John Perry

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John Perry

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Have been interested in boatbuilding and sailing from early years, but I am not sure how that came about. My father was fond of camping, walking and mountains, but not particularly of boats, whilst my mother was dead against anything to do with the water.

My first boat was a Mirror dinghy, acquired second hand about the time that I left home. I soon started to explore the Essex and Suffolk estuaries using a camping tent rigged over the boom. Although Josephine and myself are now lucky enough to live within a few minutes walk to the lovely coast of South Devon, I still have a fondness for those muddy creeks that is hard to explain. We have been making a pilgrimage back to Essex at least once each year since moving to Devon.

A year or two after getting the Mirror dinghy, I discovered the Hostellers Sailing Club, at that time known as the Youth Hostel Association Sailing Group. I have remained an active member ever since and have edited their website for the last eleven years. When I joined HSC it was a very lively group with a wide age range and sufficient active sailing members to support sailing in members boats and in the club owned boats most weekends through the summer. There were also monthly meetings in London and training courses, as well as the walking and social weekends held at Youth Hostels through the winter months. The club is one of very few, if any, that promotes dinghy cruising rather than racing or just pottering in boats. As with so many clubs, the membership has aged and dwindled over the years, but I still find it a very friendly group and so far I have not come accross any comparable club in Devon. Although the HSC membership is now quite few, we get a high proportion of the total membership coming to most of our organised events. Our week long summer dinghy cruises are the highlight of our program and we have had some fabulous trips on those years when we have been lucky with the weather. Prospective new members are of course welcome - the days when sailing clubs have waiting lists for new members are long gone I think.

About 1974 I decided to design and build my own boat for dinghy cruising and having the use of a 'mainframe' computer at a college in London I wrote some software to generate a hull form and to develop the shapes for plywood hull panels. This was not CAD as we know it today. The computer had no screen to display drawings, all it could do was print numerical data, in my case dimensional data, on a line printer. I used this numerical data to mark out my sheets of plywood. I did do some 'back of an envelope' kind of sketches to work out how things could fit together, but there were no proper scale drawings and certainly no lofting, the design went straight from long lists of numbers to sheets of plywood that were then joined together by the same 'stich and glue' method as on my Mirror dinghy. I should add that there were errors in the software that caused some funny bumps in the bow area, apparent on the finished boat to this day. This must have been one of the very first uses of CAD in small boat design. I had a vague idea in my mind that I would use the finished boat to sail from Essex to Holland, probably returning by car ferry since the return would be against the prevailing wind and in any case my holidays were probably too short to do that passage both ways. With that trip in mind, I built the boat with a hull shape and a lead centreboard to encourage self righting, although it probably would not be totally self righting without some assistance from the crew. I also gave it a self draining cockpit and a large amount of dry storage so that I could carry plenty of cruising equipment. Since I then lived in a small flat in London, my only option for building a boat was to borrow my parents garage and that dictated the 4.5m length of the boat. I now think that was good choice of size considering that I have only a small car with which to tow it and until I met Josephine I sailed it single handed. I never did sail to Holland, at least not yet, but I/we have sailed that boat around much of the UK coastline as well as a number of passages across the middle section of the English Channel and along the coasts of Normandy and Brittany. When I built the boat I was thinking of it as a bit of an experiment and I anticipated that within a few years I would get tired of it and want to build something different and probably larger. However, even though I enjoy woodwork and would love to build another boat for that reason alone, the first boat I built seems to meet our requirements so well that I have never been able to justify another one. You can only sail one boat at any one time.

