Journal

Spring 2009

 

 

A Fresh Start.

            I wish to thank everyone at the London A.G.M. in January who elected me as your President. Quite what I am supposed to do is debateable but I feel a certain sense of responsibility for setting in motion some changes that have re-shaped our committee and I shall play whatever part they want me to in order to keep the spirit of the Association happy and vigorous. The folk who are now running things are incredibly enthusiastic and deserve our support and although I don't have a proper job I will happily continue to get our journals printed and distributed and lend a hand on other matters if and when I am called upon to do so. I have to admit, that a land-lubber President is a pretty un-edifying prospect so I began tackling the fitting-out jobs as early as weather permitted this year and I hope to be afloat again soon.


Everything seems to come at a rush as soon as the clocks get changed and the days get longer. I used to write a 'things-to-do' list at this time of year but the length of it always looked too daunting so I am now experimenting by doing things that come to mind on a daily basis. It's a good day if I can feel at the end of it that some progress has been made. After all, I am only half an hour away from the boat. How does one cope when the boat is on a French canal or in a Spanish marina, I wonder. I love reading the stories of these intrepid sailing wanderers that we have in the Association and envy them their planning and organisational skills but I don't seem to possess that 'go-off-and-do-it' gene. Do they write job lists? Do they have a lucky star?


The boat yard I am in is well run and accommodating. It has always had a relaxed and easy-going air about it. However, I notice polite signs appearing now drawing attention to the fact that pontoons and staging can get wet and slippery and extra caution is required. When minor repairs and maintenance on and around the fabric of the buildings are taking place objects like traffic cones linked with tape give warning of potential hazards. When the crane is used yellow hard hats are liberally distributed. The care taken to prevent accidents must of course be applauded but the reaches of Health and Safety appears to have no bounds and over-rides the freedom of individuals to make their own judgement on matters of risk and reward in areas of their lives where personal decision-making builds confidence and character. At the bottom of our road is a school and when cycle training is in progress, in our cul-de-sac out come the cones, tape and notices and almost as many adult supervisors as children. The children, by-the-way, are all clad like American football players covered with shiny hard plastic protectors for every moving limb and joint. Any motorised movements are treated with extreme suspicion by the supervisors. It is odd that after all this they then allow them to risk life and limb on the highway. What's all this got to do with sailing you might say. Well, I've often sat on boats on the Continent watching enviously the apparent freedom of young and old cycling as a matter of habit. What's more, not a hard-hat in sight. But then cycling is a means of transport over there, everyone does it. Here it is a toy that children play with and do 'wheelies' on and adults ride self-consciously. You see, it's not really a very British pursuit. Sometimes I think sailing is like that. We can be a bit shy about admitting we've got a boat. Keep it quiet. I have a feeling that on the Continent, it is seen as just another pleasurable means of transport which is part of their way of life.

Pat Lacy, Steeplejack.

 

Editor's Rambling.

           Firstly I would like to apologise for the fact that the committee listings in the last journal were incorrect. I had hoped to include "stickers" with the correct names and addresses when the Newsletter was sent out. Unfortunately, due to delays in getting the newsletter out, it was very nearly time for this journal to be published by the time it was ready so, hopefully, the correct committee list will appear in this journal.

Earlier this year, former manager of Thames Marine, Ray Smith, sent me an email copy of a brochure for the Mirage 28. More importantly, Ray Smith tells me that he is still in contact with Ray Walsh, former Thames Marine director, and he has confirmed that the Snapdragon and Mirage Association may reproduce any Thames Marine information. I am hoping that Ray will be able to supply copies of other brochures for our boats, with a view to putting them on our website for historical interest. He asked me to advise members that, should they require any glassfibre materials, or coloured gelcoat for repairs, to contact Ray Smith or Steve Irving at Haven Mouldings on 01268 698823. All members are invited to ring or visit them on Canvey to discuss any Thames built boat.
I think I have managed to include a reasonable variety of articles in this journal. I already have my first article set aside for the next one. However, I don't intend to start work on the next journal before the end of September, unless I am prevented from getting on with the myriad of other things I have to do by circumstances beyond my control. Please feel free to email me with your articles and photographs, or post them to me anyway. I will put them to one side but hopefully I will find them when it is time to start assembling the next journal.
Don't forget our website. I know that Graham Polson, our "siteminder", was thinking about putting up a small piece about each of the boats in our Association on the website. I also know that there are some members' of the Association who think this is unnecessary as we already know what our boats look like. But I remember that when I was looking for a bigger boat to replace my Lysander, I didn't have a clue what an 890 looked like and, because the numbering attributed to boats doesn't always correspond with their size I had no idea of how big it is. I must have passed over several boats because I didn't know if they were available as a bilge keeler and the advert didn't say so. I didn't have access to websites then but now I, and a great many others, do their research online. I have already mentioned Ray Smith's contribution but if you have any old Thames marine brochures for our boats I am sure that our "siteminder", will be glad to have them. Graham fits in the running of our website with running his own for his business. Obviously, as a volunteer who has to earn a living, he will have to give priority to his own website but, it makes his job easier if people make material available to him. It also makes our website more interesting for other people!
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Items for the next newsletter should be sent to :- Editor@SnapdragonMirage.org.uk

