Since the last century yachts have used bowsprits to increase sail area and improve the balance on commercial work boats, racers and cruisers. Over recent years there has been a resurgence in the use of these.

The advantages of flying an asymmetrical spinnaker from a bowsprit include:

•More area the extra projection provided by the sprit/pod can be added to the cord length to the sail.The overlap doesn’t have to be increased

•The increase in the luff to mast angle lifts the bow improving the trim of the yacht at high speed and immersing the rudder/s deeper.

•The lack of a large overlap allows mainsail to be eased keeping the yacht more upright

•Using a sprit moves the centre of effort of the sail plan forward reducing weather helm and giving greater control at high speed.

•The spinnaker is easier for cruising or shorthanded racing than a conventional symmetric kite as it is attached to a fixed point and gibing is a breeze.Sprits appear in a variety of configurations but are generally divided into stayed and unstayed/ cantilevered and fixed or retractable. Most people will be familiar with the retractable cantilevered spars as seen on the latest ‘sportsboats’. These have a couple of drawbacks in that being cantilevered that must be of larger diameter (or carbon $$$), they intrude into the interior and are difficult to waterproof. They stayed version can, by virtue of the rigging be smaller in diameter and do not intrude into the interior however, they make berthing more difficult and also present others larger target during close tacking duels!

There are alternatives. Readers may be familiar with the ‘bullhorns’ and retracting, cantilevered spars appearing on the “Bull” range of boats (Greg Young).

Warren Luhrs first used the ‘horns’without a prod on his yacht ‘Hunters Child’the horns projected each side of the bow perpendicular to the centreline and carried a traveller carrying the tack of an asymmetrical spinnaker, allowing it to be pulled to windward to project more area when broad reaching or dropped to leeward to keep the slot open when sailing with the wind as far forward as the chute will allow.

Besides making berthing difficult and complicating the foredeck area, I believe and I am advised by several sail makers, that with modern asymmetrical sail design this simply is not necessary as the new sails are designed through the sheet and Tweaker adjusted to rotate the head around the forestay anyway.

Having designed most of my yachts to incorporate prods, I have settled on a format I find satisfies my priorities with the small compromise of restricting the length. Previously, I opted for a fully retractable cantilevered sprit as seen in the accompanying photo of ‘Moreton Bay Express’. The main inconvenience being cabin intrusion and ensuring water tightness.

With my latest designs I have designed a short, fixed bowsprit from which a cantilevered prod extends. The cantilevered prod is thus held at the outer end of the fixed bowsprit and the inner end is supported at the stem (when extended) it retracts until the inner end touches the aft face of the anchor locker and the prod is then housed and the integrity of the yacht interior is retained. As a rough rule of thumb 1/3 of the prod total length must be retained in the hull. An even simpler setup is to slide the cantilevered part into the housing before sailing and removing it after no moving parts, so simple, but bigger ‘target’ see the accompanying photo.

For each bowsprit type and for each boat, there is a separate set of design and load considerations.

Builders of carbon masts usually have straight and tapered tubes in various diameters. I have to say that carbon is not the cheapest at about $180 per meter for 50mm tube so an untapered alloy tube looks pretty good.

When designing a yacht I ensure the stem is broad enough to accept the pros. It retrofits a prod you may strike problems with the headstay/ forestay and it may be necessary to offset the hull so it is angled to the centreline thus when the prod is extended the tack is on the centreline.

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In my last article I put forward suggestions on how to rejuvenate your much loved yacht.

This month I will take the opposite tack and assume you have “seen the light” and decided to build yourself a new one. I will not go into your choice of design as I would obviously be biased.

What I will discuss are construction options. The most objective way to do this is to relate it to a specific project in this case my latest 7m trailer yacht. In a yacht of this size and type (light displacement) you have three or four options.

The most important consideration is your budget. There is no point in “champagne tastes on a beer budget.” An accurate rule of thumb is the hull and deck will cost you one third of the all up price. So don’t underestimate the finishing cost.

Your choice of construction method is certainly affected by your budget but beware most people’s initial impulse is to opt for the cheapest method. This can be deceptive. Even if building yourself, the cost of your time should be factored in. Also, a cheaper construction is directly related to lower resale price.

The cheapest material to build on is sheet plywood. The cheapest method is stringers on sawn frames (and of course you only glass the outside). But the problem is it will always have the stigma of being a sheet ply boat and be perceived as amateur built and therefore cheap. Other drawbacks are the intrusion of the sawn frames in the interior, and the time consuming job of ensuring the chines is straight and fair nothing looks worse than a wiggly chine!

