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10-06-2021, 02:54 PM
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#1
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Member
City: Punta Gorda
Vessel Name: Uriel Fremont
Vessel Model: Mainship 34 Trawler
Join Date: Aug 2013
Posts: 9
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Prop Walk
I have a new to me 2005 Mainship 34 Trawler and would like to practice prop walk maneuvers without relying on the bow thruster. Q: Is my prop left-handed or right-handed? Also, is there much noticeable prop walk with these vessels? Thanks.
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10-06-2021, 03:14 PM
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#2
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Guru
Join Date: Jun 2008
Posts: 5,034
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Put it in reverse and you'll know which way the stern will walk in reverse.
You can do this tied in your slip/berth or out in more open water.
Try at idle first.
Then give it a little power and you'll be amazed at how you can control the walk and use it to your advantage.
It's easier than you think.
Have fun.
__________________
Jay Leonard
Ex boats: 1983 40 Albin trunk cabin, 1978 Mainship 34 Model 1
New Port Richey, Fl
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10-06-2021, 03:47 PM
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#3
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Guru
City: Cape May, NJ
Vessel Name: Irish Lady
Vessel Model: Monk 36
Join Date: Dec 2007
Posts: 4,947
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Just look at the shaft inside the boat and have someone bump it into FORWARD then back to neutral. If the shaft turns clockwise when viewed from the stern, it’s right handed rotation. Opposite equals left handed.
__________________
Archie
Irish Lady
1984 Monk 36 Hull #46
Currently in Cape May, NJ
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10-06-2021, 03:51 PM
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#4
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Guru
City: Gig Harbor
Vessel Name: Kinship
Vessel Model: North Pacific 43
Join Date: May 2015
Posts: 9,046
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As was mentioned, if your boat has noticeable prop walk, you should be able to tell as soon as you put the boat in gear. My boat’s stern definitely moves to port in reverse. Center your helm and put it in reverse and see if your boat starts to back to port or starboard. If it does neither, then you don’t have enough prop walk to worry about or use.
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10-06-2021, 08:00 PM
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#5
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Guru
City: Southport, FL near Panama City
Vessel Name: FROLIC
Vessel Model: Mainship 30 Pilot II since 2015. GB-42 1986-2015. Former Unlimited Tonnage Master
Join Date: Oct 2007
Posts: 4,977
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The single engine 34 will be right handed but the tunnel will negate just about any prop walk.
__________________
Rich Gano
FROLIC (2005 MainShip 30 Pilot II)
Panama City area
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10-06-2021, 10:55 PM
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#6
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Member
City: Punta Gorda
Vessel Name: Uriel Fremont
Vessel Model: Mainship 34 Trawler
Join Date: Aug 2013
Posts: 9
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Quote:
Originally Posted by rgano
The single engine 34 will be right handed but the tunnel will negate just about any prop walk.
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Thank you. What does the "tunnel" refer to?
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10-06-2021, 11:38 PM
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#7
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Moderator Emeritus
City: Au Gres, MI
Vessel Name: Black Dog
Vessel Model: Formula 41PC
Join Date: Jul 2015
Posts: 21,131
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The prop tunnel. The prop is partially recessed into the hull. Just give it a try and see what it does. Give it a burst in reverse with the rudder straight and see if it goes to port or starboard or neither. Just don’t do it near the dock until you get a feel for it.
__________________
Boat Nut:
If you are one there is no explanation necessary.
If you aren’t one, there is no explanation possible.
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10-07-2021, 02:50 AM
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#8
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Guru
City: Saint Petersburg
Vessel Name: Weebles
Vessel Model: 1970 Willard 36 Trawler
Join Date: Mar 2019
Posts: 7,167
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Prop walk will be most noticible when the boat is moving forward slowly and gear in reverse. As the vessel comes to a stop, the prop will bite and move the stern. A light 2-3 second "burp" of RPM (200 added rpm or so) as the boat slows will often exacerbate rhe prop walk.
Two exercises to practice are back and fill - used to make a u-turn in a fairway. Series of forward and reverse thrusts with helm hard over. Maintaining rotation momentum is what you're looking for.
Second is coming into a side tie such as a fuel dock. Find an open side tie and a calm day to practice. Pick a point on the dock where you want your bow to end up (usually a cleat) and aim behind that point 1/4 boat length. Approach that point at a 30-45 degree angle at slow speed - idle forward, maybe in/out of forward/neutral to keep speed down. When you're 1 boat length away from dock, put helm hard over and put gear in reverse, and use reverse thrust to modulate speed. Goal is for boat to glide sideways and gently press on its fenders as it comes to a stop.
Not everything is possible with a single and no thruster. Discretion is the better part of Valor.