 

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MAINLY TECHNICAL.

 

I am writing this in mid March and apart from finishing the antifouling and running up the engine I am more or less fitted out. I try to do as much as possible in the autumn, "fitting up" or "laying out"? This was just as well as my list contained 48 jobs. Not all were time consuming but some were 'rub down antifouling' or 'lay up engine' which contained a sub list of 14 items. Anyway I have some good stuff from David Dane with 747 CREVETTE and our Editor tells me he has another interesting item which he will include in my section, so here goes.

DON'T DRIBBLE.
I was re reading John Barker's excellent article on re engining in the Autumn Journal and noticed the photo of the new anti- siphon valve with the spigot for a tube to be led into the bilge, so that should the valve drip the salt water would be led away from the metalwork of the engine, but no pipe had been fitted. My brother in law has a Moody 31 with a Volvo 2003 which was in perfect condition; however his anti-siphon valve was the same pattern except that it had no drain spigot. This valve was sited directly above the engine, it leaked and salt water had dripped onto the top of the engine and found its way over everything until it reached the sump. This has virtually ruined the engine in my view as the salt rusts any unpainted metal and gets into the electrics. The alternator has already failed and had to be replaced. I am sure the starter motor, engine sensors and wiring loom will be next. He has now replaced the valve with one like the one in the photo but with a pipe, but it is really too late and a major replacement of components is required if the engine is to be reliable. This warning is becoming more relevant now SnapMirages are re engining.
As far as I know these valves, not being supplied by the engine manufacturer, are not mentioned in the owners hand book or workshop manual but they do need looking at every year to clean out any deposits as these build up and cause the valve seat to malfunction. One of the 14 items on my 'lay up engine list'.

HOT STUFF.
I noted that John's engine is a Beta and this reminded me that a friend with a two year old Beta experienced overheating. The problem was tracked down to the heat exchanger which was found to be choked with silt. He is on a mooring next to mine and I have a six year old Yanmar. I recall that at the Boat Show I talked to the Yanmar rep. and asked if there were any things to look out for on my freshwater cooled model. He said 'clean out the tube stack of the heat exchanger regularly'. So having heard of the Beta experience I took mine out this winter. It was certainly not choked but had quite a build up of lime scale such that, had I left it much longer, it would have been very difficult to separate the end caps from the tube stack as these were virtually glued together by the lime scale. As it was I had to use considerable force to free them. I soaked the components in brick cleaner to dissolve the lime scale, as you can no longer buy concentrated hydrochloric acid in the form of 'spirits of salts' in your local hardware shop, 'elf and safety' I suppose.

DIY Sail repairs and modifications.