There is one other consideration: having built a couple of boats this way, I found my wife was always most unimpressed by the diversity of “stuff” that accumulated along the stringers and around the frames!

Next you have laminated plywood on sawn frames and stringers. This results in a strong, light boat and removes the need for chines. Unfortunately, the aforementioned drawbacks still apply. And it is time consuming.

Thirdly, you can build in foam over a male mould. This involves setting up temporary frames with plenty of timber battens about 30 to 50mm apart, then fastening down the foam (staple or tie). Fibreglass the outside, lift the hull off the mould, roll it over and glass the inside.

As the foam is only a core the fibreglass cloth provides all the strength and load resistance, therefore this needs to be substantial (read more expensive). Also, considerable time and expense is incurred before even starting the yacht proper due to the mould fabrication. On the upside, this is the way to get the lightest possible structure.

Last but not least is strip planked cedar. This is the method I eventually chose for the 7m trailer sailer.

This involves erecting temporary frames cut from chipboard, rebating the keelson and sheer clamps into them (held temporarily) and then planking the hull longitudinally using cedar. Glassing the outside, lift the hull up, roll it over and glass the inside. With luck the tempera frames can be removed and used again.

I chose this method for the following reasons:

1) I wanted to build more than one boat

2) I did not want to have to go to “exotic” to achieve hull rigidity

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Recently I had the pleasure of racing out of Morton Bay Boat Club with some really enthusiastic sailors.

A crew’s performance is always more cohesive when the individuals are keen optimists and never give up but when it comes to the mechanics and gear aboard, “Murphy’s Law” is best applied – if it can go wrong it will go wrong!

The simpler the set – up the less chance of a foul – up. This lesson is currently proving itself in the single – handed, round-the-world race – the toughest test there is. These yachts are extreme and innovative.

Two schools of thought prevailed before the race. There were those who went all-out technologically with rotating wing mast complete with deck spreaders, canting keels, lifting asymmetrical boards forward etc.

For others the emphasis was on simplicity, lightness and reliability and – guess what? – the K.I.S.S. theory (keep it simple stupid) is prevailing, at least so far.

Mike Golding on Team Group 4 stated, “It’s clear I have good speed. My biggest concern is gear failure.”

It set the scene for what followed. Halyard chafe was solved by changing blocks and tangs on his rotating spar popped off but he nearly lost the lot when he dumped his spinnaker in the sea, the chute filled and rotated the boat around one of the mast’s deck spreaders –
but it held.

Sebastian Reidl, sailing an aluminium Una-rigged schooner Project Amazon, was forced to retire as his keel-located fuel tank had water infiltration and with the tank integral to the boat’s structure, there was no easy fix. Mike Garside on Magellan Alpha, a new Finot 50, as not happy when his hydraulic ram controlling the canting keel sprung a leak and lost enough oil to lose control of his keel. Too much air and not enough oil left it hanging to leeward and him sailing on his ear.

Interestingly, those who applied the K.I.S.S. principle (fixed keel, rig and reliable gear) were (at the time of writing) well vindicated on leg one. It would appear the race will be won and lost on limiting gear failure and weather routing.

Cray Valley – using the K.I.S.S. principle – was invariably faster than the more complicated Magellan Alpha. Sailing upwind in very light conditions there was no difference as the swing keel was not canted (on Magellan) and the water ballast (on Cray Valley) was not taken on.

Once they began to heel that all changed. The water-ballasted boat takes on water to increase righting movement and so also increase weight. The keel remains central and propeller drag is unalte red.

The swing keel yacht cants its keel and becomes asymmetric underwater to such a degree it needs forward dagger boards to make it sail straight. This increases underwater drag substantially. When close hauled it is clear the swing keelboats lose lift and the dagger boards do not fully compensate for this. Add to this the fact the “swing keelers” lack the additional “power” of water ballast and you can see why they make considerably more leeway than the fixed keel, water – ballasted rivals.

Mike Garside sailing. Magellan Alpha concluded that “the swing keel concept was basically flawed in upwind conditions”. It should be said that the swing keels should prove superior in reaching conditions.

However, I believe this race is often won or lost in light upwind conditions.

Leaving aside the questions of fixed versus swing keel, any slight deficiency is further exasperated by gear failure and complications.

Canting a keel, deploying dagger boards and rotating a mast single handedly all while charging along at 28 knots (boat speed) takes some organising and when things go wrong at this speed your are in serious trouble. Basic tasks such as eating and sleeping become impossible.

