. Clipped to the trailer tie-down eye, it could be swiveled 180 degrees to aim port or starboard and kick over the stern. I have yet to test to see if water flow/pressure is adequate to do the job. I envision it as light, inconspicuous and easily removed.
Any thoughts or experience will be welcome. :?: Thanks.
Rod
 
Rod,

I have owned a 35,000lb boat with a bow thruster and I can attest that considerable thrust is needed. As I recall, it was several horsepower turning a 10" prop. Pushing a CD22 sideways would require a lot less. I don't think a trolling motor or washdown pump would cut it. Like you, I enjoy the
"what-ifs" of boating.

But.... The best way to improve docking, is practice, practice, practice! All the best,
 
I hope I don't sound mean spirited, but a bow thruster on a CD 22? REALLY? I've docked in a variety of windy conditions with the full canvas camper up and with sufficient practice docking can be done without a bow thruster. My sense is that you are talking about adding an unnecessary piece of equipment that will require more maintenance etc.

If conditions are windy (especially wind blowing one off the dock), the key is to come in a little faster than normal so that you can put the boat tight to the dock. Then hit reverse a little harder than normal and be quick with the tie up. I think a key is to have both a bow and a stern line readily available from within the cockpit PRIOR to arrival at the dock. If you have both lines ready, you can generally get the boat tied off pretty quickly without being blown off the dock. Also, if you are well fendered and space permits, you can tie off just a stern or (better yet) a midships line while leaving the boat in gear at idle. This will hold the bow tight to to the dock until you can get a bow line on.

All of the above being said, I can tell you that during my first 1-2 years with the boat, almost every docking was a "thrilling experience" especially with high cross winds. It took a lot of practice to get good at but the most important thing was to configure the fenders and lines appropriately and to get everything ready well in advance of approaching the dock. Once I got things set up properly, docking got a lot easier. Of course, there are still times when I don't get things just right and I can look as bad as anyone. But, with a cool head, I back out and do it again. So I'd echo the other Roger's advice - focus on practicing docking.
 
Rod-

1. Interesting thoughts about using some form of assist for docking! I've often thought about the same topic and various possible solutions.

2. Have to agree with the basic conclusions Roger and Roger presented above. The thrust would be too little (especially in strong winds when you need it the most), and is probably not really necessary to dock the boat.

3. But creative thinking will lead to breakthroughs sooner or later, and, just as importantly, is a heck of a lot of FUN in the meantime, so KEEP IT UP!!! :idea:

CHEERS!

Joe. :teeth :thup
 
Roger and Roger (my name is Roger, too, but I prefer Rod.)
Thanks for the input. I generally boat alone, which complicates everything. For convenience, I tie the ends of bow and stern lines together after I leave the dock, and leave them ready in the cockpit. On return, they come off together in one move, and I have both ends of the boat under control. I can hook them under cleat ends if necessary to stabilize position, then untie them and tie down each one separately. I generally tie down the breast line first, then bow and stern. The main reason I obsess about docking is my assigned slip. I can handle parallel parking and the side tie alright. However, my slip involves a 90 degree starboard turn past a piling with a big steel fitting protruding out at water level, :shock: followed by an immediate (!) 90 degree turn to port into the slip (with the finger pier on the port side of the boat and my neighbour's boat to starboard.) All turning room is cramped; there is little current, but often a significant breeze (most often blowing out of my slip.)
I practice often, but somehow it never works the same way, not even twice in a row. :sad Rod
 
my name is roger as well, wait a minute, no it's not, my names pat. i'm always interested in things that make my life more enjoyable. i could go for a bow thruster, also have a lot of experience boating but wind and current can and will screw up the best of days. check out the vetus bow 25 thruster, 12v system, 55 pounds of thrust, weighs 22lbs, has 200 amp current consumption, cost $1706, can be found at www.jamestowndistributors.com i'll follow this thread and hope one of you guys come up with a plan.
best regards
pat
 
Possibly the shallow draft of a C-d would make a bow or stern thruster less effecient, the tunnel should be well below the water-line.
 
I recently had a stern thruster installed on our new boat. In researching thrusters, I found this solution, www.sideshift.com. This didn't work for me, but it is a way of adding a thruster without having the expense of adding a tunnel.

I'll stay out of the discussion about whether it's overkill on a 22 or 25.
Lyle
 
Once upon a time, seems like long long ago, someone made a stern thruster, very similar the the 'SideShift' but (if I remember correctly) it was simply like a electric trolling motor that mounted sideways on the stern (a real good place for a stern thruster), just below the water line, but just above the bottom of the boat. When underway, as it was above the bottom, it caused no drag.

Also I seem to remember a German Co. that made a thruster system that used 2" nozzles on 4 "corners" of the boat. All 4 nozzles were pressurized by a common jet pump (think PWC) that was mounted out of the way. With the 4 , individually controlled nozzles you could walk side ways, or spin using different combinations of nozzles.