We've just finished stitching U.V. sacrificial strip to a genoa and you might be interested in some of the details.
Firstly, you'll need a supplier for thread, material, two-sided sticky tape and later on, perhaps for other projects, zips, needles, sailcloth, awning material, and other stuff. Most of this is available from an ace mail-order supplier - Point North, Porth Dafarck road, Porth Dafarch, Holyhead, Anglesey. LL65 2LP. Tel. 01407 760195 Web http://www.profabrics.co.uk. This company will give you advice on the phone and send your order at a very reasonable carriage cost. You will also get a first class how-to-do-it sheet from them.
They will tell you that most of the work can be done with an ordinary domestic sewing machine. We used a basic janome machine with zigzag. No problems.
Take your time and think the job through. For example, had I spent more time on research before doing the job, I might have stitched the strip to the other side of the sail. However, because I have plastimo reefing, it can be set up to roll up clockwise or anti clockwise.
If you buy a second hand sail, it will probably come with unwanted numbers and insignia stuck on. These can be removed, a sail maker told me. We managed to do that by pulling off the numbers etc and then soaking the remaining gum like glue in acetone and scraping it off. This is a long and tedious job but it works. The glue areas can then be washed with acetone and frequently changed paper kitchen towels or cloths. Before starting the work, try a spot of acetone to ensure that it will not dissolve the sail. Unlikely, but worth being careful. I am told that when you have finished the clean off job, a good sprinkling of talcum powder on the work areas, before folding up for the winter, will be worthwhile. By the way, be very careful with acetone. It is incredibly inflammable, evaporates very rapidly and will take the natural grease and oils out of your skin, - just like that. (A job for those latex rubber throw away gloves.) It's expensive to buy in small quantities but a local factor should be able to sell it at below £10 a gallon.
One last tip, be careful to not put the needle through your fingernail when using the machine. It's a quite common injury!
Good luck. David Dane BYC 747 "CREVETTE" November 2008.

The Dremel - bless it.

About 10 years ago I bought a dremel thinking that it wouldn't get much use. Since then it's done more work than any other power tool I own. At first it was used with little cylinders of sandpaper on arbours to shape and finish wood, plastics and metal. It did so well in that mode that it was used to abrade the bilge keel bases of a 33 foot boat, standing on blocks ashore, in preparation for shoeing with g.r.p..
As time went by, other uses came into play. It can take a drill bit and put holes in difficult to get into places. TCT spiral cutters are available and they can cut a hand hole into the back of a small g.r.p. locker with ease. A 12 mm (or so) wheel with teeth on an arbour will saw and shape. Even your chainsaw can be sharpened with a kit of grinding stick and jig. Then there are those thin Ø25mm (or so) abrasive discs on arbours that will cut through bolts etc and are magic at cutting multi strand stainless steel rigging wire cleanly and precisely.
Renewing guttering around the house involved some cutting of the plastic in position up at the top of a ladder. No problem; the dremel with a t.c.t. spiral cutter, did it one handed in a flash. There are lots and lots of other jobs it can do too and many other available accessories. Perhaps the most surprising thing is that my dremel has had such a long life despite being showered with destructive g.r.p. laminate dust fairly frequently; and it's still going strong, bless it.#

D.Dane BYC "CREVETTE" 747 November 2008

Tech Officers Note;
I agree with David, however I am a cheapskate and was surprised at the price of Dremels and their 'little bits and pieces', so I got what I call a pirate version from B&Q and found it just as good. I noticed you can often get replacement bits and pieces from the tool sections of 'cheap shops'
TOP TIP.
There are dozens of boat cleaning and 'wonder products' on the chandlers shelves but apart from personal recommendations how do you know which work best? Two products are outstanding in my view. One is Y10, for removing rust stains and removing yellowing from white fibreglass, try writing your name on your topsides using a brush full of the stuff, wash it off and you will see the writing standing out as a 'whiter shade of pale'. The other is Blakes Mast Care, an oil you rub on anodised aluminium spars. It looked like '3 in 1' oil to me and I thought the shine it gave would not last long but to my surprise it lasted all season, well done Blakes.
Editor's Note: #I "killed" my first Dremel fairly early on but it was replaced under guarantee, complete with a wall mounted tool box, (which I didn't have originally), and a new set of accessories. I think this may be where the expensive tools score over the "cheap" ones.

 

News from the South Coast Branch

 

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Spring 2009

The year started with the news that the South Coast had lost its Secretary, Vicky Armitage. Vicky has done a wonderful job over the last sixteen years, 1992 to 2008, and decided it was time to step down. This was not a sudden move on her part. Vicky had raised the issue over the last two years, but to no avail. I, like many members, have enjoyed the opportunities to meet and the rallies that Vicky arranged and made possible. More through guilt than conviction I have stepped in, ad interim, to fill the role. I have not been elected, but it was my good (miss) fortune to attend the AGM where I volunteered my services. If anyone would like to challenge this most undemocratic of appointments please do so!