Previously I have expounded the virtues of these technological yachts but am forced to reassess my previous beliefs. At the end of the day these boats are still sailed by people and there is absolutely no point in creating a vehicle that is beyond the ability of even the most experienced crew to sail at 100 percent.

It would appear that this (as well as budget restrictions) has resulted in the increase in the number of 50-foot entries in preference to the 60s as the crew can drive the yachts at closer to their full potential for longer and the physical demands are less.

There are lessons for us all to learn from these boats – most of us like to have things to tweak, adjust and generally play with but at the end of the day, the K.I.S.S. principle wins out. If you lay out your yacht and prepare her with Murphy’s Law in mind, you will sail more comfortably with a lot lower stress level.

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Have you wondered occasionally if you are being “conned” by manufacturers into spending more money for little or no gain, all in the name of modern technology?

When setting out to decide what to build your next vessel out of you are faced with a vast array of construction methods and materials?

I would like to suggest it’s very hard to go past the tried and true wood and wood composites. When it comes to the amateur builder (or the professional for that matter)no other product is quite so “idiot proof” or as economical.

The value of light weight and high strength is well known and acknowledged, but what is forgotten (or is it ignored?) is that wood really is good. (See first editions of Boating Queensland.)

What is simpler than plywood, especially for the hull and topsides? Perhaps it’s because you use only half the glass/resin content that manufacturers would encourage you towards foam or P.V.C. cores. If the vessel is to be subjected to high impact loadings then Balsa or Ply/Balsa/Ply is quite superior. Resistance to local denting is a concern for sandwich structures, commonly happening in deck and topsides resulting in unsightly marks. In these instances balsa or plywood “Cores” offer better protection because of higher densities. Balsa core is favored by some builders for high-load areas in open 60 ft yachts and now mindful of the extensive P.V.C. core shear problems of the last generation of Whitbread 60 yachts several yachts have used balsa in high impact areas. Most boats are built with minimum weight cores that fulfil the strength requirements. Lighter cores require more complex (expensive) laminates. The basic strengths of material demonstrate that foams are fundamentally weaker than balsa.

In his basement Barry Colson is also building a high performance “trainer” he designed.The 3.5 metre “TriStar” is produced in New Zealand as a kit set yacht just like a model aeroplane by

Chris Brummel Yachts Ltd. It’s best described as a cross between a 12 foot skiff and an International Moth. Colson says he had intended to sell them in Australia, but the government duty is 26 per cent, “so much for C.E.R.!”

The yacht is catrigged (mainsail, no headsail) but has an asymmetrical gennaker for downwind powerrides. The yacht’s versatility is really appealing. I can sail her myself or with Gill for joy riding, or teach Seth to sail rather than just pushing him off the beach and relying on someone else to train him.

His next yacht is likely to feature a canting keel and perhaps rig as he admires the French designers ,“I do feel one of the things that made New Zealand a great yachting nation was their preparedness to try innovative designs. In the early 80’s Bruce Farr, Ron Holland, Jim Young, Laurie Davidson and many more pushed the envelope and Kiwis built their yachts, but over recent years they have flocked to one designs.

That was one of the appeals of Australia. It appears to me that Queenslanders are prepared to appreciate and assimilate innovative ideas.” BQ

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People who are in the market for a new boat have quite a wide range of stock designs as well as the option of getting a custom design drawn up.

The plan cost as a percentage of the overall cost of the complete boat is quite small and with a custom design you get something that really suits your requirements.

Before approaching a designer for a custom design you should first have made some basic decisions. If not, then you will not get what you think you want. Basic decisions begin with the following:
1) How much do we have to spend? (Total boat budget)
2) Where is the boat most likely to operate? i.e. on a river, lake, sheltered bays or open ocean?
3) Is the boat to be trailered or not?
4) Are you going to build or get it built? What is your skill level?
5)How long? (See No.1)
6)Number of berths?

The list goes on but without such a design brief you are likely to get a camel (said to be a horse designed by committee!).

Nothing beats being able to look over a range of similar sized yachts (preferably from the board of your chosen designer) and being able to make notes of your likes/dislikes and proposed alterations. Ask the designer if they have copies of any boat tests done on similar size boats.

Always bear in mind one day you will sell the boat and one eye should be kept on what the market is like for the style of design you are proposing – gaff rigged, heavy displacement, turn-of-the-century yachts may well be pretty to some but very few people want to own one.

