How to turn a Traditional Motorsailer into a Sailing Boat

B27

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For brevity, I won't quote the post above.
Some good points.
But 'weather helm' is more complex.
Have a go in a Laser dinghy.
The rudder is terrible, mostly a brake.
Steer by hull form, sitting out and sheeting.

With a small yacht, a gust hits, it heels, how does that affect the steering.
A small factor of heeling causing the boat to luff and hence lose power may be beneficial, in the overall scheme,

Too much becomes 'rudder fights sails'.

With my boat, I'm learning that above x knots of true breeze, the right number of rolls in the jib gives a gust response of 'luff a bit and keep speed'. Get it wrong and we either luff a lot or lose speed due to needing a lot of rudder.
 

Laminar Flow

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I hardly think that a 12.5' Laser is comparable to a 6 or 8 ton cruiser, which can not likely be trimmed out in seconds. To be sure, a 10,000 lbs boat would need a 4 1/2 ton weight on a 10' lever to simulate the effect the crew has on that Laser.

Unfortunately, as beam increases, so does the probability that there is a significant shift in the longitudinal centre buoyancy as the boat heels and with this an increase in weatherhelm.

Narrow boats fair much better in this respect, as do double enders with balanced entry and exit lines.

However, the surest way to increase stability in a shallow draft boat is to make the boat wider. Stability increases to the cube of the beam. Alas, this will increase rudder loading (see second paragraph) and a shallow rudder is already at a disadvantage for the reasons mentioned in my previous post.

Best, A.
 

flaming

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Your addition of bow sprit - is what I thought of doing to my SR25 .... she also has terrible weather helm ... not only from the mainsail - but also that the CoE of the genny needs to go more fwd. Its a bit of a 'trick' on her .. when people helm her and say - blimey - weather helm .. I say OK - you're on the helm - what do you want to do .. they all say - reef the main .. so we do it ... BLIMEY there's still weather helm ..
That's when I chuckle and furl a bit of genny and viola - its reduced to slight.

vITb07Cl.jpg


I thought to add a second foresail .. save mucking about with the furler etc.
I'd be interested to know if dropping the car back a couple of holes had the same effect as reefing the genoa. And I'd expect it would....
 

flaming

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A few thoughts on weatherhelm:

Traditionally and when calculating a balanced sail plan, CLR was determined without the rudder entirely, or only by half. As a result you would find large, tiller steered vessels that could be managed with just two fingers. I have sailed on an Atkin's double-ender with an incredibly large gaff rig, that had an amazingly light helm.

With keels getting shorter by the minute and having become completely separate from the steering end of things, the rudder is now considered an essential part of lateral plane and the lift generating surfaces. Conversely the loading on the rudders has increased substantially.

Foils are sensitive (some profiles more than others) to turbulence in the water, particularly ones of a high aspect ratio and a short chord.
Things like blunt deadwoods, surface proximity and props create considerable turbulence. Indeed, a common observation by owners who converted to a folding or feathering prop is that it "miraculously" cured their weatherhelm issues.
Shallow draft boats are in this respect at a greater disadvantage, as the relationship between prop diametre and rudder depth is less favourable, as is the surface proximity on a shallower rudder.

Consequently, the business of sail balance is a much more sensitive issue, but that still becomes a challenge in conditions where effective rudder response is paramount and rudder loading is accordingly high.

Before we had made the modifications, the rudder would stall out at the slightest provocation and, with the rudder hard over, the boat would be carrying on in a straight line. Apart from the lack of steerage, the resistance caused by a rudder going sideways through the water would obviously be enormous.
All that changed the instance we made the modifications.
The optimum rudder angle for a beneficial lift/drag ratio is 2.5 degr. and this is where we are at now with a more carefully balanced sail plan and optimized steering end.

