(Please note this chapter was written before the  widespread introduction of carbon masts. Thus it is somewhat dated now.)
 

The Hull
Masts
Sails
Fitting Out

It has been said many times by many people that boat speed makes you a tactical genius. With the Finn, boat tuning is not quite as critical as most classes, although it is fundamental at International level. For an average sailor, using an off-the-shelf rig and with a modicum of sail setting sense the boat can be sailed at almost maximum speed capability - adequate for the racing requirements of most club sailors. However to step up a gear and produce the boat speed necessary to win at National and International level a programme of fine tuning and minute refinements is essential.

To compete on equal terms with the top sailors is beyond the means of most sailors because of the high turnover of masts and sails that is required to find that all-essential fast gear. However the standard gear is perfectly adequate for all other sailing. One good point about the Finn is the longevity of the hull, not just in its structure but also its racing life. It is not uncommon for Finn hulls to last for several four-year Olympic campaigns and still be winning. Your primary need therefore is to find a good hull and only then to work with it using a selection of masts and sails if you wish. Provided the rig you have is in a reasonable condition most Finns can be fine tuned to gradually bring their boatspeed up to compete on more equal terms with the top sailors.

There are many variables to play with in order to get the optimum setting for maximum speed so it is necessary for novice Finn sailors to understand and comprehend what effect a change has and how to change settings to produce better speed. You also have to look at the whole picture and make the whole thing work together, not just in little bits. A Finn rig is very sensitive to change. A mere 1 cm can make all the difference between an average Finn and a fast Finn. Therefore meticulous and accurate setting and recording is required in order to get the best out of your boat.

One of the most important boat-preparation stages is to correctly fit the boat out for ease of use when racing and with adequate power on the control lines. The subject of control lines is discussed in some depth in this chapter.

A methodical and meticulous process of gradually tuning the boat can pay big dividends on the race course. However there is not that much to tune on a Finn if you decide to stick with one set of gear. Starting with the basic settings of mast rake and mast position you need to find the settings that produce best boatspeed together with easy boat handling. Apart from the mast position, all the other tuning is done by the sail controls lines once out on the water. Producing the correct sail setting can be the single most important factor in producing boatspeed and every effort should be made to perfect the art. This is mainly gained through experience in looking at a sail, assessing its shape and then knowing what to do with it if it is the wrong shape by repeating known fast settings.

This chapter outlines the processes involved in getting a competitive hull, producing a matched rig tuned to yourself, and setting the boat layout around you so that it is comfortable and efficient to sail.
 

The Hull

Before buying a Finn it is first necessary to decide at what level you want to aim. The choice available is widespread both in terms of hull shape and price. Basically the faster the boat is, the more expensive it is likely to be, generally irrespective of its condition. Hulls fall into three main groups, for example the older hulls such as Fairey, Pearson, Tiptree, Elvstrom - these boats are no longer that competitive although they may be perfectly adequate for general club racing. They will usually be quite inexpensive. The next group of hulls include Raudaschl, Taylor, Mader etc. - these are ideal for club racing and can be competitive at National level. The top level of boat includes the Vanguard, Devoti, Lemieux etc. which will generally be relatively expensive but will be competitive at all levels and one of these is essential for anyone with International aspirations. Other hulls such as Lanaverres and Rogas fall somewhere between the top two groups.

The differences between the different hulls shapes is at best minimal. The tolerances in the hull shape only allow for +1cm. Some hull builders will go for the maximum length, maximum beam and some will go for the minimum. Some hull shapes have a flat section under the transom to promote planing and some have a deeper section. Some will have fine bows to aid upwind performance, while others will have a fuller bow. Perhaps the biggest difference between the hulls is in the weight distribution. Modern Finns are built to produce the best weight distribution figures when the boat is measured while keeping the overall weight down so that maximum lead correctors can be inserted in the boat.

