(a single seat thames skiff called a whiff gig)

The full article to be found in watercraft magazine Jan 2002

I've always been interested in curves and aerodynamic shapes but as time goes by the family grows, and so do the bills, so ideological things you were going to do drift into memories of college days.Well, four kids, a business to run and every reason to have no time to do these things, I've decided (yes, you've guessed it, I'm 40!), I must build a boat, come what may. First reaction from all who know me - 'not another rocking horse!'. A full size merry-go-round horse I started 10 years ago languishes in the corner requiring only one more week to complete.

My thoughts on building a boat; Not a motor boat, I have enough noise in the workshop. Steam would be great, although, I realised I could spend a fortune just sorting out the steam side of things. Not a yacht - I've never sailed apart from a very scary few hours further out from Southend Pier than I care to think, in a choppy sea, in a very old mirror dinghy with my best friend who had little experience and couldn't swim! Besides, if I get my design or making wrong, I would like to feel that any poor soul in my boat could at least swim or float to shore.

This left electric and rowing. Electric may be later but what caught my eye was a local and graceful craft - a Thames skiff. I started off on the wrong foot by trying to obtain plans for a Thames wherry and after many calls to various museums realised that a Thames wherry and Thames skiff are very different craft. Basically, for those who wish to know, Thames wherries go back a long way and were the taxis of the past before bridges over the Thames and before even the steps to walk down to them. They had a rounded stern and an angled but straight entry to the front, beefed up with some very solid timber so that when rowing hard into the shingle and when the tide was on a run the keel wasn't torn off. These craft were quite round in section, usually entered from either the front or the back, were for professional oarsmen and very robust. At the end of their working lives, wherries were broken up and burnt because like taxis,trawlers etc were not for the public but working craft. The only known example now in existence is a half size replica in the Science Museum. From this a full size replica was produced by Mark Edwards, a boatbuilder at Richmond-upon-Thames - a font of knowledge and decent all round chap.

What I should have been asking about was a Thames skiff, a more genteel boat of the 1800's which came in all manor of sizes and developed into the recreational craft at the end of that century.

A number of these fine craft grace the Thames today, still working as hire boats over 100 years after they were built! Finding information still proved difficult because anything termed 'small boat' has been put in store waiting for the new museum in Cornwall to open next year.

I found one beautiful original example in the form of a half size presentation in a display in Kingston museum and although warned by staff, accidentally set off the alarms that guard the exhibit when trying to get a better look! Mark Edwards came to the rescue when trying to find true sizes for a Thames skiff. 'Working Boats of Great Britain' is a book that took its author 10 years to research and is absolutely jam packed with accurate information, not to mention lengths, breadths and details of boat interiors.

Now, to how I wanted to build this boat with an eye to possibly filling one of the quiet periods of my working year. One of the obvious drawbacks to making a boat is the cost of the labour and in my case the amount of time taking up valuable floor space in my workshop. So, from the little I have gleaned from what I have read and seen, I thought I would add my twopenneth worth to boat building from a furniture maker's point of view.

The first problem is the labour and time in setting out. I though that if computers can draw in 3D, number crunching being right up their street, and if shapes can be wrapped, then they ought to be able to be unwrapped - this was, I have to say, a couple of years back when adverts for such things were not so often seen. I found a couple of answers which would both do the trick, one specifically so. Multisurf is a professional boat building programme but at a price. The unwrap feature adds a couple of thousand dollars on to a $4,000 price and is only available to Windows systems. Then there is Form.z which is a modelling and 2D programme , an all round programme which would fit my Mac as well as PCs.

As I had never used a drawing programme 3D came as a shock - 120 icons on the left hand side, each with a set of options which affects every other icon. After an expensive one-to-one lesson and a new Mac later (my old Mac had a nervous breakdown when trying to handle the software, to cut a one and a half year story short!), I found that it would be easier to design and build carvel rather than clinker. So I thought 'why not'! The museum example in Kingston had its exterior lands smoothed to give the appearance of carvel when it was sent to be exhibited in Chicago in the late 1800's so if it was seen as the height of 'posh' then it wouldn't be out of keeping now.