In regards to the general acceptance of wheelhouse concepts:
When the first Moody DS designs came out, essentially a deck level wheelhouse on a modern hull, I remember well the unqualified comments in the yachting press as to how much terrible windage this feature may cause on what clearly is a cruising boat. One does have to wonder how far removed from the reality of real world cruising some of these yachting reporters are. I have yet to see the performance deficit quantified in any real terms, to windward or otherwise and certainly not by comparison to a fully enclosed canvas cockpit enclosure on a standard AWB, with the molded freeboard of an aircraft carrier. I won't even mention the windage or the stability concerns of double-sided rows of jerry cans along the side decks, because the manufacturers chinzed out on the tankage necessary for real cruising.
Best, A.
Absolutely recognise the changing the prop removing the weather helm. Had exactly that on my Dad's old boat. Wouldn't have believed how much of an effect it had if I hadn't experienced it.

Obviously twin rudders are even better in this way, as they are not in line with the prop or keel, and also as the boat heels become deeper and more vertical in the water instead of shallower and less vertical.

I sailed the Moody 45 when it first launched. Marvellous boat, I liked it a lot, and it sailed pretty well.

However, for me sailing is an outdoor sport. Wheelhouse boats are interesting in a sort of "huh, that's nice" kind of way, but for the uplift you have to pay to get one you can buy a lot of very good foul weather kit....
 

rotrax

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Just an observation from a fairly new sailor at the time.

We had a Hunter 27 OOD, decent rig, bulb keel, deepish spade rudder.

When overpressed-as it was quite often in our early days-it was clear to me that the rudder became a bit of a foil as it moved nearer the surface when well heeled over.

This had the effect of pushing the bow down a bit, depending on the tiller position.

Might be total bolleaux, but I certainly had that impression.
 

Refueler

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I'd be interested to know if dropping the car back a couple of holes had the same effect as reefing the genoa. And I'd expect it would....

No way to get car back any further - its already at max aft ... the only way to change sheeting angle would be to run sheets back to the spinnaker sheaves - but they are way too aft.

What I find amazing is that Bristows Book of Yachts shows the SR25 with a huge sweeper of genny ...

3WCxkW2l.jpg


I definitely would not want to be on the tiller with that !!
 

flaming

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No way to get car back any further - its already at max aft ... the only way to change sheeting angle would be to run sheets back to the spinnaker sheaves - but they are way too aft.

What I find amazing is that Bristows Book of Yachts shows the SR25 with a huge sweeper of genny ...

3WCxkW2l.jpg


I definitely would not want to be on the tiller with that !!
Then I'd be looking at a change in shape when it's new sail time.
 

flaming

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Beat you to it !! Genny already replaced with a slightly shorter foot, longer luff .... which has made quite a diference ....

Basically minimal loss of sail area - but better sheeting angle and CoE has moved fwd.
But still no ability to drop the car back when you get weather helm?
 

Refueler

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But still no ability to drop the car back when you get weather helm?

The track extends as far back as it can on the side deck .. the car is all way back ... the only way to use the cars and get possibly better sheeting angle is to use a barber on them from the cars and sheets back to the spinnaker sheaves aft of the winches. But then - when I used - the sail wants to stay out from side of boat ....

Not being difficult or funny ... but I've had the boat nigh on 25yrs .. with all sorts of people sailed on her - many much better sail handlers than I ... we've all had a gander at it ...
 

flaming

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The track extends as far back as it can on the side deck .. the car is all way back ... the only way to use the cars and get possibly better sheeting angle is to use a barber on them from the cars and sheets back to the spinnaker sheaves aft of the winches. But then - when I used - the sail wants to stay out from side of boat ....

Not being difficult or funny ... but I've had the boat nigh on 25yrs .. with all sorts of people sailed on her - many much better sail handlers than I ... we've all had a gander at it ...
But if you changed the design of the sail so that in the "optimum" the car position was forward from where it is now, then you'd have track left over to drop it back when you needed to.
 

Refueler

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But if you changed the design of the sail so that in the "optimum" the car position was forward from where it is now, then you'd have track left over to drop it back when you needed to.

I've just bought a bigger boat that will occupy my mind on performance matters ... my older 25 will be mainly used on the river where its not going to be such a matter to spend time on ...
The new sail has improved her such that I no longer really think about it and the original idea of the bow sprit is just that - an idea now.

Here's the two together just before lift out.

mhspZwCl.jpg


The 25 is of course subject of keel repair after hitting submerged concrete block ... thread on this forum.