With the Finn, the secret seems to be to produce hulls which have good local stiffness, particularly in the centre and lower portions, but light in the ends and especially in the deck; overall they should be flexible against tension. The possible exception to this is in the bow section of the hull abeam the mast. It appears that if this area is too stiff the rig does not work in harmony with the hull, especially in a chop. The hull needs to have a perfect underwater finish, and once you have got it perfect, don't drag it up the beach! The centreboard bolt should be maximum aft and the centreboard plate hole should be maximum forward in order to get the Centre of Lateral Resistance maximum aft. The mast deck ring should be maximum forward to reduce the natural weather helm. Your hiking position must be comfortable with wide webbing on the toe straps to spread the load and ease the circulation, so that you can hike out all day. The centre of gravity should be as far aft and as low as the rules permit.
 

Masts

Rig Critique
Finding the correct mast/sail combination for you is arguably the most crucial consideration when preparing a Finn for racing. Without a matched rig you will never get the best out of your Finn. Extensive testing of rigs is beyond the means of most of us, but there are some good rigs to be had secondhand if you look in the right place, although sometimes they can be found more by luck than design. The procedure is usually to find a good mast that suits your weight and then to try and find a sail that matches the mast. Changing masts to suit a sail is not normally recommended.

Procedure
The following is in a rough order of priority. Obviously one without the others is a waste of time, but you have to start somewhere and you might just as well get the basics right first.
 

• Find the right mast to suit your weight.
• Find a matching sail.
• Position mast correctly within the hull.
• Balance the forces.
• Fine tuning whilst racing.

Mast Tuning
Although most Finn sailors will use the mast that comes with the boat and just get along with it, there comes a point where it is good to assess the mast that you have and try to find a way to improve boat speed and boat handling. For example the mast may be too stiff or too soft for your weight. It may not bend very well, it may be too heavy or any number of reasons.

Since the advent of metal masts, Needlespar have been at the forefront of their development with its world-renowned 3M section mast. This mast is designed with a long bottom cylindrical section and an upper conical section that can be produced to the desired length and quality, carefully selected and finally joined to make a successful unity. With the introduction of carbon masts, there has been a certain amount of reverting to the past, with the masts capable of being tailored to suit the helmsmen. Instead of shaving and gluing wood, the carbon fibre is added or shaved to produce the required bend characteristics. This is not realistic on aluminium masts.

Mast Design
The ideal masts for Finns would be to have minimum weight, minimum centre of gravity height, minimum size and to have a flexural response perfectly matched to the helmsman weight, the wind speed and the sail. The first two requirements, weight and C. of G. are easy targets to aim at as the class rules specify the minimum allowed, but the real challenge to creative engineering lies in providing a reliable strong low-windage solution that reacts with a uniform radius of curvature to the leech tension fore and aft and the wind force sideways.

In order to provide sufficient strength for running, the sideways stiffness must be approximately double the fore and aft stiffness. All Needlespar masts have this characteristic although some models achieve the relationship by shape (i.e. oval) and others by increase of wall thickness. The maximum wind force that can be captured by helmsman  is clearly controlled by his weight and the stability of the boat, but when going to windward most helmsmen have to let the sail out or pinch a little higher into the wind when overpowered. Downwind with the helmsman sitting well aft to prevent the bow submerging there is roughly double the stability and control can be maintained again until overpowered by lack of weight.

The mast must be strong enough at deck level to resist a bending moment fore and aft when beating to windward and a larger bending moment downwind which is taken by the sideways shape of the spar as the rig is turned through 90 degrees for the running conditions. At deck level the shape needs to be twice as strong sideways as fore and aft, whilst at mid height the stiffness is equal and the mast can be circular. Towards the top the masts needs to be stiffer fore and aft than sideways.