I entered the lengths and breadths of the skiff from 'Working Boats of Great Britain' into the computer and tidied up some of the most obvious errors before skinning each plank using the curves and techniques I had learnt, then pressed the magic button to unwrap each one (well, it worked that easily eventually!). So now I had my planks and soon followed a 2 1/2' model, a one tenth scale version of the family skiff I had in mind. Using a Dremel and a scrape I created male and female profiles on the aeroply model and assembled my first craft without any tampering to the cut planks. So now I had eliminated the need for taking lines for planks on this boat and I hope in any other boat I enter into the computer.

Next on my list; planing the lands on clinker craft or angle on carvel would be time consuming so they had to go. I looked at speed strip and from my industry, good old tongue and groove and came up with my tolerant version of an off set half round with a deliberate rebate. This was so that as the planks changed from vertical to those which met both positively and negatively at up to 30š they would require no planing, just a different sized gap. This external rebate has a number of advantages; it can be raked out, cleaned then filled with faring filler either coloured black or a neutral brown to provide a genuine visible water tight joint, a strong line to emphasise the plank lines and a means of regulating any local blips when you just plane things a little wrong. To check that the sample joint was good, and had bonded well, my wife's present of a bird table for the garden sported a nice carvel roof with decorative joint detail! Next problem; -because for the computer design to work well carvel style, the planks ideally should be continuous and not pieces scarfed together during building. A simple scarf joint has never been to my mind particularly safe or easy to produce tidily so I used a variation on a birds beak joint with very shallow entry and exit. Not achievable by either hand or router, my trusty spindle moulder came to my aid.

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The joint faces involved are so long, thin and fragile on planks with a thickness of only 7mm I removed the bulk with a router so that I didn't destroy myspindle cutters or kill myself when spindling end grain with blanks that would likely be banned by some EU directive. (I have now had proper versions created to keep fingers safe!) Their advantage is that once clipped together you could hold jointed planks from one end without glue or clamps and they would remain flat and in line because of their interlocking nature. This allows you to create all the joins for the boats planks in one day. One little extra point; if the internal corners are left very sharp they actually provide the point at which all breaks occur internally - this acute angle needs to be softened to even out the stresses and so the planks should break more randomly and not always on the glue join which is the ideal, especially in tight curved plank situations. Next, glues; The problem with the two glues I had in mind were that they both, for different reasons can take up to 24 hours to set sufficiently to remove the clamps (depending on temperature). Resorcinol, the red/black stuff that is truly waterproof is good but not tolerant of any voids and is very brittle unless used with filler products. Epoxy glues, and in my case, West System, will keep your hands very warm and start to smoke within 5 minutes if left in a pot on a warm day but spread it thin over 20' joints and after a few hours you begin to wonder whether you remembered to put any hardener in - an anecdote I won't go in to, suffice it to say it involved a new lad, 10 drawers in 30 clamps, a Friday afternoon and a delivery driver telling me he had 2 hours to get on the last available ferry to France, and the words 'Hardener? - What hardener?'!

This is where my new toy comes in - a microwave oven on a stick. Actually a handheld radio frequency generator which helps cure certain glues by exciting their little molecules enough to cure through internal heat generation. That's the good news; the bad news is that it hates resorcinol glues, sending lightning strikes through the glue and timber that a thunderstorm would be proud of, and if not, just fizzing like a pint of cheap lager leaving weakened voids. As for West System, it doesn't even touch it leaving it totally unchanged. Enter Coconut Shell filler powder, very fine and as for its waterproof qualities you only have to go down the garden and look at that coconut you put out for the birds when you were a child! One other interesting property is that it makes resorcinol behave and, yes folks, it does make a difference to West System giving it that internal heating it requires. True, it's not instant but it does knock considerable time off the cure. If those nice people at West System let me come on one of their day courses I'll bring my new toy along for them to play with!! This was not bought solely for the boat project but as an aid to the workshop as space, clamps and continuity- as in - what shall I do for the rest of the day while the glue dries!.