One of the issues that I would like to address is that of inclusivity. This year's Fitting Out Lunch was arranged at short notice and only included the regulars plus three fresh faces. For 2010 I would like to extend the invitation to all members on the South Coast. To this end I will place an advert in the Summer Magazine asking for an expression interest.

To facilitate communications I would be grateful if members could check their contact details and update them if necessary. My preferred form of communication is email, but I am happy to phone or send a letter if that is more convenient for you.


Fitting Out Lunch

On 1st March we had our Spring Fitting Out Lunch at the Waterfront Pub, Shamrock Quay, Southampton. The venue had to be changed at the last minute, but like the good sailing folk they all are, all fifteen members accepted the prevailing conditions and navigated successfully to the new venue. It was good to see three fresh faces, Don and Shirley Salmon (Rubicon) and Geoff Robertson (Pirana)

It was whilst we were assembling outside the pub; having a drink and soaking up the glorious early spring sun, that we took the opportunity to thank Vicky Armitage. On behalf of the association and in recognition of her support over the last sixteen years Vicky was presented with a card and silver Snapdragon broach.

Vicky is wearing the red jacket

Once inside, we enjoyed a good meal and much lively conversation. It is occasions like these that bring like-minded people together and the Association to life. We even managed to agree on the programme of events for the coming season.

Rallies 2009:

1. The main rally will be at the Royal Victoria Yacht Club, Wootton Creek IOW, Staying overnight on Saturday 4th July. To date eight boats have confirmed. Please contact me a.s.a.p. if you would like to attend.

2. A tender trip from Moody's Yard up the river Hamble, through the Hamble Country Park to the Horse and Jockey at Curbridge. Time and date to be advised.

3. A mini cruise around Chichester Harbour. Planned for September, date to be advised.

Happy sailing,

Bernard Hermes Tel; 02380 676534
Acting South Coast Secretary Mob; 0790 1751622
Windswept (SD890) email. hermes@rowther.co.uk

snapdragon(3)

 

 

Not for the faint hearted!

In 2003 my wife Sarah and I decided we would like to buy our first boat. I had a little sailing experience racing Dragons and doing a little in-shore ¼ ton crewing in the dim and distant past, Sarah had none. We wanted an older, solid, easy mannered, sea-kindly bilge-keeler that could take the knocks and scrapes of a novice crew, and would be competent for inshore cruises along the south coast.

Originally I wanted a Macwester 26 or similar. However, after looking at several boats, the internal space was not up to Sarah's expectations, we then turned our attention to Snapdragons. The technical Officer of the Snapdragon Association gave such a glowing account of the boats that we were instantly sold!

We bought Windswept, a Snapdragon 890, from Canvey Island in September 2003. The boat was home finished and launched around 1980. Although the boat has no sail number it is possibly one of the last Snapdragons built. The hull has the trade-mark yellow gelcoat of Johnson (?) the last boat builders to use the moulds. The boat had been clearly well used and needed some TLC.

The survey was unremarkable - no osmosis, several scratches and dings - nothing of significance! It recommended the replacement of the fixed rigging, the out-of-date fire extinguishers', gas tubing and regulator, and to renew the outboard prop shaft bearing.

Windswept was transported, uneventfully, overland to her current location at Quayside Marina in Southampton. This is where and when the fun started.

Before proceeding I need to explain that I am basically a frustrated engineer. When things do not work to my expectations I try to analyse why and, if possible, make changes. I am not a put-up and shut-up sort of person. In addition I was blissfully unaware of most things boaty. This meant that I sought opinions from anyone kind enough to offer them, and I looked at problems from first principles. It soon became clear that there are as many opinions as people. In the end one has to weigh the advice of others and to combine this with one's own intuition. There are few absolute rights or wrongs. What follows is a description of the problems and solutions that were found.
Winter 2003.

As required by the survey and the insurers, the rigging, the gas fittings and fire extinguishers were replaced. The prop-shaft bearing was of the white-metal type, of which two are fitted, one to each end of the stern-tube. These bearings are lubricated from a grease pump. I have basic workshop tools, milling machine, lathe etc. The re-casting and machining of the new bearings went without a hitch. All the seacocks were serviced, the VC tar repaired, where the surveyor had removed it, and the hull Antifouled, batteries charged, engine serviced and tested. The boat was ready for launch.
Season 2004

All systems go. The boat was launched - and floated first-time - no leaks! Great? No! The season went down-hill from there on.

