How to turn a Traditional Motorsailer into a Sailing Boat

Bodach na mara

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I remember reading the article but I had no intention, at the time, to consider a motor sailer. I am now a bit older and am losing my patience with sailing boats that have taken ages to make moderate passages in the light winds that have been common over recent summers. I'll be upstairs for a while till I find that issue of PBO.
 

rotrax

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I spent a bit and fitted a little used Facnor furler with a new forestay and had Pete Sanders make a big code zero. I modified/remade the turning block on the Starboard side to allow use of the OE Lewmar 40 power winch for outhaul, trim and furling. A new Lewmar was fitted to the Port side which is handled manually.

Sods law means the only perfect conditions we have tried it in were in 2022. We had a 5-7 knt true wind beam reach across Belfast Lough using the code zero and full main. We achieved between 4.5 and 7 knots.

Without the code zero the iron jib would have been on. With the standard sail plan it aint worth pulling 'em out unless you have at least 12 knts.

With a stronger crew I might have used it more, but it was always too much for me to be confident with such a big sail-it is a full 175%.

Our boat, an Island Packet SP Cruiser, is a heavy shallow long keeler with a decent rudder. Easy to handle with two aging sailors. The new code zero is a bit intimidating though!

First Mate and I know Laminar Flow and his lovely partner. He has worked wonders with 'Big Anne' and she is a credit to his intelectual power and shipwrighting skills.

Well Done!
 

Laminar Flow

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I noticed the use of both "," and "." as decimal separators (SA/D given as 17,98, but later the boat was described as a 31.5-footer). I've worked with Spaniards that use "." for thousands and "," for the decimal separator.

ISO and IUPAC use either comma or period, and the spaces for thousands on both sides of the decimal. 1 000 000,000 01 vs. 1,000,000.00001 US practice.

Interesting, and potentially confusing, as an engineer working in several areas. You are never sure if you are looking at a typo. Decimal separator - Wikipedia
I am sorry about that. Part of the trouble is fat finger syndrome, the other is that I bridge two cultural worlds and at times things just get a little mixed up.
 

Laminar Flow

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A good point, and if a motorsailer was designed to sail well to begin with you shouldn't need to make radical changes. I think the Fisher 34 suffers (and benefits) from a very heavy displacement for its length, and its not especially beamy. Something like 4.8 tonnes of ballast, and 11.5 tonnes displacement! A lot of 37's have a bowsprit similar to yours presumably to up the sail area, and bring the centre of effort forward.

The Cromarty was designed by the same team who designed Fishers, but over 10 years later. I like to think they transferred a lot of good ideas from their earlier designs while choosing a very different hull shape and a lighter overall weight (8.5 t vs 11.5 t for the 34). 8.5 t is heavy enough and I get upset if we heel more than 15 degrees. But nothing punches through seas like heavy displacement which is when I wish for the Fisher, or Colvic.

I fully agree about the challenge of finding up to date pilothouse cruising yachts that can operate independently for several months without cans strapped all over the deck. Not easy to achieve under 35 feet.

Sirius 35 and Bestevaer 36 offer something near but well beyond my means. Interesting to see a modern motorsailer based on a modern wide bowed design. Peter Goss's Oddity is interesting and embodies a lot of good features but as with many modern designs loses out on the sheer displacement benefits.

The Fisher 34 has a D/L (displacement/length ratio) 433, the 37 is at 407, the CW32 has one of 360 and the rather heavy CW 35 is at 437.
Compared to our Boat the 34 has a much higher water plane loading and one would expect her to be more comfortable in a seaway. However, they do have a reputation of being a bit rolly, something our boat definitely is not. I suspect this is due to the Fisher's slack bilges and deeply immersed, underwater volume.

We have found that speed definitely quietens down Ann's motion in a seaway. At pretty much exactly 6 kts, buoyancy and inertia seem to cancel one another out and all the speed bump & pot hole notification immediately cease. Fortunately, we quite easily reach this speed and to enter the state we have come to call "gliding" (you have to say it with a Southern U.S. accent, think Scarlett O'Hara with a lobotomy)

The Watson steering end has to be one of the crudest I've ever come across, especially on something that is expected to make some sort of reasonable progress under sail.
I have yet to find another boat, produced in series, to which more owners have thought to tinker with the steering system. Yet I have experienced considerable opposition, outright denial and, not to say, gas lighting on various CW fora for pointing this out, voicing any sort of criticism or suggesting remedy: "What makes you think you know better than G.L.Watson ?
Simply profiling the rudder and streamlining the deadwood not only brings all the benefits detailed in my video, but additionally offers a significant reduction in overall resistance by itself: The deadwood causes the same resistance as a fixed 3-bladed prop, while the flat rudder adds 2 more props to the equation at 6 kts and a 10 degr. rudder angle.
At this stage I kinda think the proof is in the pudding ...

