R-25's rudder and increasing its surface area

[baz]

I believe most R-25 owner will attest to there being little rudder action at low speeds of less than 2-3 knots. The rudder is very skinny and has but 7-8" of horizontal surface.

A buddy who keeps his R-25 just a few slips away from me at my Marina took the plunge after finding the rudder has little affect at low speed. He bolted a plate to the rudder to increase its surface area by a factor of 2. He claims it makes a huge difference at around 1-2 knots and helps him dock with ease without the use of the thrusters.

Has anyone else made a similar modification to the R-25's rudder ? If so, what was the result ?

 

[PhilR]

I suspect that Ranger Tugs would not look favorably on this modification from a warranty standpoint. Also, I have found that the trick to quick response to the rudder at slow, forward speeds is to turn the wheel and deliver a short "burst" of power....works every time.

Phil

 

[abcandjrc]

.......Also, I have found that the trick to quick response to the rudder at slow, forward speeds is to turn the wheel and deliver a short "burst" of power....works every time.
Phil

A key to success with single screw boats. It also pays to determine which way the stern "walks" if you give a burst in reverse since the rudder has little effect at 0 speed in reverse. But with practice one can back into a slip, even at slow speed.

I would also suspect that increasing the rudder area might create a hazardous overly-quick steering at high forward speeds. And those are the types of accidents that kill people. Bumping a pier at 2 mph rarely does.

 

[jroyle]

Modifying the surface area of the rudder is a very bad idea. The handling response at higher speeds is going to be very unsafe and the increased pressure on the rudder/shaft bearing is going to lead to premature wear and failure. These boats are designed with the proper prop/rudder dimensions so why mess with it :?:

 

[baz]

Wow -- thanks much for that alarming news... I will surely pass this info along to my dock mate.

I must admit I was concerned about the rudder mod especially considering Ranger Tugs has not seen any reason to change the rudder design knowing its low speed affects... hence the reason for thrusters being standard stock with these R-25s.

jroyle: Thanks again for the warning.

 

[trailertrawlerkismet]

I agree with jroyle that to take on a rudder modification on your own is not the best idea, unless you are a naval architect. With that said, if one is interested in making improvements, I'd suggest talking with Ranger Tugs directly to ask if they'd have a recommendation for a larger rudder to help at slow speeds. The disadvantage, as spelled out earlier, is a larger rudder increases steering sensitivity at higher speeds and therefore can be dangerous with to large a rudder.....therefore the reason for talking with Ranger Tug. Another option to get their opinion on would be an articulating rudder. If you google this you'll read all sorts of things about increased control at lower speeds, but they are very expensive but none the less an option to ask about.

Jim F

 

[abcandjrc]

Actually, the primary reason for thrusters is that something called "boat handling" is not a prime consideration to the majority of boat owners. Come on now, how many boats should really have flowers and candles on the table? We (a collective term) have put our emphasis on the wrong things when staying-alive-on-the-water actually depends on skills, not decor.

Technology is fine but not at the cost of disaster when it fails. I have the same problem with those who rely on their GPS and never learn how to read a chart, plot a course, and follow it by dead reckoning. Too much work, and of the worst kind.... thinking. Every failure we had with GPS (and I admit this was a few years back and the equipment is better by far now) was in a critical situation. We survived all of them.

Heck, I even have people look at me like I am nuts when I say "saloon". A few have even tried to argue the point. They have been fed "salon" by boat builders and magazines for years. Made it easier to convince the wife we guys need a boat if it had a salon instead of a saloon.

 

[Levitation]

You really have to stop reading Chapman's and the ilk or next you will be telling us that is is Larboard and not Port...
But excuse me for now as I have to go abaft the beam the check the baggywrinkles, polish the brightworks, and holystone the deck...

 

[abcandjrc]

To each his own, but I always use starch when I iron my baggies so they do not wrinkle.... But I sand and varnish my brightwork. Polishing should be reserved for the silverware. Check Chapman's........ or maybe even Conrad.

 

[baz]

I agree with jroyle that to take on a rudder modification on your own is not the best idea, unless you are a naval architect. With that said, if one is interested in making improvements, I'd suggest talking with Ranger Tugs directly to ask if they'd have a recommendation for a larger rudder to help at slow speeds. The disadvantage, as spelled out earlier, is a larger rudder increases steering sensitivity at higher speeds and therefore can be dangerous with to large a rudder.....therefore the reason for talking with Ranger Tug. Another option to get their opinion on would be an articulating rudder. If you google this you'll read all sorts of things about increased control at lower speeds, but they are very expensive but none the less an option to ask about.

Jim F

Jim: I do believe my dock buddy did contact Andrew about his rudder mod. I had asked him if he had and he replied that Andrew had no comment... that said it all for me. :!: I had concerns how the rudder mod would affect the Auto Pilot that he has installed on his boat as I know the Auto Pilot can cause sudden turns getting back on course after making a manual course deviation. I will be speaking to this dock buddy at the earliest opportunity and will pass along the thoughts expressed here in this thread. My dock buddy is not a spring chicken and now I'm quite concerned for him. He obviously went to some effort hauling the boat out to make the rudder mod. My goal will be to make him reconsider.

I thought a post here would clear the air on this issue... and it has done so for me.