Despite the above, I have built a couple of other boats, but only as an experiment, not for regular sailing. I felt that to justify my membership of the Amateur Yacht Research Society, I should do some 'funny boat' sailing, so I built a couple of experimental hydrofoil sailing boats having just two hydrofoils one ahead of the other. This was well before members of the Moth class first tried that configuration. I think that the Moth sailors went this way through a desire to circumvent the class rules, whereas in my case the idea stemmed from thoughts about how bicycles have mainly supeceded quadricycles and tricyles. Most people, had they never seen a bicycle, would imagine it to be a totally impractical device suitable only for circus tricks, but the test of time shows that for most purposes it is actually better than human powered vehicles having larger numbers of wheels. The success of the Moth foilers confirms that the same may well be true of sailing hydrofoils, at least in the small sizes. I built two hydrofoil boats, which by chance were about the same length and sail area as a Moth dinghy and the second one even had 'wings'. The first one had no wings and the idea was to sail it using a trapeze wire, 'water starting' it in the same way as does a skilled windsurfer. Unfortunately I had never sailed with a trapeze wire prior to building this boat and although I had tried a bit of windsurfing I had totally failed to execute a 'water start'. Hence it is not surprising that I never got that boat to become foil borne for more than a hop, inevitably followed by a big splash. The next version with wings did better and although I never practised enough to properly develop the technique I did get it to 'fly' for a reasonable distance on a handful of occasions. I will never forget one occasion when I launched it at Grafam Water in a breeze that I thought was too light to do more than drift around the lake in displacement mode. There was little more than ripples on the water, but to my astonishment, when I turned onto a broad reach the apparent wind built up and suddenly the boat was foilborne and stayed that way for most of the width of the lake, perhaps a few hundred meters, much the longest hydrofoil run I ever achieved.  At first my eyes were transfixed on the horizon, concentrating on keeping a steady angle of heel slightly to windward since I had discovered that letting the boat heel to leeward, like a normal boat does, lead to instant capsize. It was some moments before I dared to take a glance downwards to confirm that the hull was well clear of the water and the hydrofoils were silently slicing through the water leaving virtually no spray or wake. An unforgettable experience but I guess that my real interest in sailing has always been cruising, i.e. going places in sailing boats, so I kind of lost interest in these experiments after a while. I am really impressed seeing from 'U Tube' how the Moth sailors have refined the 'bi-foiler' concept and developed it into a craft that can beat a similar sized conventional dinghy round a race course under most conditions, perhaps all conditions.

The above covers my amateur boat design and building. My engineering career has included a large number of different jobs in many different industries, the number of jobs being mainly due to a succession of redundancies resulting from insolvency of small companies and the general collapse of manufacturing in the UK during my working life. I have worked in many different industries, eg construction, software, instrument making, vending machines, ship repair, orthopaedic implants, fibre optics and, yes, for short periods, yacht building. I designed some of the deck gear for a sloop of nearly 50m LOA, I also did hands on laminating of carbon fibre yacht masts and in recent years I have had occasional involvement in the construction of an amazingly powerful luxury motor yacht. The latter one is not the kind of craft I would want to see too many of, but it does throw up some interesting design issues.

Anders Anders
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Re: John Perry

Hi John and welcome.

You wrote
the first boat I built seems to meet our requirements so well that I have never been able to justify another one.

Do you have some photos of that boat. First of al because I like the idea of home design but also because it sounds scary with a boat that doesnt justify the building of another.
John P John P
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Hi Anders
Here are a few pics, selected at random, I have loads taken over the years.
At Chausey
This one was taken at the Chausey Islands, after we sailed there from Weymouth stopping at Alderney and Gurnsey.
In Harwich Harbour
This one at Harwich good few years back, sailing about full speed.
In Coflette Creek
This one just a few months ago, in Coflette creek in Devon, just a few miles from where we now live.

Its proved to be a nice boat for what we mostly want to do with it, but its not perfect. There are a few changes I would make if I started again. Like most peoples first home designed boat, it turned out a bit heavier than I had intended it to be, so I kept the designed displacement by reducing the amount of lead in the centreboard, which must have reduced its ability to self right to some extent. Another time I could probably reduce the weight of the hull structure and put that lead back where it was supposed to be. The general proportions and the internal layout are fine for what we use the boat for, I would change nothing there at all. Rig is a bit quirky, a gunter with a rotating mast but it does work and the short mast is handy, but a standard Bermudian would be simpler in some ways.

