Was Told I Need Bigger Rudders

[sunchaser]

On my 45 ft Bluewater Coastal Cruiser I was told that I have high speed rudders and that's why it is hard to dock or control at low speed..

Who told you this and why?

 

[psneeld]

For many gassers I have heard the same comment and can't say it's too far off the mark.

While certainly not true of many high speed gassers, enough have that charachteristic that are dogs at docking...so its the logical go to explanation.

 

[kchace]

For many gassers I have heard the same comment and can't say it's too far off the mark.

While certainly not true of many high speed gassers, enough have that charachteristic that are dogs at docking...so its the logical go to explanation.

In the winters with the boats on the hard around here its easy to tell the "high speed" boats from the slower ones looking at the rudders and props. Lots of pitch/small rudders - higher speed boat, and its amazing (to me) just how small some of those rudders are.

Ken

 

[kchace]

I would love bigger rudders. They are so lethargic even at my 8.5 it cruising speed. I would definitely like larger rudders someday.

When docking, idling the engines and using forward and reverse only isn’t enough. I often have to use at least 1000 RPM in both forward and reverse to really make anything happen or to overcome any kind of wind. I do bring the engine to idle before shifting, then bring the rpm back up again if need be.

I’ve been told 1200 rpm is safe in reverse. Is it the prop or the transmission that doesn’t like much rpm in reverse?

You can use as much rpm in reverse as you want. It doesn't hurt anything, what you want to try not to do is shift from forward to reverse at higher rpms and to pause in neutral (if circumstances allow) between forward and reverse. But in critical situations you do what you have to do.

Ken

 

[kchace]

When in idle (3kts) I have very little control with the rudders. This makes maneuvering in tight marinas more stressful than I feel it should be.

My old marina was tight. I feel like riddlers should be able to control the boat in idle. For me the most part they do, but I would often have to use two full turns on the wheel to make a slight correction. And even still I’d have to use power or transmission to help.

Do you have a rudder indicator? Do you have an adjustable helm pump? In other words, is there a knob sticking out under the steering wheel shaft? If so, it may be adjusted so that it takes many turns lock to lock. So you may not be moving the rudders as much as you think. If you do have this setup and you want to make the steering quicker, "tighten" the knob. It takes a few turns to make much difference. I would suggest turning it in all the way (until it stops) that should make the lock to lock steering about 3 or so turns.

Ken

 

[steelydon]

Obsession is single engine w/ bow/stern thrusters. I agree there is no substitute for experience and finding an unused dock to practice touch and go's can provide invaluable experience. I would say my rudder is a moderate size and the handling in both forward and reverse was less than ideal. I added a stern thruster when I bought the boat and made the mistake of going with the lowest recommended size. Additionally, the bilge is so shallow in the stern that the thruster cavitated during use further compromising its effectiveness. The thrusters will not overcome current much above 1kt or winds over 15mph. Getting to know the handling characteristics and prop walk of your boat is critical. The only way to do that is getting out there.

I did fabricate some wings this past summer to add to my rudder and a friend fabricated some caps for the thruster. The wings improved forward steering 40-50% and the thruster caps eliminated the cavitation. I attached pictures to show the work and rudder size.