Good luck
Peter
__________________
_______________________________________
Cruising our 1970 Willard 36 trawler from California to Florida
Join our Instagram page @MVWeebles to follow along
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10-16-2021, 04:11 PM
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#9
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Senior Member
City: Watts Bar Lake, Tn River
Vessel Name: RedBoat
Vessel Model: MS 34T
Join Date: Apr 2013
Posts: 148
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My 34T single (with the prop in a half-tunnel) has no noticeable prop walk in reverse. In forward at idle, it will turn to port slightly more sharply than to starboard, but I don't know if that has any relevance to prop rotation.
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LongJohn
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10-16-2021, 04:40 PM
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#10
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Guru
City: Stratford, CT
Vessel Name: Blue Moon
Vessel Model: Mainship Pilot 355
Join Date: Jan 2019
Posts: 3,937
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Sorry, but I have tried and think prop walk is overated. (Granted I also have a prop tunnel so maybe it's differnt for others) Yes it exists and yes you can make a u turn if the conditions are right. But fighting a strong current and/or wind, better to rely on trusters. It's helpful to know and learn about prop walk, but it's not the best solution in all situations. If it's you only solution, you better not navigate in challenging conditions.
Cargo ships rely on thrusters called tug boats.
__________________
“In my walks, every man I meet is my superior in some way, and in that I learn from him.” ― Ralph Waldo Emerson
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10-16-2021, 07:39 PM
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#11
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Master and Commander
City: Vallejo CA
Vessel Name: Carquinez Coot
Vessel Model: penultimate Seahorse Marine Coot hull #6
Join Date: Sep 2010
Posts: 12,559
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while making use of propwalk, much prefer using bow thruster rather than forwarding/reversing drive train to turn around to avoid overworking transmission and shaft.
__________________
Kar-KEEN-ez Koot
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10-16-2021, 07:40 PM
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#12
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Master and Commander
City: Vallejo CA
Vessel Name: Carquinez Coot
Vessel Model: penultimate Seahorse Marine Coot hull #6
Join Date: Sep 2010
Posts: 12,559
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Quote:
Originally Posted by backinblue
....
Cargo ships rely on thrusters called tug boats.
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Cruise ships rely on thrusters.
__________________
Kar-KEEN-ez Koot
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10-17-2021, 09:12 AM
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#13
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Guru
City: Newport, R.I.
Vessel Name: Hippocampus
Vessel Model: Nordic Tug 42
Join Date: Jul 2020
Posts: 3,871
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Practicing slow speed maneuvering with our new to us Nordic Tug 42. Totally different than a sailboat with a high aspect fin keel. Doesn’t pivot on the keel.Have found with a SD hull and nearly no shaft angle back and fill is just about the same to port or starboard. Found you really need a very brief burst of rpms and water flow across the rudder to get it to turn. Very unlike a high aspect balanced large spade rudder on a sailboat. So learning to give a very brief burst of throttle and right back to neutral. Prop walk is negligible. Other than sportfish with exposed running gear or non saildrive sailboats have come to think there isn’t enough prop walk on most recreational power craft to be very helpful or a major concern.
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10-17-2021, 09:15 AM
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#14
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Guru
City: Newport, R.I.
Vessel Name: Hippocampus
Vessel Model: Nordic Tug 42
Join Date: Jul 2020
Posts: 3,871
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Prop systems on many large vessels alias. Tug use is disappearing.
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10-17-2021, 09:33 AM
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#15
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Guru
City: Coupeville Wa.
Vessel Name: Pacific Myst
Vessel Model: West Bay 4500
Join Date: Oct 2015
Posts: 2,402
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Quote:
Originally Posted by Hippocampus
Practicing slow speed maneuvering with our new to us Nordic Tug 42. Totally different than a sailboat with a high aspect fin keel. Doesn’t pivot on the keel.Have found with a SD hull and nearly no shaft angle back and fill is just about the same to port or starboard. Found you really need a very brief burst of rpms and water flow across the rudder to get it to turn. Very unlike a high aspect balanced large spade rudder on a sailboat. So learning to give a very brief burst of throttle and right back to neutral. Prop walk is negligible. Other than sportfish with exposed running gear or non saildrive sailboats have come to think there isn’t enough prop walk on most recreational power craft to be very helpful or a major concern.
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The effect of prop walk is very boat dependent. With some boats it is pronounced enough that you can use it to advantage or if you aren't aware of it it can bite you in close quarters. I think it better to simply keep prop walk in mind. Most boats will turn in a tigherer radius one way than the other when backing and filling.
Do learn you boat's pivot point. Often but not always 1/3 the water line from the bow. Do learn your boat's turning radius at various engine speeds.
Regarding the need for water flow over the rudder. Yes, that is very important. One way to take advantage of that is to have a bit of stern way on then swing the rudder over and give the short burst of ahead. You can leave it in ahead longer while the boat stops the stern way while turning at the same time.
I have found with a lot of boats windage is a key factor to learn to handle and even use to your advantage. Many boats when backing the bow will fall down wind. With enough room or clever backing and filling you can end up stern into the wind. This can be very useful in the right situations.