When it actually came to the boat my 26' skiff seemed a little large for my first attempt, plus there were rumblings in the ranks that had progressed from 'rocking horse' to 'if you want us to work here you'll have to build it in your garden', so after thinking about things, costs and another chat to
Mark Edwards, I settled on a carvel version of a Thames whiff gig which his guys were making. This meant we could evaluate if I was making any savings on time. A whiff gig is basically a single rowing skiff between 18' and 21' long, 3' wide with outriggers and has a seating position to the rear for the passenger to operate the rudder and a small seat to the front, or should I say,seat back as you sit on the removable decking. The rowing seats of some are interchangeable having a rolling seat one side with a fixed seat to the reverse. The lines are similar to a Thames skiff although sleeker in plan, and one less plank.

3D Design

There are a number of points to remember when trying to create your planks in 3D. One is that the plank is , for drawing purposes, infinitely thin, therefore you have to decide whether the face you are creating is on the inside or outside of the boat and where each corner lies. This is because the computer willnot successfully unwrap a full thickness plank as, in a curve, one face is longer than the other (tension compression and all that stuff). The first plank is especially important because amidsips the groove on the keel has to be drawnbelow the line in order to accommodate the thickness of the plank. However, when it reaches the front, this changes as the plank rotates through 80o and meets the stem and stern. When considering the width of the planks plus where the joint lies in relation to the imaginary 3D drawing, you have to allow for the extra bit on the male half of the joint. You also require an extra amount at the middle of the boat because when the angle changes and the planks become part of a circle the outside face grows in comparison to planks in a flat plane. This modification may seem small but when added together over 6 planks the difference can be half an inch which can throw measurements out completely . Although reasonably accurate I'm sure the first plank is the most susceptible to inaccuracies as the inside and outside of the plant are subject to different forces; one to compression; one to tension adding distortion.

What's more, it doesn't help when the programme doesn't deliver the goods! For example there is a separate icon hidden away in Form.z which triangulates every square panel that makes up a plank. This in effect stops squares becoming diamonds when unwrapped creating totally inaccurate shapes - well, no-one told me! The triangulate option in the unwrap command did not produce what they call 'true planarity' leaving me with a duff first plank which I only discovered after cutting all the planks. Luckily for me, only the first plank was affected and once I had found the true planarity button elsewhere I was back on track and only had to modify the 1st plank. One real downside has to be that you have to have complete trust in the drawings in order for the process to work and when it lets you down you have no-where to go. After my knock in confidence I did not truly trust the new plank and did not pull it tight at the front when glueing up. This has resulted in a 1/4' blip which runs through all the planks fortunately this is not noticeable but when each plank is applied there was a natural overlap. The biggest surprise to me was that although there is a slight convex curve to the keel of 11/2' there was over a 2' concave curve to the first plank. If you place the first two planks left edge to right edge you see a 4' gap, the complete opposite to what I had expected, and I suppose a result of the almost 80š twist in the first plank when clamping up. It was not until the last clamp was applied that all the differnt gaps and voids miraculously disappeared. As the later planks were applied it was reassuring to see each one fall into place and match the marks placed on the sterm and stern. The transom can pose a problem when predicting the angles required for each plank tofit snug at a compound angle. This is overcome by taking two cross sections, one at the back and a parallel cut 1' in, then printing the true view. This gives the inside and outside profiles of the transom which can be glued to the back of the blank . Due to the vagaries of reality it is not spot on but it is close enough to give very good direction. With my new found caution I cut the outside profile of each part of the transom and profile in conjunction with its respective plank, cutting just enought of the next profile so as not to make things difficult later when the plank is glued.

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Making the hull

As I have said, space is at a premium in my workshop so I needed a method of manufacture that could be moveable and easily dismountable. I wrapped my planks around cross sectioned panels which were clipped to a central beam with secondary notches so that the keel could be clipped into these panels. This differed quite considerably from Mark Edwards' craft which was built the other way up using a beam above to help prop loose floating planks into their proper position. My keel had no capping piece into which the first plank was nailed. I relied on my frames and a rebate routed into each side to the depth I had allowed when the 3D drawings were first drawn. To make sure these were positioned accurately on both sides an MDF panel with the profile was clamped to an oversized keel, one side routed and then small router bites taken out of the waste timber all the way through at intervals to give mechanically accurate marks to work to when transferring to the other side and templates..