I knew about the prop-walk issue, but had never experienced it for myself before, this made berthing-up fairly exciting. We have a drying berth on the lower reaches of the River Itchen. Normally we return on a falling tide. Our berth has a following tide and river flow in addition to a prevailing wind that blows us off. Needless to say the prop-walk was an aspect of the boat that I wanted to address.
The sailing itself was the most disappointing part. The performance was so poor on all points of sail, horrendous weather helm, no pointing ability and the lack of control during gusts. Sailing should be a pleasurable partnership between nature, the boat and the crew, not a battle. Southampton Water and the Solent are very crowded and subject to periodic changes in wind speed. Over a period of approximately 20 minutes the wind can vary by one or two forces and swing by 90 degrees. Under these conditions we regularly rounded-up with no control from the over-powered rudder. In busy conditions this is not just inconvenient but possibly dangerous. We found by experimentation that the boat was reasonably balanced when the main was double reefed on a full genoa. The choice was simple, speed or control, not both. We chose control - the Isle of White has never seemed so far away! This is how we sailed for the rest of the season in winds of force 3 and above.

We had problems with the deck gear. The furling rope jumped off the drum if the genoa flogged in the wind. The angle of the genoa sheets from the genoa-car to the winches was such that we regularly had riding turns - mostly when they were least convenient. The genoa sheets got caught between the stanchions and the bottle screws on the shrouds. The sheets also caught in the gap between the fore-hatch and the coach roof. The main traveller was so short that it was not possible to adjust the twist in the main; this exacerbated the heeling and rounding-up tendencies.

The rudder had a loose and sloppy feel. The turning arc was 45degree to port and 100 degree to starboard.

The Yanmar 2QM15 engine was very noisy and transmitted vibrations to the hull via the rather solid engine mounts. These were necessary due to the in-board and out-board white-metal bearings on the prop-shaft which prevented any lateral movement. Later in the season, as the days drew cooler, the engine became more and more difficult to start - yes you've guessed it! After trying everything, including having the injectors renewed and the injector pump serviced it was time to open the engine. The starting problems were due to loss of compression. Cracks were found on both cylinders between the inlet valves and the pre-combustion chambers. These had been there from the time before the boat was purchased, but the problem had been missed by me and the survey. The engine was cleaned and reassembled. Once warmed, it would start and run successfully all day. We used the engine in this state for the remainder of the season.

And… the radio reception was poor using the masthead antenna but fine with a separate antenna - obviously something amiss with the wiring.

I wanted to sell the boat, but Sarah, - bless her, - wanted to keep it!

Over the next three winters the above shortcomings, with the exception of prop-walk, were addressed. The seasons of 2007 and 2008 have been delightful, apart from the weather. I am very pleased that Sarah advised against a premature sale. I'm quite fond of our Windswept. I know the boat inside-out.

The Engine.
It is interesting to the note that had the engine not failed before the purchase it would have failed in my ownership. The reason for this was that the cooling water galleries were almost completely blocked by consolidated Canvey Island mud and salt. The engine had 1200hrs on the clock. The mud could not be cleared from the inspection ports alone. The only satisfactory method was to remove the cylinder head to gain access to the galleries.

There were no second-hand or new cylinder heads in the UK or Europe. A cylinder head would have to be ordered from Japan with several months delay. After some investigation I came to the conclusion that it would be cheaper, and better, to re-engine the boat.

I did not want a raw-water cooled engine again. A heat exchanger would avoid the need to regularly strip down the engine and would also give the option of heated domestic water - a later plan.
The options soon settled on to a new terrestrial Perkins 103-07 engine and marinisation kit. This was purchased for less than the price of the Yanmar cylinder head and gaskets! This engine had the same direction of rotation, the same torque characteristic and the same SAE bell-housing connection as the Yanmar, in addition the size was similar. All these features enabled the re-use of the original gearbox, propeller and engine bed, all greatly reducing the cost of the re-fit.

The electrics of the Perkins were wired into the existing Yanmar control panel. Only the starter switch had to be replaced with one with a pre-heat position. The gear, governor and engine kill cables and levers were all re-used.

The Perkins comes with an electrically operated fuel-on solenoid. There is no place for such a device on a boat! The solenoid was disabled and the mechanical engine stop connected up instead. It is surprising how many new marinised engines come with such a solenoid. I believe that once started a marine diesel engine should require no electricity to run.