If the engineering is correct a non technical sailor (and they are generally the fastest ones!) will look at the mast whilst racing and say it bends in a nice curve, This 'nice curve' has a constant radius - it is part of a circle and it means that the sailmaker can plan for a regular luff curve. It is a happy coincidence that the ideal engineering mast happens to bend with constant radius of curvature which is also ideal for sail control. It must be remembered that the chord of the sail varies from zero at the top to a maximum at the boom and this means that as the mast bends the sail fullness is progressively flattened from the top down towards the boom. It is therefore possible for a mast that bends in a constant radius of curvature to have one sail that works well in a wide range of wind speeds.

The Finn rig looks simple and elegant but is in fact a much more sophisticated aerodynamic arrangement than the conventional classes that have a mass of wires holding and controlling the mast.

Mast Choice
When looking at a Needlespar aluminium mast, there are two major factors to consider: top colour and joint height. There are three top colours available: blue, red, and black. Sometimes they are classified as:- Blue: bendy; Red: stiffer; Black: average. Black tops seem to be favoured as the faster masts. The mast stiffness is actually determined from the height of the first joint in the mast - the higher the joint, the stiffer the mast. This is measured from the top of the lower black band to the joint. A 2800 mm joint is recommended for lightweight helms, 3100 mm for the heavyweights, with the average height being 3000 mm on a blue top. Fast Finn masts seem to vary from 2840 mm up to 2920 mm, mainly being black tops.

Booms should be as light as possible. Sideways bend should be avoided at all costs - it makes leech control in the lower third of the sail very difficult.

Fast Finn Masts
The general rule is that if there is more flexibility fore and aft, there is more sideways flexibility and this impairs pointing ability. However, if a stiff mast (ie long bottom section) is used then the helmsman's weight must be appropriate to prevent early overpowering, therefore the higher the crew weight the higher the joint height. Whatever type you use, the bend both sideways and fore and aft should be measured under conditions specified by your sailmaker in order to match up bend and sail luff curve. If these are not compatible, then you can expect very little success in your racing. Carbon masts should bend in the same manner as the alloy ones, except that they straighten up after bending about four times quicker. This allows for better fanning of the sail upwind. With a new mast go sailing in all conditions with the same sail as before so as to eliminate the variables and decide if it is actually any quicker! The critically important end result is to end up with one sail and one mast so that life is easy and you can concentrate on tactics and boat handling rather than gear. At major important regattas there is simply not time to re-rig masts as it is better to get away and eat/sleep! For the record, the two famous masts - 'Pinky' and 'Perky' that Stuart Childerley used during the 1988 campaign until they got sliced up in Kingston, Canada were Needlespar black top 2.85 and 2.9 metre joint heights.

Mast Rake
To get the best out of your Finn a different setting of, say, mast rake may be required for different wind strengths, although most mid-fleet sailors tend to leave this alone to one all round setting. However, what may be fast in light winds may be a bit of a handful in strong winds so some compromise is usually necessary. Finns are relatively easy to tune roughly because the amount of tolerance that you have to play with is relatively small. There are generally recognised mast rake measurements that can be used and until recently the fore and aft position of the mast at deck level was fixed within a small tolerance.

Mast rake is measured by hoisting a tape measure on the halyard and measuring from the top of the mast down to the centre of the transom. A good starting point for mast rake is 22'4" (6800 mm), but depending upon your sail and mast may have to be slightly forward or aft of this position. When the wind increases the mast can be raked forward so that the sail can be flattened more. Because raking the mast forward increases the distance between the deck and the mast tip, greater tension can be created in the leach, thereby increasing mast bend and making for a flatter sail.

These are just guidelines, intended as a starting point and no more. What is useful is an idea of how changing the rake will effect the handling of the boat, or rather, more usefully, how to change the handling characteristics of the boat from one you don't want to one that you do want.