I have sailed and traveled on boats with decksalons, dodgers (fixed and soft) and wheelhouses proper. I can state that there is absolutely no comparison in visibility, functionality, comfort and convenience between a wheelhouse and the former two.
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.

Best, A.
 

fredrussell

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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.
As has been said on just about every thread you’ve ever started on here, the “entire yachting industry” (or the vast majority of it) is/are making yachts for places where there isn’t much Scottish rain. They make boats for where the vast majority of boats get used.
 

srm

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We made the observation in the North (Scotland, Orkneys and Shetlands), . . . . .
One summer's evening I greeted a visitor in Stromness Marina (Orkney) only to hear a miserable tale of woe; the weather was worse than winter wherever it was that he kept his boat in the south of England. Having lived most of my working life in Shetland, then Orkney, I did notice that generally we only had a "proper" summer every three or four years. On the other hand I have enjoyed some very nice day sailing across the mid winter holidays in Scapa Flow.

Scandinavian yacht builders seem to produce cruising boats more suited to northern Britain, though I usually had much better weather on the west coat of Norway, inside the islands, than in home waters. We got bad sunburn on our first Norwegian cruise and soon learned to time our sailing to take full advantage of the afternoon sea breeze.

One the west coast of Scotland the yacht density increased as one sailed south. In more recent years it seemed to be mostly bigger charter yachts busily motor sailing, presumably to visit as much as possible in the time available.
 

Supertramp

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And you find a lot of heavy displacement wheelhouse/pilothouse yachts up the NW coast of Canada where there are some similarities to Scottish weather (but with hot summers added in!).

You don't need a heavy, pilothouse yacht to do it. We spent many "summers" in a 26 foot Centaur with no sprayhood and everything damp with the occasional gift of a sunny day. You got used to it. The weather is part of the character of the place. But I recall seeing Miller Fifers, Fishers, Speys and wondering what it was like on one of them. Decades later, and able to choose what size and design features matter, I respect Laminar Flow's choices and modifications.

It's all down to what features are most important to you, and then whether you can find a new build that will offer them (and that you can afford). Failing that you find an older design, take on the maintenance and repair, and settle for whatever compromises it contains or modify it to suit you better.

I am surprised that the Westerly Duo, Haber, Voyager, Moody Eclipse type designs have not caught on more. Down to cost to produce and whether they can sustain a business.
 
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RupertW

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As has been said on just about every thread you’ve ever started on here, the “entire yachting industry” (or the vast majority of it) is/are making yachts for places where there isn’t much Scottish rain. They make boats for where the vast majority of boats get used.
I agree but I’d put it the other way round and say the entire Scottish sailing community has missed the point of sailing, which isn’t the kind of sport you want to do in more than occasional rain, and never in the cold.
 

flaming

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As has been said on just about every thread you’ve ever started on here, the “entire yachting industry” (or the vast majority of it) is/are making yachts for places where there isn’t much Scottish rain. They make boats for where the vast majority of boats get used.
This.

The "entire yachting industry" is out to make money. They do this by making things that sell. You sell more boats to people who live in places where you can sail in a T-shirt than places where you need a wheelhouse...
 

srm

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I agree but I’d put it the other way round and say the entire Scottish sailing community has missed the point of sailing, which isn’t the kind of sport you want to do in more than occasional rain, and never in the cold.
But then I would have missed all those days ghosting in light airs and bright sunshine, to say nothing of the many magical nights - the only boat in a mirror calm anchorage when it never gets dark as twilight lasts from sunset to sunrise.
 

RupertW

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But then I would have missed all those days ghosting in light airs and bright sunshine, to say nothing of the many magical nights - the only boat in a mirror calm anchorage when it never gets dark as twilight lasts from sunset to sunrise.
Fair points - I miss the long twilights in mid-Summer even though I’ve never sailed north of Felixstowe.
 
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oldmanofthehills

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Rather than worry about why so few smaller wheelhouse boats for 3 season British Weather are designed to sail well, I am taking Laminar's suggestion and am going to hydrodynamicaly amend the stern our LM27.

The number of doghouse additions to boats increases as one goes west and north in the British Isles but having tried that, the Navigator wanted wheelhouse and the LM is what we could afford that suited her non navigational needs

Template prepared. Probably use closed cell construction foam and glass it in but investigating sheet size cost and best adhesive or resin. Should be fun and may seek more advice.
 

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Laminar Flow

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Rather than worry about why so few smaller wheelhouse boats for 3 season British Weather are designed to sail well, I am taking Laminar's suggestion and am going to hydrodynamicaly amend the stern our LM27.