Having too many boats seems a bit wasteful to me, but perhaps I shouldnt say that here! I suppose if people who like boat building but not sailing can sell the old ones to people who like sailing but not boat building that makes sense, could put the boat building industry out of business though. Trouble is, I get the impression that home made boats are generally unsellable these days, in fact in the UK its illegal to sell a newish one.

Maybe I will build another boat or two some day, I do hope so anyway. I have a few ideas floating around. (well, a long way from floating at this stage)

John
Anders Anders
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Re: John Perry

Its a nice boat John. How big is it? I´m impressed that you´ve crossed the channel in it. How long does that take?
Paul (admin) Paul (admin)
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Re: John Perry

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A nice boat indeed - very similar hull shape to MilliBee and I bet she is quite stable yes?

-Paul

John P John P
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Hi Anders
Its 15 foot long, not counting the transom hung rudder.

I sailed that boat over to France a few times actually, there was a period of several years during the early '80s when I made it my annual two week holiday sailing single handed from the Solent area or from Weymouth to Normandy or the Channel Islands, also one year sailed Paglesham in Essex to Dunkirk and Calais and took a look at the canals that connect those ports by an inland route. Looking back on it, I am amazed that I got back on time at the end of every holiday, this may well have been down to luck. A bit more recently, Josephine and myself have done two holidays sailing over to France, the most recent in 2002. On that occasion I was between jobs so we were able to go away for about six weeks and had a very nice time. We were less in a rush than when on a fortnight holiday, so we felt able to stay in port and go sightseing as we pleased. On that occasion we returned by car ferry rather than under sail. No long trips since 2002, but I may soon be no longer working full time, so I wonder.

As for how long it takes to sail a dinghy accross the channel, we did it once in just over 12 hours, that was the quickest, from Portland to Alderney. However, it mostly took a lot longer than that. The very first time was in light fitful wind (very much better than too much wind of course) and that took well over 24 hours, maybe something like 36 hours, it was a long time ago so cant remember exactly. I do remember that since this was long befor we had gps I got pretty lost and ended up sailing a lot more than the straight line distance and I did fall asleep at the tiller at one point. One of the difficulties is that if you are used to a normal daytime job for 50 weeks of the year then suddenly set off on an overnight passage in a small open boat its hard to cope with the sudden change of routine and sleep pattern. I think those amazing sailors, mainly French, who do the long distance single handed races almost live on the sea between races.  
BrianP BrianP
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Re: John Perry

John, did you ever make plans available for your boat? Ballasted dinghies are so rare one wonders if it is because somehow the concept does not work, sort of worst of both worlds, rather than best of both worlds, ie the lightness and performance of a dinghy with the safety of a ballasted yacht.

To find out for my self I bought a Laser Stratos Keel, 16' dinghy with 100kg of bulbed ballast. She was terrific out in the Solent. She was ok in the shallow water except her very deep rudder would knock up and she was then difficult to control. My Wayfarer did not behave like this.

It did prove to me that the concept worked very well. It was great blasting down the Solent, knowing if we made a mistake, which we did, she would only heel so far, then slow up and recover without throwing us in the drink.

The Stratos is a very expensive boat, so a design for home building would be great. Especially one so proven as yours.

Brian

John P John P
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Well, I dont think it is a particulary stable boat, at least not in terms of 'initial stability', that is stability at small angles of heel. At 5'6", the beam is probably a bit less than average for a 15foot sailing dinghy. Also, as you see from the first picture, the chine is above the waterline along the full length when the boat is level and the righting moment does not build up much until that chine is well immersed. However, the advantage of this is that when the boat is really well heeled, 60 degrees and more from upright, the bouyancy is mainly in the upper part of the topsides, the side bouyancy tank supporting most of the weight of the boat. This gives the weight of the boat a rather greater leverage to stop the boat going right over than would be the case with a boat having a firmer bilge. This was an intentional design policy to produce a boat that would recover from a near capsize situation, but it is possible that I may have gone a bit too far in that direction, its hard to know without building a whole series of boats identical except for hull shape and then sailing them all in a range of conditions.