Using the same principle as the curved and rebated joints, I used a simple half round section on my first plank to coincide with the routered groove, leaving only the last three feet rectangular otherwise when the angle becomes shallow there would be an awkward external gap between the outside of the plank, both at the stem and stern where the plank is vertical. At this point, some good old fashioned woodwork came into play trading off thickness of plank and thickness of keel remaining. My modified first plank did retain a defect which was that although its profile in the critical area - the first four feet forward and aft, were OK, I did not correct the total width which was 1/4' shy over the whole mid section. This meant that to prevent the guiding cross section profiles from failing to 'guide', I had to remove all corners - not exactly best practice, but gets you there.

During the whole of construction nothing held the keel other than the 2' x 1' notches in the profiles and the planks themselves. This has good and bad points; the good are that any severe distortion through bad clamping or shape of a plank is immediately apparent, so that there are no great surprise twists at the end when everything is taken apart; the bad is that if things are meant to be restrained until the final plank is fitted so that a balanced shape is achieved - I'm in trouble! This became obvious on the first plank. If I had glued one left then one right I doubt the second plank could have salveged the banana that I would have created. So with the help of my very understanding wife they were both glued in at the same time. After that, the next couple were glued in one at a time but with the counterparts held in place to balance the stresses. After three of the six planks, the shape was rigid enough to withstand the slower shaped planks, without balancer.

After the fifth plank, the sixth and last. This will not be Brazilian cedar (used for both lightness and durability in a wet environment and its very good impersonation of mahogany, plus just that little bit stronger than Western red.) The last plank is mahogany and is approximately 14mm thick, started in the same manner as all previous planks but instead of the curved joint a rebate with decorative detail just in case and a good position to imitate the decorative details I've now seen on original craft. So that the plank does not look clumsy at the front and rear the thickness is reduced to approximately 10mm. There are a few different ways of finishing the top edge, either a reinforced inside edge, harder to empty of water when turning over. A reinforced outer rubbing strip or just a modelled profile which ties in nicely with the outriggers. As I wanted to get ahead but did not know the final position of the outriggers, I plumped for an outer strip tappered to 2/3 height at the stern and 1/2 height at the stem and vitually nothing in thickness, correcting a visual error at the stern where in plan I had made the profile slightly concave which was pointed out to me by Mark on a visit - well actually I turned up at his workshop, bundled him into my car saying, 'Come see, come see!'. Second childhood is not only for the really old. Suitably impressed with the theory I continued with the more traditional aspects of construction. Ribs and bracing made from English oak, in this case some planks left over from a commission using planks from a tree which fell in the 1987 storm. These were nailed and roved another new activity for me.

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With the fine copper pins I used earlier as a belt and brasses fixing at stem and stern after the West System had cured, I became very aware how easily bent and fragile they are. For pins I find the best method is to cut the head off one, drill, using this as the bit then hammering in a pin lubricated with West System or a little tallow (although not when final finishing!), the true holding power gained from the last 3/16' unable to be drilled as this part of your drill bit is in the chuck. For the thicker, square pins a hole drilled so the diameter of the drill bit matches the distance across the flats seems to do the trick although when through oak not always enough so a second hole the full diameter is drilled part way. I wasn't sure whether I should be making the oak ribs thicker, thinner or the same as for clinker as my knowledge of whether my carvel hull was stronger because of the continuation of curve or weaker as I did not have the benefit of 11/2 x thickness on each joint. I took Mark's advice regarding the keel., He advised not to bevel the 1' wide keel down to the 1/2' required for fitting the 1/2' D section steel/brass trim until after the hull was complete. This allows for a small degree of cheating if the keel is out of line. I found that when stretching a line the full length of the keel there was a bow of less than 1/8'- when spread over stem, middle and stern - not a great deal to redress.

The major source of information used whenever the call came 'What now?' was a set of photos taken of a craft built at the turn of the century and a more modern construction with added extras! These extras included a small drawer below the passenger seat and a wicker back with arms. There appears to be a tradition for the boat builder to have some free expression when creating the small step just before the transom and expresses itself as decoration on the transom and support for the front edge of the step. This reminds me of the church carvers who would be allowed a degree of artistic freedom when carving under the folding seats of the choir stools, a ledge giving some apparent seated support when standing called a miserichord.

