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Barry Colson - 0417 606 352

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A Tale of Two Boats

January 13, 2020 by Barry Colson Leave a Comment

This is a comparison of 2 x 550 monohulls designed by myself to two totally different specifications built in the same year.

About 3 years ago I was approached by a mate of mine, Mick Unwin, of Brisbane to design him an up-dated 550 designed sports boat. Mick had built an 8-metre cruiser/racer design of mine “Fuzzy logic” previously but with a young family resulting in limited time and budgetary constraints he was after something smaller and less demanding. After discussions I drew up a development of my Spider 550 design without the restrictions placed on a production boat. His hull shape features a single chine above the waterline blended in to a high stability hull form.  Not long after the design was settled and Mick began building, I ripped my Achilles tendon in half and ended up on my back not walking for 3 months. During my recuperation it became apparent I was never going to hike out or put my feet under toe straps again, I was lucky to be walking. At the time I had been sailing a 580 trimaran I had designed and built but walking on trampolines was not going to be an option so it was time to look at another monohull. Having most recently finished the design for Mick that was a logical starting point but one of the benefits of designing and building for yourself is there are no restrictions or preconceptions other than the budget and the fact I could not hike out so it had to be a “sit-in” boat. Having always admired the open designs and the open 40’s in particular I have watched the development of the scow designs and so settled on a “scow with a bow” thus “MissUnderstood” was conceived. I wanted her to have an almost retro-style whilst Mick wanted “Fuzzy Logic’ to have a contemporary look.

Mick had settled on foam and glass as the construction technique for his new “Fuzzy logic” with a modest but strong laminate using double bias woven cloth set in epoxy resin with a tailored laminate specification built over temporary MDF building jig. Now I was to build in the back yard which is always challenging and more so with my narrow side access so I decided to build mine in two halves, down the centreline as done with several multihull designs. The scow hull form with vertical topsides and flat bottom panels made this a viable option so I chose to build her in fibreglass sheathed sheet plywood. She was never going to be the lightest boat out there but it was a practical method built over permanent frames with no stringers, chine logs or gunwales, she was effectively stitch and tape. When eventually fitted together I was relieved to find the two sides were within 3mm, not bad for being effectively built on a beach under a tarp.

It would be difficult to find two more different yachts of the same length. Mick had gone for the now-predominant vertical lifting board with a 120 kg bulb whilst I wanted to be able to sail mine up the beach. I’m also of the opinion that for ¾ of most sailing the bulb provides little contribution to stability and is effectively drag until you are sailing up wind in 15+ knots. In hindsight a vertical lift bulb-less board would have been easier and more efficient but I solved the drag of the long centreboard slot with a plug fitted once the board is lowered. MissUnderstood relies on form stability which she has in bucket-loads whilst Fuzzy logic relies on crew weight and the bulb. To try and negate some of the weight difference in the construction the board in MissUnderstrood weighs in at about 80kgs compared to the 125 kgs of Mick’s.

The cockpits in both boats are huge, MissUnderstood’s is 2.70 metres long from the companionway bulkhead to the transom. To maximize the waterline sailing length I extended the hull in the form of a boarding platform out between the rudders effectively making the hull the same length in-line with the back edge of the rudders. Both boats are fitted with twin rudders as is standard for my designs with Mick choosing twin tillers while mine has a single tiller with cables and a tie bar. This is currently being modified with the cassetted swing-up rudders being replaced with shaft rudders which will swing up as per open 40’s & 60’s so that I can fill in the stern cut-outs currently necessary for the blades set up in the cassettes. Mick has fitted the gudgeons off-set on the side of the rudder boxes rather than on the front. My reasoning being to enable his vertical lifting blades to have lead in front of the pivot points, balancing them up. This has been done on other designs and works well.

With the rigs, as previously mentioned, Mick had an existing skiff rig with carbon mast set up as is now common with no backstays as per the 16 and 18 footers. The original mainsail was cut down with a maxi fat top head. We managed to get pretty close to the original design concept and that of the Spider 550. With MissUnderstood again I went in the opposite direction. I needed a short but efficient rig to get the centre of effort as low as possible to accommodate the lack of bulb. Having developed a rig for my trimaran I was impressed with its efficiency so went that way. Mine was an aluminium wing mast out of a Tornado set up to rotate with no proper spreaders and a single set of diamonds. The mainsail is basically rectangular with little topmast and no backstays. The mainsail luff measurement is about a metre less than Fuzzy Logic’s. As I wanted to be able to sail mine single handed, I decided on a self-tacking headsail but to ensure I had a similar sail area required some lateral thinking. MissUnderstood is set up with two headsails. The no.2 is set at the stem whilst the no.1 the forestay is moved out approximately 500mm on to the bow sprit. This has to be done on the beach but is quick and easy and both headsails remain self-tacking.  As I’m maturing with age and am not quite as mobile as I once was, I have gone with a furling code zero which is truly a wonderous thing. I have a gennaker for those light air runs but seldom use it.

When all done both Fuzzy logic and MissUnderstood were run over weigh bridges. Fuzzy is 80kgs lighter and certainly faster having cleaned up her division in her first regatta at the Magnetic island race week but MissUnderstood is still warming up and for an older bloke’s sit-in boat she performs admirably.

Colson 550Z “MissUnderstood”
Colson 550 MU “Fuzzy Logic”

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Prods and Sprits

September 2, 2013 by Barry Colson

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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Constructive Arguments

September 2, 2013 by Barry Colson

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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Murphy was a realist

September 2, 2013 by Barry Colson

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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Are we Being Conned?

September 2, 2013 by Barry Colson

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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HORSES OR CAMELS FOR COURSES

September 2, 2013 by Barry Colson

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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