John

adminHBBR wrote
A nice boat indeed - very similar hull shape to MilliBee and I bet she is quite stable yes?
-Paul
John P John P
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Re: John Perry

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Brian
I would agree that when you add a ballast keel to a dinghy sized boat there is a real possibility that you will, as you suggest, end up with the worst of both worlds.

For sailing boats in the size range that we are discussing, moving the crew weight off centre is a much more effective way to gain righting moment at normal sailing angles of heel than is adding ballast.

There are a few small boat designs where the internal arrangement prevents the crew from moving off centre, Matt Layden's Paradox design would be one. In this case the righting moment has to be mainly provided by a combination of hull shape and ballast and it is clear that this results in a boat that is a bit
slow under sail. Not that I am against the Paradox, I think it is a brilliant design, but it is not quick to windward.

So, if we are seeking performance under sail in a small monohull boat, we will be relying on mobile crew weight to provide most of the righting moment that we need for normal sailing and we will probably aim to sail the boat as upright as possible. Hence any ballast we add in the form of a ballasted centreplate or drop keel will I think be mainly of use to avert a capsize in those situations when things have got a bit out of hand. Assuming that we are considering permanent ballast rather than water ballast, we will have to carry that ballast every mile that we sail, just to have it available on a few, hopefully rare, occasions when it could perhaps be extremely useful. We also have to accept extra weight when the boat is on a road trailer and assuming that we have the ballast in some form of drop keel we have the considerable complication of arranging a lifting mechanism and a means to lock it down when we go out to sea. Water ballast is a possibility but to have the desired effect it will need to be a lot heavier than a lump of lead at the bottom of a drop keel. For most purposes the ballast option is probably not worthwhile, but if you are intending to do coastal sailing, or even offshore sailing, it may be worth considering.

Most dinghies can be righted from a capsize by the weight of one crew member on the centreplate, so that seems a good starting point to determine how much ballast is needed. The amount of ballast you need will depend to some extent on hull shape, as I tried to explain in previous message, a  narrow slack bilged boat needs significantly less ballast to make it reliably self righting than does a wider firm bilged boat. The location of bouyancy compartments/bags in the boat is also a factor. I think my boat has about 60kg of lead in the lower part of the centreboard and that certainly does right the boat from 90 degrees and beyond in calm water and with no crew on board. However, it is less ballast weight than the boat was designed to have and another time I would aim to have a bit more for several reasons. One is that you dont really know where the crew will be after a capsize - they could be desparately clinging to the rigging, which wont help the boat recover itself.  Brian says that the Stratos has 100kg in a bulb keel, that sounds good.

As for boat plans, as I said in my first message, I did not produce scale drawings when I built my boat. I have long intended to draw up some plans retrospectively. If I do get around to it, I would probably be unable to resist the temptation to make a few changes, so whatever I draw might be better than the original boat, but could also be worse. I do quite like doodling boats and in recent years have mostly done such doodles with a 3D CAD package, but I tend to want to doodle something new rather than something thats already tried and tested.

BrianP BrianP
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Re: John Perry

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Reading about your boat, here,
http://www.btinternet.com/~sail/boatbuild03.htm

she has about 75 kgs lead ballast in the bottom of her centreboard. Interesting that you also mention her initial tenderness and then how she firms up. Sounds really good. i was so interested in this concept after owning the Stratos that I had a single handed version designed called the Haze 4000. Yet another boat I failed to build.

http://www.bluelightning.co.uk/Haze/haze01.shtm


Probably too racy for me know anyway.

Brian
BrianP BrianP
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That key issue you mention John, about having the ballast there when you need it.

My son and I sailed the Stratos in strong downwind condition. It was thrilling to blast down the Solent, yet knowing the keel would look after us. As an instance, I was gybing off Yarmouth and jammed the long tiller extension against the hull side. Over she went, but only so far and then steadied giving me time to recover and sort myself out. I reckon the keel stopped us going over more than 5 times in these blasting sessions.