During the re-fit the original raw-water strainer was replaced by a Vetus Water Filter. This filter has about 10 times the surface area of the original. On several occasions the original filter had become almost blocked after just 4 hours of motoring. I did not want to risk overheating the new engine simply due to a blocked filter. The Vetus has a transparent screw top that allows easy viewing and access to the filter element. The new filter was mounted slightly above water level so that the filter could be cleaned without turning off the seacock.

To address the engine vibration I made-up a double universal joint for the prop-shaft. This allowed the driven end of the prop-shaft to follow the engine as it vibrated. The flexibility of the new coupling meant that I could use softer engine mounts. There are many ways to achieve the same ends, e.g. Python-drive, Aqua-drive etc. I used the UJ solution because it was the cheapest and required no changes to the hull.

In the first season with the new engine we experienced several losses of power. This was finally tracked down to the dreaded diesel bug. The fuel tank had almost two pints of the gelatinous mess. As a precaution we now use a biocide with every fill and steam clean the tank every winter.
Weather Helm.

The sails, though tired, had a reasonable shape and thus were not directly the cause of the problem.
The following point is quite contentious amongst many cruising folk, but the advice from Kemp Sails and my experience bear it out, mast bend (some call it pre-bend). There I said it! All masts should have a small degree of mast bend. This is usually about 2 to 3 inches half-way up. The bend has two functions:

1. The bend ensures that the mast does not bend backwards and forwards in a seaway. This prevents stress reversal which can lead to early metal fatigue
2. Unless specifically requested all sails are cut with about 2.5 inches of "mast-round" to accommodate the bend.

If the mast is straight the mast-round creates a baggy sail with a centre of effort that is moved aft - hence adding to weather helm. The appropriate amount of bend flattens the sail and moves the centre of effort forward.

I choose to rig the mast for 2.5 inches on bend, as directed by Kemps (the centre of the mast is bent forward). This change had a noticeable effect, but was not the complete solution.

A rig tension gauge was purchased. The "about right" way of setting the tension leads to very sloppy rigging. In my case "about right" gave about 3% strain on the static rigging. This does not compare favourably against about 20-25% for hardened racers, or 10-15% in my case. I found no improvement in performance as the tension was increased beyond 10% for shrouds and 15% for forestay. Please note that due to the different angles of forestay and backstay the backstay must be looser. The correct tension can be calculated with a simple bit of trigonometry.

Whilst trying to set the cap shroud tension I found that I simply could not do it. This was due to the cap shroud not being in alignment with the mast. In fact the base of the cap shrouds were 9 inches aft of the mast foot. Any increase in tension on the cap shrouds simply bent the spreaders. In a blow one could see that the top of the main was blowing off to leeward. I have an aversion to drilling holes in boats. It was some time before I convinced myself that all the shrouds had to move. I used the Association's library of technical drawings to review the original plans for the 890 and earlier 29. There was a clear difference in the positions between the boat and the drawings, particularly that of the aft lower shrouds. Previously the aft lower shrouds interfered with the boom when it was 45deg off the centreline; - this had reduced the running performance of the boat. With the rigging in the right place and with the correct tension, the boat absolutely flew. The rigging change was the biggest single factor in addressing the performance and weather helm - great! At last I had a boat!!
Whilst changing the shroud positions I took the opportunity to replace all the U bolts, in line with advice from the Club on crevice-corrosion. Several had the tell-tale rusty pin-holes. It is better to do it too soon rather than too late.

The Rudder.
During the first winter I had noticed that the rudder was not aligned with the Skeg. In fact the rudder stock was about 1 inch away from the centreline of the Skeg where the rudder-stock enters the hull. This meant that there was a gap of about 1 inch on the port side and 1/4inch to starboard. This asymmetry was the cause of the asymmetric swing of the tiller. I also felt that the gap on the port side may be adversely affecting the water flow over the Skeg and rudder blade. It took two years before I tackled the rudder. When I did, the following were addressed:

1. The fibreglass foot supporting the lower bearing cup had cracked. A stainless steel foot was made to support the structure.

2. A section of the top of the rudder blade was removed to allow access to the rudder-stock and to enable the rudder to be lifted out from the bottom bearing. Two removable cheeks were made to fill-in the missing section.

