Sail to power "conversion" training / familiarisation

Scala said:
I guess that must be right. IPS also. But presumably a shaft drive with rudders is more steerable,,,
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A shaft drive with rudders steering is only marginally better than outdrives (with way but no power)
The steering component is from the rearward thrust from the prop hitting the rudder and being deflected.
To me the steering for close quarter manoeuvring is better with shafts as the drive is closer to the boat pivot point.
 
My boat is a deep vee with twin shafts, it steers quite well at low speed in neutral, the rudders hang below the hull. It handles quite differently to the smaller outboard rib I did pb2 on.
I would think pb2 would be a fun course for you to do, if nothing else you would get used to travelling several times faster than a sailing boat!
 
Elessar said:
I’ve taught quite a few sail to power people and getting yotties to slow down is the challenge!

For the reasons you say they are used to going fast enough for the rudder to bite, which in my boat is about 6 knots. About 5.5 knots too fast!
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That was certainly my experience. It feels completely unnatural to be creeping about in a large motorboat.

I did find it helpful to think of the steering wheel turning a thruster rather than a rudder and having a mental picture of which way it's pointing. For example, wheel hard over the port, the props are pointing starboard. Go astern with the engine on the outside of the turn, i.e. starboard and the stern will be dragged round to port. (I think!). Then remember to centre the wheel again to avoid unexpected changes of direction next time you touch the throttles.

The point is that a motorboat (sterndrive in particular) requires a different way of thinking about maneuvering. Eventually, I guess it becomes second nature, but it's a steep learning curve!
 
Yes, I think that's right. Intellectually I can visualise what's happening (or going to happen) but getting an intuitve feel for it will take time.

Forumite Elessar has very kindly offered us a day out on his boat for a bit of a play and practice. Costs covered of course, but I think it's a very generous and kind hearted offer.
 
K
SimonD said:
That was certainly my experience. It feels completely unnatural to be creeping about in a large motorboat.

I did find it helpful to think of the steering wheel turning a thruster rather than a rudder and having a mental picture of which way it's pointing. For example, wheel hard over the port, the props are pointing starboard. Go astern with the engine on the outside of the turn, i.e. starboard and the stern will be dragged round to port. (I think!). Then remember to centre the wheel again to avoid unexpected changes of direction next time you touch the throttles.

The point is that a motorboat (sterndrive in particular) requires a different way of thinking about maneuvering. Eventually, I guess it becomes second nature, but it's a steep learning curve!
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Er Port?
 
You may be right but I would have volunteered the same correction as @Rocksteadee. To save confusion, it's simpler (in my mind at least) to imagine and describe the direction that the drive / leg is pointing. Turn the when to port and the outdrive(s) point to port. Apply reverse thrust to the outer drive (the starboard one) and the stern is pulled to port. Apply forward thrust to the same outer drive and the stern is pushed to starboard.

The interesting think is understanding what this does to the bow as the pivot point is usually just slightly forward of the engines. That's why a dab of sternthruster allows you to effectively move the boat sideways.
 
Scala said:
I think he means that with teh wheel hard to port (ie, with the intent to steer the boat to port) a line drawn through the centreline of the prop runs forwards toward the starboard bow.
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Thanks Graham. That is indeed what I meant. Whichever way you describe it, just have the mental picture in mind (I have a plan view in mine). Using the engine on the opposite side of the turn gives maximum leverage. I imagine that using the other one would do the same thing, but with lesser effect. I also found that, if you have morse controls, it's essential to have them operating freely. You need to be able to just click the engine into gear and straight back out. Mine was very stiff to start with (needed lubrication at the Dual Station end) which made life very difficult, even for the instructor!
 
SimonD said:
Thanks Graham. That is indeed what I meant. Whichever way you describe it, just have the mental picture in mind (I have a plan view in mine). Using the engine on the opposite side of the turn gives maximum leverage. I imagine that using the other one would do the same thing, but with lesser effect. I also found that, if you have morse controls, it's essential to have them operating freely. You need to be able to just click the engine into gear and straight back out. Mine was very stiff to start with (needed lubrication at the Dual Station end) which made life very difficult, even for the instructor!
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You’re right.
If you have a sterndrive boat, go into a marina fairway - turn round and come back out.
Using exclusively the “correct” (outer) engine you will spin on the spot and be out in 3 wheel turns.
Do the same exclusively on the “wrong” engine and it will be a 9 point turn instead. If there’s a breeze you may not even make the turn.

There are times to use the “wrong” engine. Eg if portside to a pontoon, with a little bit of port helm, and the port engine forward, the boat will move forward and stay parallel to but move away from the pontoon. When you are used to your boat you can get the right amount of helm to crab like that to great effect.
Can’t do that in a shaft drive you have to pivot off your fenders or (heaven forbid) blip your bowthruster to gain clearance from the pontoon.
 