The 38 behind her has various work planned ..
 

dunedin

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................
We made the observation in the North (Scotland, Orkneys and Shetlands), that not only did we belong to the smallest boats that had made the trip, the average being at least 40' or more, but that almost all had, if not a pilothouse, a then a complete canvas cockpit enclosure. Additionally, most carried rows of jerry cans on deck.
I came away with the impression that the entire yachting industry appears to have missed the point when it comes to cruising yachts. Surprisingly, we saw none of those quick-footed light flyers, dashing through the Scottish rain.
Congratulations on the improvements made to your boat - looks like a massively more efficient rig than the original. Although perhaps personally, rather than adding a bowsprit I would have started with a longer hull - as there is no substitute for waterline length for relaxed mile munching.

And congratulations also for making it up to Orkney and Shetland - hope you enjoyed your cruise in these northern waters. When were you there ?

However, I find myself not recognising any of your observations about the types of boats sailing in Orkney and Shetland waters. We were there in May and June (covering from South Walls to Out Stack).
Perhaps the early season cruisers were more hardy than the later ones, but almost without exception the boats were standard cruising yachts (with aft or some centre cockpits) and of all sizes from 25 ft or so to over 60ft. I could literally name the handful of exceptions - one a pretty little Fisher Freeward (with deck saloon, not pilot house) and one a 60+ footer from New Zealand with a hard cockpit cuddy (I guess they have rough weather in the Southern Ocean).

In fact to check my memory I looked at my photos of Lerwick visitor pontoons (Shetland central, through which everybody passes) and they were entirely filled with the usual sorts of AWBs - Beneteau, Jeanneau, Moody, Westerly, Bavaria etc etc. Of the many boats rafted up, I could see just 2 enclosed cockpit tents and one deck saloon (on a large ketch) - out of 40 odd boats.
Most like us had a decent sprayhood. And I never once wished I had a pilot house or cockpit tent - and very rarely wore oilskins.

There were a very small proportion carrying jerry cans on deck. But not for visiting Orkney or Shetland, which have plenty of diesel available. Most of those that I spoke to were headed further North - to the Faroes and/or to the Lofoton Islands or beyond. Clearly these remote places did need a bit of self sufficiency.
One of these boats was a 32foot Beneteau that had left France in April (with a 1 month old baby) and had already been up the West side of Ireland and were en-route for the Faroes then Norway (they made it).
Of the boats I know which went to the Faroes all were standard modern aft cockpit AWBs, and none with a cockpit tent.

So I am not convinced that the yachting industry has gotten it so wrong. And no special boat types needed for cruising Scottish waters, or indeed further north.
If you want an example of what the Norwegians typically sail look at the video of the recent crossing from Norway to Shetland and back for Up Helly Ah.
 

Laminar Flow

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Congratulations on the improvements made to your boat - looks like a massively more efficient rig than the original. Although perhaps personally, rather than adding a bowsprit I would have started with a longer hull - as there is no substitute for waterline length for relaxed mile munching.

And congratulations also for making it up to Orkney and Shetland - hope you enjoyed your cruise in these northern waters. When were you there ?

However, I find myself not recognising any of your observations about the types of boats sailing in Orkney and Shetland waters. We were there in May and June (covering from South Walls to Out Stack).
Perhaps the early season cruisers were more hardy than the later ones, but almost without exception the boats were standard cruising yachts (with aft or some centre cockpits) and of all sizes from 25 ft or so to over 60ft. I could literally name the handful of exceptions - one a pretty little Fisher Freeward (with deck saloon, not pilot house) and one a 60+ footer from New Zealand with a hard cockpit cuddy (I guess they have rough weather in the Southern Ocean).

In fact to check my memory I looked at my photos of Lerwick visitor pontoons (Shetland central, through which everybody passes) and they were entirely filled with the usual sorts of AWBs - Beneteau, Jeanneau, Moody, Westerly, Bavaria etc etc. Of the many boats rafted up, I could see just 2 enclosed cockpit tents and one deck saloon (on a large ketch) - out of 40 odd boats.
Most like us had a decent sprayhood. And I never once wished I had a pilot house or cockpit tent - and very rarely wore oilskins.

