Ooops seem to have ended up in the Sunseeker sales office....

[Pinnacle]

That was September 2015. We had the pleasure of being there at the beginning of that month.

MapisM and his SWMBO are fab hosts and the cruising is spectacular. :encouragement:

 

[scubaman]

.

MapisM and his SWMBO are fab hosts and the cruising is spectacular. :encouragement:

+100 to that. Wonderful memories to cherish amid the darkest part of the year.

 

[TwoHooter]

Well, that depends on how well the boat is anchored.

Classic Godwin touch-and-go

 

[Forty_Two]

Before you commit, do speak to a marine insurance company as I have a friend who had little boating experience & they insisted on a skipper on all outings. That was a SS 56. Boat next to us two years ago had the same. Could affect your choice.

 

[westernman]

Before you commit, do speak to a marine insurance company as I have a friend who had little boating experience & they insisted on a skipper on all outings. That was a SS 56. Boat next to us two years ago had the same. Could affect your choice.

A good reason to get some kind of qualification e.g. RYA Coastal Skipper (or whatever it is called these days).

 

[westernman]

I am surprised nobody has commented on the IPS drives. These seem to be very vulnerable, prone to damage and a source of big bills down the road.

If you run across a fishing net in the water, you have no protect at all and you risk wiping out both drives at the same time.

Surely a shaft drive protected by a keel in front is much better? And with a nice big rudder behind the prop, the maneuverability using the prop wash over the rudder is very good as well.

 

[Nick_H]

I am surprised nobody has commented on the IPS drives. These seem to be very vulnerable, prone to damage and a source of big bills down the road.

If you run across a fishing net in the water, you have no protect at all and you risk wiping out both drives at the same time.

Surely a shaft drive protected by a keel in front is much better? And with a nice big rudder behind the prop, the maneuverability using the prop wash over the rudder is very good as well.

A few people have commented on IPS drives, advising against them. I'm also not keen for the reasons you state, but to be fair they've been around quite a while now and the internet doesn't seem to be full of horror stories of failing IPS systems or huge repair bills, and the few people on here who have IPS boats seem happy with them. I still don't think the benefits outweigh the potential risks or extra service costs though.

A shaft drive boat like the SS52 that Greenhorn is considering does not have the keel protecting the props, so they are just as likely to be fouled or damaged. In fact the IPS system is designed to shear on impact and protect the boat from flooding, so it may be safer than shafts, although there are some cases where this doesn't seem to have happened, possibly down to the hull around the drives not being sufficiently reinforced.

I'm struggling to see how a single prop, even with a big rudder, is more manoeuvrable that twins, be that IPS or shafts.

 

[MapisM]

@ Pinnacle+Scubaman: many thanks folks for your kind words, and also for coming. It has been a pleasure indeed, for both myself and S. :encouragement:

 

[MapisM]

I'm struggling to see how a single prop, even with a big rudder, is more manoeuvrable that twins, be that IPS or shafts.

I'm not sure that's what MC suggested - and if he did, he was wrong, particularly in reverse.
That said, I've seen fishermen maneuvering 30m steel vessels with a single screw and no thrusters in a way that would put our concerns to shame...
At the end of the day, it's all down to practice, practice, practice.

 

[Nick_H]

I'm not sure that's what MC suggested

Yep, reading it again he probably didn't say that, just that a single shaft can still have good manoeuvrability, which is true of course. Note to self -RTFQ!

 

[Whitelighter]

I am surprised nobody has commented on the IPS drives. These seem to be very vulnerable, prone to damage and a source of big bills down the road.

If you run across a fishing net in the water, you have no protect at all and you risk wiping out both drives at the same time.

Surely a shaft drive protected by a keel in front is much better? And with a nice big rudder behind the prop, the maneuverability using the prop wash over the rudder is very good as well.

Few motoboats have a keel in front of the props or big rudders behind.

Any rudder use at slow speed is futile - low speed steering is by means of either prop walk or opposing the engines

 

[MapisM]

Any rudder use at slow speed is futile

You never helmed a sailboat J, did you?
Actually, also on a mobo, it's just a matter of size.
But due to the hull shape and the displacement/length ratio, the rudders should be ridiculously large to be effective at slow speed.
And particularly with twin engines and P boats, that wouldn't make any sense.

 

[Whitelighter]

You never helmed a sailboat J, did you?
Actually, also on a mobo, it's just a matter of size.
But due to the hull shape and the displacement/length ratio, the rudders should be ridiculously large to be effective at slow speed.
And particularly with twin engines and P boats, that wouldn't make any sense.

Actually I have - maybe 5000 miles over my lifetime.
And in understand on a sailboat exactly how it works but that is not relevant in the discussion about ips over shafts.

The op is looking at a fast planing motorboat - tell me such a boat that has keel(s) in front of the props or a large rudder.

I also have experience with an Elling E3 - single shaft with a largish rudder and while it has more effect at slow speed the prop walk was more

 

[MapisM]

All agreed - I just read your statement as meant to generalize...

 

[westernman]

Few motoboats have a keel in front of the props or big rudders behind.

Any rudder use at slow speed is futile - low speed steering is by means of either prop walk or opposing the engines

Ok I don't have a mobo, but I can assure you that low speed steering is by using prop wash over the rudder. At 0.0kts I can position the stern of my boat with millimetre accuracy when reversing into a tight spot. No need to be moving to have steerage.

(Can't do much about the bow though). I am 67ft LOA, single shaft drive, no bow thruster and enough windage to put a block of flats to shame.... Now that I have changed the feathering prop for a real fixed propeller, maneuvering has become a whole lot easier.

 

[westernman]

Few motoboats have a keel in front of the props or big rudders behind.

This one has both. (Nicked of the Nordhavn thread):-

I suspect that many single prop boats with shafts have this configuration.

 

[Canopy Locked]

Another rudder style.. just for interests sake.

Can't say it was any better / worse than a traditional rudder

 

[Whitelighter]

This one has both. (Nicked of the Nordhavn thread):-

I suspect that many single prop boats with shafts have this configuration.

Yes, and I did say 'few' - meaning there are of course some.

However, the OP is (or at least was) looking at planing motorboats and the discussion against IPS is versus shafts in that configuration.

On that type of boat, which is what we are discussing, there is no keel and tiny rudders. Even on many single engine shaft drive boats there is no keel (though a few have a skeg) and then the rudder is bigger but with 400-600 Hp going through a single shaft overcoming prop walk is not easy, even with a big rudder.

 

[Whitelighter]

Ok I don't have a mobo, but I can assure you that low speed steering is by using prop wash over the rudder. At 0.0kts I can position the stern of my boat with millimetre accuracy when reversing into a tight spot. No need to be moving to have steerage.

(Can't do much about the bow though). I am 67ft LOA, single shaft drive, no bow thruster and enough windage to put a block of flats to shame.... Now that I have changed the feathering prop for a real fixed propeller, maneuvering has become a whole lot easier.

Yes, but your boat is a world away from a planing motorboat which is very very small rudders and much less boat in the water.

You are comparing apples with, well not even oranges, more like spaghetti

 

[benjenbav]

Yes, but your boat is a world away from a planing motorboat which is very very small rudders and much less boat in the water.

You are comparing apples with, well not even oranges, more like spaghetti

Here's a picture of the sterngear of my last boat, with rudders behind the props and a keel to protect.

Semi-D, not fast planing, though.