Don't fight the boat or wind. If backing out into the fair way or turning the "wrong" way favors the boat and conditions then use it.
__________________
Some things are worth doing simply because they are worth doing.
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10-17-2021, 10:02 AM
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#16
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Guru
City: Rochester, NY
Vessel Name: Hour Glass
Vessel Model: Chris Craft 381 Catalina
Join Date: Aug 2019
Posts: 7,539
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Quote:
Originally Posted by Portage_Bay
The effect of prop walk is very boat dependent. With some boats it is pronounced enough that you can use it to advantage or if you aren't aware of it it can bite you in close quarters. I think it better to simply keep prop walk in mind. Most boats will turn in a tigherer radius one way than the other when backing and filling.
Do learn you boat's pivot point. Often but not always 1/3 the water line from the bow. Do learn your boat's turning radius at various engine speeds.
Regarding the need for water flow over the rudder. Yes, that is very important. One way to take advantage of that is to have a bit of stern way on then swing the rudder over and give the short burst of ahead. You can leave it in ahead longer while the boat stops the stern way while turning at the same time.
I have found with a lot of boats windage is a key factor to learn to handle and even use to your advantage. Many boats when backing the bow will fall down wind. With enough room or clever backing and filling you can end up stern into the wind. This can be very useful in the right situations.
Don't fight the boat or wind. If backing out into the fair way or turning the "wrong" way favors the boat and conditions then use it.
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Agreed. The pivot point is often further forward on inboard powerboats compared to sail. To some extent, you almost place the bow and maneuver the stern around it.
Amount of prop walk varies widely depending on the boat and prop in question. And you'll usually feel it more when you engage the gear that's opposite of the direction you're moving. Put the boat in reverse while moving forward and you may have enough prop walk to start a turn as you stop. But backing from a stop may not give much.
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10-17-2021, 10:20 AM
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#17
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Guru
City: Newport, R.I.
Vessel Name: Hippocampus
Vessel Model: Nordic Tug 42
Join Date: Jul 2020
Posts: 3,871
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Thanks guys. Have a lot of relearning to do. Finding my brain is used to 35 years of sail and it just gets in the way. Unlearning is harder than learning so frustrating right now. I’m a total newbie. Find the remoteness of electric helm and hydraulics hard as well. No feel. Totally dependent on your eyes and instruments to know what’s going on.
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10-17-2021, 10:24 AM
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#18
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Guru
City: Rochester, NY
Vessel Name: Hour Glass
Vessel Model: Chris Craft 381 Catalina
Join Date: Aug 2019
Posts: 7,539
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Quote:
Originally Posted by Hippocampus
Thanks guys. Have a lot of relearning to do. Finding my brain is used to 35 years of sail and it just gets in the way. Unlearning is harder than learning so frustrating right now. I’m a total newbie. Find the remoteness of electric helm and hydraulics hard as well. No feel. Totally dependent on your eyes and instruments to know what’s going on.
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After a while you start to get a gut feel for now much steering input to give with the hydraulics. Even with no rudder position indicator. The upside is that if you need your hands for other stuff, you can take your hand off the wheel and know that the rudder will stay right where you left it.
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10-17-2021, 10:50 AM
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#19
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TF Site Team
City: Saltspring Island
Vessel Name: Retreat
Vessel Model: C&L 44
Join Date: Nov 2007
Posts: 5,656
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Quote:
Originally Posted by Hippocampus
Totally dependent on your eyes and instruments to know what’s going on.
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Watching the effect of any change in gear, throttle or direction is the critical piece. Seems you have already figured this out.
Once you know what to expect, in your own circumstances, of any addition or subtraction of thrust, change in direction of thrust, will lead to immediate predictability and reliability.
Much more eyes than instruments, though without rudder feedback, you need a rudder indicator. Hearing can replace tachometers, gear lever position is sometimes needed, always available by feel rather than eyes. You can maintain a constant watch (eyes only use) for the movement of your boat relative to the docks, boats, shorelines, while knowing what the engines and rudders are doing from other cues that are available to hands and ears.
__________________
Keith
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10-17-2021, 11:52 AM
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#20
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Guru
City: Aventura FL
Vessel Name: Kinja
Vessel Model: American Tug 34 #116 2008
Join Date: Oct 2017
Posts: 10,595
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Quote:
Originally Posted by rgano
The single engine 34 will be right handed but the tunnel will negate just about any prop walk.
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On my AT, I park bow in. When I wish to depart, I swing the rudder about 30 degrees to port, at idle, it will back straight.
Of course, that degrees to port may have to 'modified' depending on wind and current.
Practice a bit and you will not only surprise yourself but also impress the "observers".
One further point, you should center the hyd stabilizers before backing up.
__________________
Two days out the hospital after a week in the hospital because of a significant heart attack.
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