There were a very small proportion carrying jerry cans on deck. But not for visiting Orkney or Shetland, which have plenty of diesel available. Most of those that I spoke to were headed further North - to the Faroes and/or to the Lofoton Islands or beyond. Clearly these remote places did need a bit of self sufficiency.
One of these boats was a 32foot Beneteau that had left France in April (with a 1 month old baby) and had already been up the West side of Ireland and were en-route for the Faroes then Norway (they made it).
Of the boats I know which went to the Faroes all were standard modern aft cockpit AWBs, and none with a cockpit tent.

So I am not convinced that the yachting industry has gotten it so wrong. And no special boat types needed for cruising Scottish waters, or indeed further north.
If you want an example of what the Norwegians typically sail look at the video of the recent crossing from Norway to Shetland and back for Up Helly Ah.

We were there during the Lerwick tall ship festival in August and again on the way back down. At 31.5' we were either the smallest or among the smallest boats. Most Boats were Norwegian, Dutch or German. The Brits were definitely in a minority. All the Norwegians had full canvas enclosures, the Dutch next to us had an enormous hard dodger and a canvas screen on their expedition style boat and there were a couple of Boreals. Yes, there were some AWBs, but none of them small or less than 35'. The prevailing image was foulies drying in the companionway. Most were on their way back from the Faroes or Iceland or on their way home to Norway.

Either way, we loved it and will be back. We are talking Norway next and back via the Shetlands again and the West coast of Ireland.

Our sprit is not to make the boat longer, but to increase sail area and improve sail balance.

On wheelhouses: I have sailed all varieties, and short of the Arctic, in all climate zones and offshore as well over long distances. I would never have anything else, but a pilothouse.
I do not have to stand at the helm, soaked to the bone by rain and spray, calling out to the storm: "I will not go gently into that good night".
I just slide the wheelhouse window open and without getting wet or catching a chill, do it from there.

Best, A.
 

Snowgoose-1

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Nice project with a very successful outcome. With four sails to manage, how did that go ?

Thread drift . Makes you wonder what it was like on the open bridges of RN Russian convoys.
 

Stemar

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I do not have to stand at the helm, soaked to the bone by rain and spray, calling out to the storm: "I will not go gently into that good night".
I just slide the wheelhouse window open and without getting wet or catching a chill, do it from there.
Absolutely. I've always thought that bashing back from Cherbourg in a rising 6, pouring rain and an open cockpit is an over-rated experience.

"Builds Moral Fibre" they used to say. Maybe I'm the wrong type of person but, in me, it builds a determination to get a better forecast next time
 

rotrax

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We have 3K's worth of boots, foulies, thermals, hats etc in a locker.

One set have been used three times in 7 years, both times for coming alongside or picking up a mooring in the pissing rain.

We had a very experienced yacht delivery crewman and fellow club member assist with our 500NM delivery trip when we bought her. He was very rude about our heavy, fat and poor sailing Island Packet SP Cruiser.

It was remarkable how his attitude changed coming around Lands End at 3AM in a 5/6, pissing horizontal rain and 2 metre swells wearing a tee shirt and shorts in the snug pilothouse.

Suits First Mate and I very well too. :)

No way we will ever go back to an aft cockpit yacht by choice.


(y)
 

Supertramp

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It's not essential to have a wheelhouse or sheltered steering, but it is a very valid and preferred choice for many.

With regard to having multiple sails, it is less efficient for pure power and pointing, costs more, but again is preferred by many for the flexibility and ease of handling.

I think this thread is about knowing what you want and enjoy and how to adapt and tune a boat to provide it.

Useful and interesting views and ideas.
 

JayDomK

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Absolutely. I've always thought that bashing back from Cherbourg in a rising 6, pouring rain and an open cockpit is an over-rated experience.

"Builds Moral Fibre" they used to say. Maybe I'm the wrong type of person but, in me, it builds a determination to get a better forecast next time
It is not a fact that a forecast will be 100% correct ;) Therefore, you need to be prepared for everything.
 
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