3. The rudder stock was cut in the area of the section 2 above. A flange arrangement was manufactured to connect the rudder blade stock to the stock rising up through the hull. This arrangement allows for the easy removal of the rudder for inspection, painting etc - without the need for a crane!
4. The rudder blade was built-up with fibreglass to form semi-circular leading edge and asymmetrical shape about the centreline. This was essential to ensure the rudder was a good fit with the Skeg.

5. This point is also a little contentious. Most of the advice I received was to the effect that I would be wasting my time, however I persevered. A skeg and rudder blade system is similar in operation to that of an aircraft wing, - the rudder blade acts as an aileron; the deflected water flow generates low pressure on the convex side and high pressure on the concave side. If the rudder blade and Skeg combination are correctly designed most of the steering forces are generated by the "lift" on the Skeg. If this works correctly a relatively little force on the tiller generates a large steering force on the Skeg. This mechanical advantage is similar to that of a balanced rudder arrangement.

There is a problem with the shape of the Skeg on the Snapdragon 890. The leading edge is sharp and triangular in section. This shape is fine for going straight ahead with the rudder amidships. However, if one deflects the rudder then the flow at the leading edge breaks up, leading to turbulence over the Skeg and resulting in very little lift. I modelled various leading edge sections on a computer to find a shape that combined low drag with high lift over a wide range of angles of attack. The shape of the Skeg was modified by building up the leading edge with structural foam and sanding back to the required section. The foam was then covered with four layers of woven matting. At no point was the integrity of the original Skeg compromised as no material was removed. When the boat was returned to the water the effect was fantastic. The new arrangement has removed the turbulence, the loose feel, the asymmetric steering and the effort required to steer the boat. The rudder now has plenty of bite. It has never been over-powered since the change. The boat now sails with very little tiller movement or effort, although some of this is now due to the ability to balance the sails.
I ran a similar analysis on the keels. These have a very short aspect ratio and are slim for their length. The analysis suggested that very little improvement could be made. However, as I had decided to copper-coat the boat in winter 2007, I decide to complete all under water changes. To be honest I cannot detect any difference from before the change, although when heeled over the bow wave from the keel is now much smaller.

Deck Gear.
The furling problems were resolved by making a gate for the Plastimo Furling system. Some systems already come with such a gate. This was mounted at the entrance to the drum. It is now no longer possible for the rope to jump off the drum. Whilst addressing the furling gear all the blocks guiding the rope back to the cockpit were changed from plain bearing to ball bearing types, greatly reducing friction. A braid-on-braid furling line was used. The inner braid was removed on the length of line from the centre of the drum to the cockpit. This allowed a slightly thicker line to be used, which is kinder on the hands.

The riding-turns on the winches were solved by taking the genoa sheets to turning blocks near the transom. This change produces two benefits:

1. The sheets arrive at the winch well below 90degrees to the drums, thus eliminating riding-turns.
2. The straighter pull on the genoa/jib improves the shape and sends the centre of effort forward thereby reducing weather helm.
The main traveller on the 890 sits in a recess by the companionway. The original traveller only had 12 inches of effective travel, not enough to adjust the twist in the main. As an experiment I purchased an identical but longer section of traveller from RWO. By using stand-offs and longer bolts I was able to mount the longer traveller above the recess using the original holes. The new traveller stretches across the entire width on the cockpit. The extra travel gives very good control over main twist. We can now dump power if the wind blows and adjust the main in light weathers.

Prop Walk.
This is the task for winter 2008. From my investigations it seems the prop-walk can be improved by reducing the prop-shaft angle. This has two effects,

1. The angle between the water flow and the propeller is reduced thereby reducing the adverse torque produced by the propeller. This has benefits in both forward and astern.
2. In astern the reduced angle reduces the water directed onto the hull, and hence the prop-walk due to this mechanism.

For some reason the original engine and shaft were installed with an angle of 11.5degrees, although a much more shallow angle could have been accommodated. With a few simple changes to the current engine-bed and the reinstallation of the stern-tube, it should be possible to reduce the shaft angle to approximately 2 degrees.

If the changes are successful I will report back in 2009, providing I go ahead.

Conclusion.