The number of doghouse additions to boats increases as one goes west and north in the British Isles but having tried that, the Navigator wanted wheelhouse and the LM is what we could afford that suited her non navigational needs

Template prepared. Probably use closed cell construction foam and glass it in but investigating sheet size cost and best adhesive or resin. Should be fun and may seek more advice.

Let us know how that works out and watch your prop clearances. LM, by the way, offered their 27's with an optional Becker (Flettner) rudder.

Best, A.
 

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Refueler

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As I have commented elsewhere I have increased the Sail Area of our LM27 by 13% by means of a short 1m bowsprit and 20% increased genoa area.

On the right tack in the right airs she does have about a 7% increase in speed compared with her old sail in the same condition. Very pleasurable and I am glad I did it.
However it was partly done to move the centre of effort forward as the LM27 suffers from inconvenient weather helm which is hard to manage as the spade rudder is too small. (She still has slight helm even with fully reefed main). I have increased rudder area upwards but the profile of the hollow GRP rudder was nearly ok as it was, so did not change it - however it did not greatly improve handling.

But and its a big but, as a shallow draft long keeler she is slightly more tender and furling and reefing is critical much more than our old heavy Westerly ketch, and I have made it possibly more so. I practice we just reef the main early and tweak the genoa, though its then hard to get ideal genoa shape

Further more I have not improved windward performance as if I press beyond about 50 degrees she simply goes leeward more rather than the apparent heading.

So perhaps I need to improve the profile of the deadwood though it seems not a poor as the Colvic W looking at the pictures

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.
 

oldmanofthehills

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Let us know how that works out and watch your prop clearances. LM, by the way, offered their 27's with an optional Becker (Flettner) rudder.

Best, A.
I have long ago seen pictures of fletner. Not sure quite how it works as fletner add on seems to remain fore and aft despite rudder turning port or starboard, anyway doubt I could source or afford one. It seems to have more of rudder ahead of the steering shaft than I expect, but no doubt that is offset by the fletner add on
 

Refueler

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I noticed the use of both "," and "." as decimal separators (SA/D given as 17,98, but later the boat was described as a 31.5-footer). I've worked with Spaniards that use "." for thousands and "," for the decimal separator.

ISO and IUPAC use either comma or period, and the spaces for thousands on both sides of the decimal. 1 000 000,000 01 vs. 1,000,000.00001 US practice.

Interesting, and potentially confusing, as an engineer working in several areas. You are never sure if you are looking at a typo. Decimal separator - Wikipedia

You want to be in my job !! Not only the , vs . but also I get from Inspectors where they leave a space instead of , for millions / thousands etc. But at least then they put a . to separate the decimals !!

ie

1 000 000.000 = 1 million
 

Supertramp

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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 think twin furlers with a big overlapping genoa on the front and a 100% on the inner is a good way to go. Twin keelers are often prone to weather helm or at least are very sensitive to the sail balance. Very marked on the old Westerly 22 as the lee keel dug in and the large skeg/unbalanced rudder started to lose grip with heeling.
 

B27

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I remember reading the article but I had no intention, at the time, to consider a motor sailer. I am now a bit older and am losing my patience with sailing boats that have taken ages to make moderate passages in the light winds that have been common over recent summers. I'll be upstairs for a while till I find that issue of PBO.
My patience isn't the problem, I need to get home before the tide drops too much.
For light airs progress, I'm looking for a bigger spinnaker. to fly from the masthead on a longer pole.
Sailing along the coast, a lot of passages can be dead runs., or variable with a fair element of dead down wind.
Which of course means low apparent wind.

I was tempted by a nice long bowsprit, but this winter has got away from me.

More sail area close hauled would be nice sometimes.
I don't see a cheap route to that, For my bilge keel boat anyway.
 

dancrane

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You sell more boats to people who live in places where you can sail in a T-shirt than places where you need a wheelhouse...
Nothing in all of UK boat-owning, justifies non-sailors' jeering humour, better than most yachtsmen's self-deception that our weather supports the purchase of boats designed to be sailed where T-shirts really are ample attire.

The low number and low popularity of boats that are suited to our mostly unreliable or disagreeable climate (by offering inside and outside helms), shows that having swallowed the sunny marketing, owners of open-cockpit yachts are resolute in defiance of learning what was obvious...

...because on changing boats, they refuse options permitting indoor helming when it's fuggin' freezing. They prefer to own a boat that even they don't want to use for six months out of twelve, and which for many weeks and weekends during the better months, they'll avoid on grounds of rotten weather.

No longer owning a boat (and feeling wiser, warmer and wealthier as a result) the determined defence of this preference really is very funny. ;)
 
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Laminar Flow

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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.
 
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