Or maybe I was hallucinating ?
 
There is a good dissertation on the topic here:-

http://www.capsante.com/Pages/thruster.html

Every time I mess up a docking I think enviously of our buddies over on the Nut Tuggers site who regularly land "sideways" but then what's the fun if there is nothing else left to learn?

I can make a lot of practice landings for the $2,000 + it would cost me for bow and stern thrusters.

Which makes you a better seaman?

Merv
 
How about this water jet thruster?

http://www.willdo.nl/index.php?subject=180

I have to admit that I have pondered such a thing for the TomCat. Yes, I know that the T/C doesn't have a lot of draft, and two outboards give plenty of control. I guess I'll find out when I get her in the water.

But, I anticipate I'll be single-handing it most of the time, and the TomCat is a might bigger than what I am used to.

And honestly, it would be a big hoot to do them perfectly sideways dockings. :)
---
mike
 
I have only owned one boat with a thruster, and that was a 32 foot trawler, with large cabin/flying bridge/sundeck and a single diesel. That boat I put in a 5 hp thruster, and it worked well. I have run several boats with stern thrusters, and I didn't think that they added anything which I could not do with a single engine.

You could use a trolling motor as a side thruster on the stern. 46 lbs thrust should suffice to kick the stern around if you have to use one. You can remote many of the larger thrusters; my new cat has an 80 lb thrust trolling motor and it can be easily remoted, BUT it requires 24 volts. These salt water trolling motors (recommended) will set you back $350, on up. You will probably have to put the trolling motor on an outboard bracket as you would for a trolling motor, and set it so that the foreward thrust, is in opposite direction as the backing torque of the main outboard. You can then set up a heavy duty relay to reverse the motor at a fixed speed. You will have to drop it in the water when you come into the marina; not use it in the down position when running fast.

I did a delivary on a 62 foot Morgan sailboat with 2" nozzels and a 4 hp jacuzzi pump for bow and stern thrusters. It was no where as effective as a large prop thruster. A water pump will not give you any appreciable increase in control.

First thing to do, if you have not already done it, is to put a power knob on the steering wheel, so you can spinn the wheel lock to lock as you kick the stern around. (Also known as sucide knobs or brody knobs in cars in the 50's)
 
I found a large ? 18" tear shaped fender at a garage sale. Don't remember the make. I experimented with hanging it at various heights and positions along the bow dockside railing - usually near the back of the railing. For docking: When positioned correctly the large fender can protect the entire bow and docking side up to a 45 degree angle of entry - then use the outboard with stern toward dock and in reverse to bring stern closer.

Its also great set up for leaving a crowded fuel dock - I release all other lines at departure except a short helm station spring line that is not long enough to reach the prop. Loop is on the helm cleat and line goes out to dock and back to cleat. when solo I reach out and loosen the line from boat cleat but hold it firm as i turn engine away from dock and put it in reverse, the boat then pivots stern away from dock on the big bow dockside fender mentioned above with little backward movement - once stern clears boat behind I release the short helm spring line and finish backing out. Once clear bring in the spring line. That big fender moved around to be on the docking side has saved a few scrapes. If tied with clove hitch and keeper half hitch [might try the highway mens knot] I can slide it up the vertical aspect of back railing for when underway then drop it back nearer dock by sliding the knot down the railing near the deck. Same big fender is great for rafting with aircraft carriers and other larger boats. - One detail: be sure the helm spring has a clean release path from dock, so it doesn't hang and remove the cleat or railing.

Jim
 
I second Bob's suggestion of adding a suicide knob. I couldn't believe how much it helped slow speed maneuvering in our 25 to be able to turn the outboard lock to lock quickly.
Lyle
 
Adding a suicide knob has been on my list. Where did you get one that will fit the C-Dory wheel? I tried an Edson, but the Edson attaching hardware doesn't open wide enough to attach to the wheel.
 
Ok the water jet is a neat idea and the over the bow unit I have seen on a bayliner. It worked very well and the owner really liked it. But really a bow thruster in a c-dory??? I have hit the dock a little hard a time or two and been blown away before I could get tied up. My solution to both problems was to go practice some more. I do practice docking every once in awhile. It gives you a reason to be on the boat, like I need one.

But really we cannot expect to be good at docking without practice and we will never be perfect. We as people should not even try to be perfect without being able to except the fact they we are not. I know "what the hell is tom going on about know?" I just see a lot of time and money in life being spent trying to perform without mistake without the time spent LEARNING and PRACTICING due to the self imposed horror of failing. "We fail, thereby we learn" Tom Elliott Nov 24 2009.

So what to do in a wind that is blowing you off the dock? Try tying one corner off to the dock, the stern works best, first. Then use the engine and the pivot point to swing the boat to the dock and let the engine hold it there while you tie off the other line. Did I make that clear?
 
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