The interior has taken longer than it should for since I know little about the cause and effect of any actions I may take when fitting out I hesitate and muse at every stage - not good when trying to time my actions. The rowing position is of great concern to me for if I position things poorly rowing will be far from pleasurable, especially as the craft is directed at the talented amateur. I have commissioned outriggers from a respected company, Ian Neville Racing, and have resisted the temptation to pre-empt the manufacture of the ribs which relate to the fixing until the riggers are made so that I can make the timber fit the metal rather than fudge a join. This will inevitably be refined if any further craft are built. Luckily I have a neighbour who used to row to national standard who I hope will give me a few tips. As there are a number of coats of lacquer to apply to both sides I had to tiem work in the morning then lacquer last thing so that it would be dry the next day. When collecting the outriggers and rudder bits I asked if Ian knew where I could obtain some oars, looking whistfully at some gathering dust on a shelf. After some advice on seating/rowlock positions and some more whistful glances, hands were shaken, a deal was done and I departed the proud owner of, not only shiny stainless steel outriggers and rudder fittings, but a pair of racing sculls as well.

When the hull was unsupported I noticed how much it could possibly flex and was glad I had left the keel full internally. I also thought that the bracing for the first couple of planks which were at the same level internally would have been vulnerable to cracking if the boat did flex, so I dovetailed rather than crosshalving all the joints to help preserve their integrity. As each set of ribs were fitted (each thick rib was cut, the basic profile inspired by the cross sections and then split in two for symmetry), the hull became more rigid in its length. The hull finally firmed up when both sides of the hull were tied together with the seat and rowing position. When the wicker back and side panels were made I felt a little more on homeground. For speed I used mahogany wedges primed with West System to hold prewoven cane in position. The cane had to be presoaked as it stretches when wet. The arms hinge so that when removed from the hull they can lay reasonably flat. When slotted home the arms are prevented from lifting with brass hooks.

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Although a little bit of an extravagance I bought full 'D' section brass trim for the keel and had a fretted brass copping to the nose tig welded to one end. The heat generated is very high and localised preventing distortion and change in hardness, in the bulk of the material. The screws holding the trim left proud when filed flush leaving enough head for later removal.

A few more phone calls and the distances required between foot, hand, bottom and rollocks were settled and undertaken. Time was pressing if I were to launch my first boat before the end of the summer and as I got closer to finishing I became more focussed and a little blinkered - determined to finish in a sensible timeframe.

One and a half weeks to go and I felt confident enough to book a launch at Richmond boathouse. Hurried phonecalls provided a small crowd of neighbours, colleagues and anyone I could stop in the street to cheer the launch of my slender craft. My dear wife christened her with a small bottle of champers, the second half of the bottle being sent to the bottom of the river to appease the river gods - apparently they should not be deprived of any pleasures.

I became her first passenger with Mark rowing - I have never rowed a boat with a sliding seat. A few tweaks of the oar collars which were still set for more experienced hands and it was my turn. Living the dream is sometimes as good as you imagine it to be and this was it! Hardly a ripple as I glided acrosss the Thames with a very nervous but trusting passenger - my wife.

I had an offer on the day from a passing American tourist but thankfully not followed through as the object of the exercise was to see what response there would be to both my method of construction and whether a carvel build solid timber hull would cut any mustard with potential customers used to being offered ply clinker and GRP hulls. My interest is mainly the hulls. The interior is too longwinded for my workshop and far more suited to the hand tools of Mark Edwards and his loyal band. Well, the Head of the River Race fast approaches - we will see!

Oh yes, the name, the name is as the title suggests - 'Yolanda'. Many years ago the series 'Pennies from Heaven' appeared on our screens with an actress called Yolanda Palfrey. I thought this to be a beautiful name and vowed if ever I owned a boat or maybe built one, that is what she would be called and now, 20 years on, 40 years and 6 months old - one of these life goals has been achieved. Now perhaps I had better earn some money so the kids can eat!

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