The basic design of the Snapdragon 890 is excellent. It will never be as fast as a modern plastic-fantastic fin keeler, but it is by no means a slow design. It does not deserve the comments normally reserved for Snapdragons. I made the changes not to go fast, but because I felt that the boat was under-performing relative to the designer's original aspirations and my own. We normally take our time sailing around the Solent. The changes have made the boat far more docile and capable when the weather turns nasty. It is faster point to point and easier to sail. The feeling of safety, comfort and control make every trip more pleasant.

I have really enjoyed the learning opportunities presented by the boat. I would not turn the clock back to buy a different yacht.

I am not a great communicator, nor do I avidly read my emails, but if you have any questions I would be happy to answer them.

Please contact me at; hermes@rowther.co.uk

Sarah and Bernard Hermes, 8th November 2008.

 

"The Long Way."

Last year we spent the month of September in Fouras on the west coast of France just south of La Rochelle. We have some French friends there who help us integrate a little bit and join us for the occasional day out. Our friend, Nellie, is a member of Les Amis du Musee Maritime de La Rochelle and, as she had a job on their exhibition stand at Le Grand Pavois. She invited us to spend a day with her.
Le Grand Pavois is La Rochelle's boat show and it was a spectacular event blessed with blue skies and warm sunshine. The berths were full of gleaming new craft and the pontoons were packed with visitors. Amongst the numerous exhibitors I only recognised 2 English manufacturers Northshore and Hunter. The cheapest 'bare boat' sailing cruiser at around 26 feet long came in at €70,000. The French salesman with casual Gallic superiority said, allow for a budget of €l00,000. We moved on, enjoying the sunshine.
Back on Nellie's stand she asked me if we had been aboard Joshua. What? You don't mean... yes, it was, the 46 foot steel yacht resplendent in its fresh paintwork of spotlessly white deck and bright red topsides. The yacht that Bernard Moitessier sailed around the world in when competing in the single-handed race that started at Plymouth in 1968. As aficionados of great sailing exploits will know, he renounced the race while under sail and, having completed a circumnavigation of the globe, went another half-way round and 'dropped out' in hedonistic Tahiti. His book, 'The Long Way' explains it all.
Les Amis du Musee Maritime look after Joshua and take people out in her for day trips and longer special events. It was quite a thrill to go aboard and move around down below and meet the enthusiasts that lovingly take care of her.
Another famous vessel in La Rochelle is, of course, Calypso, renowned for the scientific marine adventures carried out by Jacque Cousteau and his team several decades ago. Sadly, she is in a terrible state of repair and efforts to restore her have been delayed by, I believe, family disputes over ownership.
Back at Nellie's home in La Rochelle we were, once again, pleased to re-new our friendship with her husband, Jean and his snappy sort of a Jacque Russell, Tibu. He used to be a film camera-man and, apart from being the chief editor of a French film starring Gene Kelly, called Les Demoiselles de Rochfort, he went on some of Jacque Cousteau's voyages to South America and his photographs, memorabilia and stories, before and after our dinner that evening, rounded off a near perfect day.

Pat Lacy


Joshua being examined by visitors

 

     

SNAPDRAGON & MIRAGE REGALIA


PRICE LIST



SWEAT SHIRTS           XL, L, M, S  £16.00
SWEAT SHIRTS           XXL (old logo)            £14.00
POLO SHIRTS             XXL, M (old logo)           £ 8.00
POLO SHIRTS             XL, L            £13.50
SHOWERPROOF BASEBALL CAPS        £10.00
COTTON BASEBALL CAPS     £ 9.00
SNAPDRAGON TIES  £ 6.00
SPAPDRAGON/MIRAGE TIES  £ 8.00
BURGEE WITH CORD & TOGGLE   £ 5.50
METAL BADGES  £ 2.50
CAR STICKERS/SURFACE STICKERS £ 0.50
BINDER FOR JOURNALS (12 ISSUES) £ 4.00
(Editor’s note; These binders are also suitable for holding R.Y.A. booklets, e.g. Flags and visual signals).  

THESE PRICES INCLUDE POSTAGE COSTS.


Shirts with old logo have the motif with the words "Snapdragon Association"; the new ones have the motif with "Snapdragon Mirage".

Cheques or Postal orders to be made payable to; "SNAPDRAGON & MIRAGE ASSOCIATION”. 
Available from Mrs. V. Griffin,
52 Merryfield, Leigh-on-sea, Essex.  SS9 4HJ.  Phone; (01702) 479965.

 

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