When making the decision to build my current project, I would dearly have loved to have given it 500mm more beam as I know it would have been a better boat from both a performance and accommodation perspective. Even though I have no intention of trailing her the reality is that the market in Australia is far greater for trailer sailers than small keel boats (even with lifting keels). So my decision to build to the trailing maximum beam was made solely with an eye to the potential resale value.

If you are fortunate enough to be pondering a 60-footer this analogy won’t work for you but even so the market for replicas of the Bounty wouldn’t be too great either and I assume you didn’t come by your wealth by making bad financial decisions, so don’t make one with your boat!

A realistic analysis of your design’s primary use is also important. For some unfathomable reason people always ask “How many will she sleep?” Why people insist on filling up a boat with berths I don’t know.

The truth of the matter is that on the few times the boat is stacked to the gunnels with guests it is for day trips not round-the-world cruises, so the priorities should be head/shower, galley and stowage space (for the “refreshments”, snorkels etc.).

When accessing the attributes of various designs another point to consider is whether a design is available as a kit-set or hull and deck. This allows the owner to customise the interior to suit while retaining a “true and fair” hull. I know of boats that are several inches longer on one side than the other!

I have written in previous articles of the advances made in design and equipment and these elements should not be ignored. Not only do they make the boat easier to sail, they also make for an easier SALE.

For example, does the rig plan have an equal distribution of sail area between mainsail and headsail? No point in opting for a design that requires gorillas to sail. If a cruising yacht, perhaps a cutter rig with roller furling is a better set-up.

Like many things, yachts are often a compromise. However, they must be viewed in the entirety.

I believe yachts are a reflection of their owners’ personalities and as such should be individualistic. Just make sure yours doesn’t end up like the proverbial camel.

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Few aspects of yacht design have received such free rein as the design of yacht rudders – sometimes they have taken directions that have been far removed from all hydrodynamic concerns.

I have found it immensely amusing to sit in a yacht club bar listening to the self proclaimed “experts” passing judgement on the twin rudder set ups on my designs. It would appear most consider design has not advanced since Nat. Herreshoff used separate spade rudders on “Dilemma” in 1891 or Van de Stadt transom yachts such as “Zeevalk” and Zeeslag” in the 1950’s. For those on the surfing persuasion, the comparison is the move from single fin mal’s (long boards) to the smaller, lighter, three fin “thrusters” is applicable – similarly the twin rudder set up cannot be evaluated independently of the entire yacht design. When the fashion (rating rules) moved away from the 60’s and 70’s narrow sterns to the more modern broad sterned “dinghy – type” hull shapes rudder design did not keep pace. Most keel boat sailors will be familiar with the bow down – stern up aspect depicted in the accompanying sketch (Figure 1).

It doesn’t take a brain surgeon to see less than half the length of this rudder is actually in the water and working. Not only that but it is attempting to operate in the most disturbed water flow. Because this generation of yachts frequently trimmed by the head and heeling to a certain degree at the same time the upper part of the blade often emerges from the water, so the blade must therefore be long.

The rating of the period (50 – 90) penalised fuller bow sections in fact Bruce Farr, Paul Whiting and others actually had designs with hollow water lines and this tended to exasperate the problems.

The modern “open” designs are the complete opposite. The hull buoyancy is more evenly distributed along the hull’s length and in fact when sailing upwind these boats exhibit a bow – up attitude.

All this leads logically to a rudder or rudders located at the position of maximum waterline length and horizontal to the optimum angle of heel.

Now this can only be accomplished with either a single canting rudder (which has been done) or twin rudders. The arguments I have heard against twin rudders don’t stand up to scrutiny.

1. The people “bagging” them have never sailed a (properly designed) twin rudder boat.
2. There is not more wanted surface with twin rudders, in fact there is less! – For example on a modern 8.5m yacht a single rudder
would be between 4.5 and 1.7 metres below the waterline when static the twin blades are only 700 – 800mm deep.
3. There is less drag as at optimum heel angle (15 – 20 degrees) only one of the blades is in the water ie 50% less drag.
4. Safety is enhanced as you can have a “spare” blade.
5. When comparing a single transom hung rudder with twin rudders the access from the water (or a dinghy) is hugely superior with the twin set up.

In summary unless you have sailed yachts with twin rudders you are in no position to comment – I’ve certainly sailed yachts with one rudder. Sailing a twin rudder yacht in 35 knots of wind both upwind and downwind is a two finger experience.

Footnote: To reduce ventilation and improve the effective aspect ratio of twin rudders I recommend fitting a fence or cavitation plate positioned to form a prolongation of the hull. As shown in figure 2.

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