Also, sailing back upwind up the Solent to Keyhaven, was much easier with the keel weight. We only had to sit out a bit, no real hiking out, just comfortable sitting on the side decks. She pointed so high as well. We raced her just once against the local Wayfarer fleet. She outpointed the racing Wayfarers easily. We won the race going from about 4th to first on the long beat home. I believe the reason was that her large dagger board built to carry the 100kg bulb created much more lift than the smaller centre boards.

I felt that a ballasted dinghy really can be the best of both worlds. The Laser Stratos just had a very wide stern which lead to control problems when the rudder came up in shallow water.

Brian
John P John P
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Re: John Perry

Hi Brian

It seems there is a discrepancy in the figures I have given for the weight of ballast in my boat centreboard. The fact is that I am guessing a bit since I only ever had the centreboard out of the boat on a couple of occasions in the last 30+ years and I didnt have scales to hand at the time. I expect it is something around 60 to 75kgs.  The centre of gravity of the lead is not quite as low as with a bulb keel, but it would be diffiucult to make a bulb retract properly so that the boat can go in really shallow water and can take the ground level. What I might be able to do another time, should there be another time, is to make the keel side profile swell out at the bottom, that is like a bulb keel in side profile,  but not in end on profile. That would however mean that there would need to be a small houseing projecting up from the cockpit floor inside the boat, maybe a removable rowing seat could be fitted to the top of the houseing, it would be in the right place for that. As well as the lead in my boat there is a nine gallon water tank under the floor that we try to keep fairly full for sea passages, original design intention was to have two such tanks, but only one got made. I think there is just about enough ballast, but a bit more would be even better, the 100kgs that you had in the Stratos sounds a good figure to aim for.

What is a  Haze 4000? from the picture it doesnt look like a boat with a ballast keel?

John
BrianP BrianP
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Re: John Perry

Hi John,

the Haze 4000 does have a ballasted centreboard. Keith Callaghan specialises
in designing Merlin Rockets and small trailer sailors. After enjoying the
Laser Stratos Keel so much, the Haze was an attempt to produce a single
handed version. We felt that ballast would be between 40kg and 70 kgs. We
were keen not to have the total weight of the boat beyond what a single
hander can haul out up the slip.

http://www.bluelightning.co.uk/Haze/Haze4000%20study%20plans.pdf

My recollection is that the centreboard was made using a lead bottom
section, wood top section and all covered in a SS skin. I think.

A period of my life without income meant she was never built, much to my
regret. Alec Jordan now works with Keith to cut kits of his latest Merlin
Rocket designs.

I have this theory John, that capsizing sailing dinghies keep the popularity
of dinghy sailing to only the people who think capsizing is ok. How many
people would sail yachts if they capsized so easily! It's similar to cycling
before mountain bikes came along. Only people who would accept uncomfortable
drop handle bar bikes road. Then mountain bikes changed everything. More
upright riding position, first class gears and soft tyres.

If dinghies "did not capsize" they dinghy sailing would be hugely more
popular.

My experience proved that a ballasted dinghy can be enjoyable, fun and far
safer - just as you also have proved. With modern light weight epoxy ply
construction the total  weight of boat and ballast can be handled.

Water ballast is enjoying some popularity, but the ballast is very high. The
Stratos would recover well with 100kg bulb at the bottom of the held down
daggerboard. A friend with a Hawk 20 had to stand on the centreplate of his
capsized Hawk to recover her, even though she has 600kg of lead in her
bilges.

Brian

BrianP BrianP
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Re: John Perry

Actually there is a new design of singlehanded ballasted racing dinghy, the K1 which is quickly becoming established. So perhaps things are changing. When the design was proposed there were the usual detractors on the yachts and yachting forum, but from this pictures she must be selling well


Hull weight is 50kg and keel weight is 60kg, sailing weight 125kg, about the same all up weight as our local 12' Scows.

http://www.k1sailing.com/

I cannot actually think of an equivalent available cruising design, for wood epoxy, to your design John?

Brian