Right-hand versus left-hand propellers

[markpierce]

For single-engined boats, I was under the impression that right-hand propellers are far more common than left-hand ones. The Coot has a left-hand propeller. This raised some questions.

1. Which of you have left-hand versus right-hand propellers?
2. Is it an advantage to have a starboard-side helm versus a port-side helm with a left-hand propeller?
3. With a left-hand propeller, what is the preferred dock orientation in relation to the dominant wind/current?
4. With a keel at the stern and large rudder, is prop-walk even a significant issue?

 

[Moonstruck]

Mark, most boats either have center steering or starboard side steering because the danger zone in a crossing situation is more readily viewed.* Your boat looks as if it has starboard side steering with a door at hand.* This is a great set up.* What you want is a propellor that will cause the boat to back to starboard with the prop torque.* That way you can head into the dock at a slight angle, then put it in reverse to snug the stern to the dock.* A left hand prop accomplishes this, and I believe that most trawler yachts come with a left hand wheel.* I know mine did.

 

[awpptdt]

* My Marine Trader 40' sedan has a left hand prop. I believe all Marine Trader single engine trawlers have left hand Props. As mentioned above I like the prop walk when docking. As for forward motion I have never noticed any prop walk.

 

[jleonard]

My Albin has a Right hand prop. And I thought most had a Right hand until I read what Moonstruck wrote so who knows??

I know most of the old original Mainship Nantucket style boats*were RH. All the Duffy's I've been in were RH.

My old Mainship had significant prop walk. It was high impossible to back straight unless you has some serious speed going, more than would be comfortable. I had no issue once I learned the boat. You can use prop walk to your advantage. I had a slip in the correct side of the dock for an RH prop, but the old master with a Duffy on the other side did just fine also. You just need to learn your boat and try not to force it to do something it can't do.

 

[Bendit]

Pioneer has a right-handed prop and both steering stations to port.

Despite a having deep full-length keel and a large rudder, in reverse, there is a lot of prop walk to port. So much so that, in calm conditions, I can stop just past the marina berth and reverse into it with a 90deg turn to port without using the bow thruster.

I always try to come along side a wharf to port so I can nudge in with the bow and kick the stern in with reverse. Getting off is easy with a nudge forward to kick the stern out and a simultaneous*burst of thruster to bring the bow out.

Having owned twin-engined sport fishers previously, I find the single-engine with bow-thruster*easier to*manage alone*in almost all conditions.

 

[Moonstruck]

Bendit wrote:
*I find the single-engine with bow-thruster*easier to*manage alone*in almost all conditions.

*Bendit, that has been my experience also.* A single with a bow truster is a piece of cake to handle.* I have owned three (still have one) single screw boats.* all were left hand props.

Moonstruck has twins and a bow thruster.* The bow thruster is hardly used.* It comes in handy for moving the bow over to lassoo a piling.

 

[Jay N]

LH prop here, but movement of the stern to strb when backing is very small.

With only a few exceptions,*commercial single screw vessels are RH.

 

[dwhatty]

Jay N wrote:
LH prop here, but movement of the stern to strb when backing is very small.

Same here. I frankly don't notice much movement to the side in backing. And the rudder is so small it has little influence.

 

[Codger2]

dwhatty wrote:Jay N wrote:
LH prop here, but movement of the stern to strb when backing is very small.

Same here. I frankly don't notice much movement to the side in backing. And the rudder is so small it has little influence.

*Me too!

 

[Anthonyd]

Jay N wrote:
LH prop here, but movement of the stern to strb when backing is very small.

With only a few exceptions,*commercial single screw vessels are RH.

*I guess I have a lot to learn. In the few years that I have worked on diesel engines, the ones I have worked on have all spun clockwise when facing the engine, or counter-clockwise when facing the bow. This holds true on my pick-up which has a Duramax, and my dad's Cummins. The few steamers I worked on also rotated this way and so do the engines on the trucks and tractors I have worked on in the past. Most of the ships I work on now are newer and are direct drive so no transmission. I guess my question is does the tranny change the direction of rotation of the shaft and prop? I have not owned a trawler yet, but my dad's boat with Crusaders has tranny's and the props spin in the same direction as the engine. I just started working on the smaller boats now that I am not sailing on commercial ships so much so I still have limited experience in this area. Sorry for changing topics but it was a little confusing to me and I like to have the right information.

 

[Nomad Willy]

Most engines you'll find in a trawler run counter clockwise (ccw). And the direction of rotation is always specified while viewing the flywheel from behind. There are two types of gear boxes. The one most common in old trawlers is a Brog Warner Velvet Drive. I'm quite sure the BW gear has a planetary arrangement of gears and hence the output shaft rotates with the engine*** ....ccw. The other type of gear is what I call a two shaft gear. The* upper shaft (input shaft) is connected to the flywheel/engine. The lower shaft is connected to the propeller shaft via gears rotating on the 2 shafts. As is obvious the gears on each shaft rotate in opposite directions so the propeller rotates the opposite direction of the engine ....cw.* Most modern gears are of this type. One of the advantages/disadvantages of each type of gear is that the 2 shaft gears have the output shaft several inches below the engine's crankshaft so if you want to switch from one type of gear to the other raising or lowering the engine will probably be necessary.

Most boats have the helm on the side of the boat whereas boats approaching from that side have the right-of-way*** ...see Chapman's. So stbd helms are the most common and most desirable. So when landing a boat w a LH prop it is more desirable to have the helm to stbd. My Willy has considerable prop walk and I prefer landing to stbd. But landing on the disadvantageous (relative to prop walk) side is not as difficult as one might think. Approach the float at a greater angle (more at right angles to) and approach as slow as possible. At just the right time throw the helm all the way over so as to turn as sharply as possible. Turning so as to miss the float but not by much the boat will swing it's stern toward the float smartly if you do this maneuver well. Inertia will swing the stern toward the float and overpower the prop walk. When you hit reverse w a smart blast of throttle (remember...there's not much response in reverse) the stern's swing toward the float will be arrested or minimized so a perfect or near perfect landing will result. Put a ton of fenders over the side practice. Then you may be able to amaze your friends w your skill.

 

[Woodsong]

My Monk has some serious prop walk to starboard!!! I have been getting used to it and never been an issue yet but it sure as heck plays a big role in deciding which slip I keep my boat in! I have really been toying with putting a thruster in this fall, assuming I haven't moved up to a 3 stateroom 50 footer by then.

 

[FF]

I think LH is the more common , stern walks to Stbd on reversing.

RH , stern walks to port on hitting reverse .

In the Canadian locks most of the nike boats were 30ish and most walked to stbd, so when we chose the port wall with a 50 ft , most were delighted , as it was not where they wanted to be.

With a light boat and 32X32 square prop the walking is very pronounced and useful.

A twin will have the props rotating in on each other.. viewed from aft.