Hi Boat Cheat, I find your videos very informative and explanations are excellent. We have a Woods design 27 ft open deck catamaran with an outboard mounted at the aft crossbeam on the centerline. Of course we have two rudders with a tiller (no wheel). We keep it at a dock on a river that has 4meter tides. Therefore often a lot of current. It is quite sheltered so wind has not so much effect. We often have a bigger catamarans forward and aft of us. Docking and departing is no big issue when the current is coming from the front, but much more difficult when coming from aft. I have tried docking with the current from behind and usually give up (turn around, move the fenders over) because the boat gets quickly out of control when trying to stop the boat with the motor in reverse. It is difficult to hold the rudders in the center because as soon as I let go of the tiller it of course goes hard over. I was thinking of finding a way to lock the rudders in the center and only use the outboard. When docking I usually have a choice to turn around and go in with the bows facing into the oncoming current. However when leaving the dock there is normally no choice as the only alternative is to wait for the tide to change. It would be interesting to hear your advice. There are a number of older boats with similar arrangement like a Prout Snowgoose except they have a wheel. I also liked your center cleat first on method except we have no center cleat!
Hi Clay, thanks for your kind words. Sounds like a challenging situation. It sounds as though you have identified a potential solution though… I have looked online for suitable pictures to help me make a suggestion, but am not sure I found the right boat, so excuse me if this is rubbish… does the tiller consist of a long transverse bar joining the two rudder arms, similar to that found on Hobiecats etc? If so, does it pass under the control arm of the outboard? If it does, then it might be possible to get a couple of spigots which clamp onto the tiller arm. These could be placed close either side of the outboard control arm, in such a way as the arm can be dropped between them when required, so that the outboard also controls the rudders. If you are able to link to some pictures it might be possible to design or source something that would suit. That way you could fold the outboard control arm up out of the way when not in use, and then drop it between the spigots when needed. The rudders would then always be aligned with the outboard, and the rudder hard-overs you are have experienced would be prevented. Depending on the arrangement of outboard and tiller it might also be possible to rig lines to the outboard control arm using rolling hitches either side, but this would be a bit of a faff… I would be interested in some images, and maybe I could do a video to address your problem, as I am sure it affects a lot of open-deck cats. Thanks for sharing this.
No centre cleat can be fixed relatively easily - I will sort a video on this one as soon as time permits… a bit of a rush on with a training material production contract at the moment so it might be a few weeks…
I have a difficult berth for my lagoon 46. It has 4 pilings and a dock aft. The challenge is that a channel marker is 30ish feet directly in front of the port piling. Outside of that, 30foot fareway is very shallow. The wind blows on the port side. If I go inside the marker there'd not enough room to swing and if I go outside I run the risk of grounding or the bow blowing over before getting port bow secured. Can I pass that forward port piling and attach a midship line to pivot? Thank you
Sounds like a possibility, but without seeing it I couldn’t swear it would work… but if I have understood correctly it might help to try using just the leeward engine when going in so that you reduce the bow being blown off… depending on the space it might make it more manageable…
Nice video and well explained... one small thing though: it's not the "centre of gravity", it's the "centre of lateral resistance" (or somewhat less correctly "centre of pressure").
Thanks! You are of course correct, but this is a practical simplification… I believe that both CG and centre of resistance/centre of pressure have an influence: CG for inertia, centre of resistance for fluid resistance - and there are two of these of vastly differing effects - water resistance and air resistance, each with different centres - but wouldn’t that make for a complicated video!
Will this work on a Seawind 1160? 2 outboard motors in pods in front of rudders but further towards centreline than rudders. I.e. not directly in line with rudders. Thanks for any help.
I suspect that there will be enough propwash on the rudders to have a very marked effect, but the method for standard catamarans would be more suited if your props are forward of the rudders. It would be worth experimenting in relatively calm water to see how much lateral movement you can achieve…
Hello Boat Cheat, thanks for you very nice video's, I have a question. You did the same video on 29 mrt 2020 . But in this video the rudders are in the opposite position ( to the dock) and in this video to the sea. What is right ?? Thanks.
Hi Geoff, thanks! It works just as well for docking as for getting off the dock. For this configuration of rudder and props, simply turn the wheel fully the opposite way to the way you want the boat to move, and use forward and reverse in the natural sense to make the bow move towards the dock - i.e. the engine on the dock side of the boat in reverse, the other in forward. For standard configuration boats simply reverse the wheel direction and steer fully towards the way you want to move. I used this in a reverse sense a few years ago to get alongside gently with a very strong wind blowing us onto the dock - I was concerned that with the high freeboard we would be blown on hard, and so as the turn on was completed I set up as if trying to come off the dock, and using appropriate power was able to gently arrive as if there was a light breeze. Each boat has different characteristics, so it takes a bit of practice to know the sort of response you will get, bit it’s really worth it.
@@geoff850 Hi Geoff, yes, in a Lagoon 380… works fine. Whether leaving the dock or trying to get onto it, the process is the same: turn the helm the in the direction you want to drift, while in conventional configuration you turn the opposite way. Works fine in both cases… but remember that the stronger the elements, the more power will he needed. I came off a dock against a strong wind in Turkey a few years ago, in a Leopard 44, and had a line on the dock-side aft cleat in case the drift was insufficient to overcome the wind. The guy manning the line said it never looked like it was going to be needed, and the back of the boat moved away from the dock without any delay at all. On that same day we used the same method to arrive gently, using asymmetric drift to counteract most of the wind, so we didn’t arrive on the dock with a crunch.