Elessar said:
You’re right.
There are times to use the “wrong” engine. Eg if portside to a pontoon, with a little bit of port helm, and the port engine forward, the boat will move forward and stay parallel to but move away from the pontoon. When you are used to your boat you can get the right amount of helm to crab like that to great effect.
Can’t do that in a shaft drive you have to pivot off your fenders or (heaven forbid) blip your bowthruster to gain clearance from the pontoon.
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May I beg to differ? We were shown by an experienced boat handler on the Thames last year that, to move away from a stationary position alongside in a lock, just put the helm a bit to Port and just click into ahead on the Port engine. The prop wash tries to kick the stern to Starboard and the turning effect from the Port prop tries to turn the bow to Starboard also, result a gentle movement away from the wall. You do have to centre the helm quickly and engage the other engine. We found it excellent advice and have used it ever since in that situation. This with shaft drives and no thrusters. Would not work very well in an onshore breeze though.
 
Leighb said:
May I beg to differ? We were shown by an experienced boat handler on the Thames last year that, to move away from a stationary position alongside in a lock, just put the helm a bit to Port and just click into ahead on the Port engine. The prop wash tries to kick the stern to Starboard and the turning effect from the Port prop tries to turn the bow to Starboard also, result a gentle movement away from the wall. You do have to centre the helm quickly and engage the other engine. We found it excellent advice and have used it ever since in that situation. This with shaft drives and no thrusters. Would not work very well in an onshore breeze though.
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Yep it can work if you have big rudders. It doesn’t work on mine so that’s my defence but you are right. (Of course because you do it!!)

I’d add though it’s easier in a stern drive as you don’t have to recentre the wheel when you take the power off. (Too much defence for being wrong??)
 
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Originally Posted by Elessar
image: http://www.ybw.com/forums/images/ybw/buttons/viewpost-right.png
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You’re right.
There are times to use the “wrong” engine. Eg if portside to a pontoon, with a little bit of port helm, and the port engine forward, the boat will move forward and stay parallel to but move away from the pontoon. When you are used to your boat you can get the right amount of helm to crab like that to great effect.
Can’t do that in a shaft drive you have to pivot off your fenders or (heaven forbid) blip your bowthruster to gain clearance from the pontoon.

Read more at http://www.ybw.com/forums/showthrea...ing-familiarisation/page6#JApQ8zuUQSXgveBw.99

Leighb said:
May I beg to differ? We were shown by an experienced boat handler on the Thames last year that, to move away from a stationary position alongside in a lock, just put the helm a bit to Port and just click into ahead on the Port engine. The prop wash tries to kick the stern to Starboard and the turning effect from the Port prop tries to turn the bow to Starboard also, result a gentle movement away from the wall. You do have to centre the helm quickly and engage the other engine. We found it excellent advice and have used it ever since in that situation. This with shaft drives and no thrusters. Would not work very well in an onshore breeze though.
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Different words, same description.
Also works on twin shaft drive
 
Rocksteadee said:
Originally Posted by Elessar
image: http://www.ybw.com/forums/images/ybw/buttons/viewpost-right.png
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You’re right.
There are times to use the “wrong” engine. Eg if portside to a pontoon, with a little bit of port helm, and the port engine forward, the boat will move forward and stay parallel to but move away from the pontoon. When you are used to your boat you can get the right amount of helm to crab like that to great effect.
Can’t do that in a shaft drive you have to pivot off your fenders or (heaven forbid) blip your bowthruster to gain clearance from the pontoon.

Read more at http://www.ybw.com/forums/showthrea...ing-familiarisation/page6#JApQ8zuUQSXgveBw.99



Different words, same description.
Also works on twin shaft drive
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Yes I know don’t rub it in. I’ve admitted I was wrong to say it doesn’t work on shafts. I still maintain it’s easier on outdrives and used the excuse that it doesn’t work on my shaft drive boat.
But now I’m doubting myself. I’m going to have a play tomorrow. I will admit it if I was wrong about that too.
 
Elessar said:
Yes I know don’t rub it in. I’ve admitted I was wrong to say it doesn’t work on shafts. I still maintain it’s easier on outdrives and used the excuse that it doesn’t work on my shaft drive boat.
But now I’m doubting myself. I’m going to have a play tomorrow. I will admit it if I was wrong about that too.
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Wasn’t rubbing it in. I had missed your previous post.
Have a play and see what it does
On mine with small rudders but big props, the drive forward has more effect than the crab sideways when on full helm.
Another little trick is to crab sideways is full helm and alternate very small CW and ACW rotations. This is a fairly slow process so the slightest wind or tide pushing back on and it won’t work.
 
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Rocksteadee said:
Wasn’t rubbing it in. I had missed your previous post.
Have a play and see what it does
On mine with small rudders but big props, the drive forward has more effect than the crab sideways when on full helm.
Another little trick is to crab sideways is full helm and alternate very small CW and ACW rotations. This is a fairly slow process so the slightest wind or tide pushing back on and it won’t work.
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Too breezy and too many people on board today so I didn’t experiment. I pivoted around my ball fender to get off my blown on berth. And so nothing to report. ......,
 
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