Weather Helm

The Centre of Effort of the rig must work in conjunction with the Centre of Lateral Resistance of the hull and foils to produce boat speed. If the C of E is forward of the CLR the boat will display lee helm. If the C of E is aft of the CLR then the boat will display weather helm. The CLR is basically fixed (unless you want to move the centreboard bolt and you can’t move that very far) apart from lifting the centreboard up, in which case the CLR will move aft. However in most cases you will want the centreboard at its maximum drop to reduce leeway. Thus to shift the forces you need to shift the rig. Note, that this fine tuning is a useless procedure if you don’t set the sail up correctly. A badly set sail can induce far more weather helm than any incorrectly raked mast ever would and this should be your primary concern in the first instance.

Increase weather helm by:

• raking mast aft
• moving mast aft
• moving centreboard forward (or dropping it)
• moving draft in sail aft (ease inhaul, outhaul, cunningham etc.)

• raking mast forward
• moving mast forward
• moving centreboard aft (or raising it)
• moving draft in sail forward (tension inhaul, outhaul, cunningham etc.)

Thus weather helm can be induced by moving the Centre of Effort aft, or by moving the Centre of Lateral Resistance forwards and decreased by moving the Centre of Effort forwards or by moving the Centre of Lateral Resistance aft.

Measuring Mast Bend
Going a step further on from the very good, average mast for the light / medium / heavy body weight which, with everything else being equal gets you up there, the next step is a deliberate and careful process to find a slight edge to get you right at the top position in a major international regatta. Remembering that you race downwind as well as upwind, measure different masts to find the one that seems to be like the one required just for you. Taking the good mast that suits your weight as the control, measure its bend characteristics as shown.

It is also important, once a fast mast has been found that it is accurately measured so that if it does get broken, another mast can be found with similar bend characteristics without extensive on the water testing. It doesn't really matter how you do it, so long as you use the same method for all your masts. However some sailmakers will specify a certain methodology in order to be able to accurately cut the sail luff to match your mast bend.

Basically the mast is supported at two points along its length and a weight is hung from the mid point. A line is tensioned between either ends of the mast and measurements are taken between the now curved mast and the line. These measurements define the bend characteristics of the mast. Measurements are taken at quarter or eighth intervals along the mast. To measure fore and aft bend characteristics place the mast on its forward face and measure from the line to the aft face of the mast (the back of the track) Then to measure the sideways bend characteristics place the mast on its side and measure from the line to the centre of the mast track. The mast is supported at the tip and also at the step or the  gooseneck. The weight should obviously be heavy enough to bend the mast enough to take meaningful measurements - 15 - 20 kg is common.
 

Sails

Having found a mast, you then need a sail to fit it. Take a sail, hoist it up the mast, stretch it out to the black bands and tension the tack a touch. Pull the boom down to the deck and observe the luff. If the sail is loose and baggy in places then it means that the mast is too stiff or that there is too much luff curve (too much cloth). If there are patches of excess tension emanating from the luff seam then the sail has not got enough luff curve (not enough cloth) for that part of the sail or that the mast is too bendy. Change the sail, change the mast or have the sail recut.

The unstayed mast bends increasingly through increasing wind strengths with the sail cut to accommodate the change. To achieve this, not only must the sails have a luff round cut to match that of the mast but the cloth must have sufficient stretch across its bias in order to accommodate these changes in bend. Broad seam shaping is also important, and the luff round/broad seaming ratio of a sail is controlled by the sailmaker in a similar way to that of other classes. The bias stretch characteristic of unstayed rigs makes the cloth selection of paramount importance. Too stiff a cloth and the material will only be of optimum shape for one mast bend, too much stretch and then problems occur with the flow moving from one area of the sail to another in differing wind strengths.

Luff Curves
Always an area for great debate. Follow the instructions after having run in the sail gently for four hours in force 3-4 and a good force 5 for an hour then test it. Then take advice if you are unsure before altering it. (The position of the headboard and headboard slug relative to the luff rope is a common problem in a sail that does not fit.) Basically the luff curve should be even along its length and flatten off at the top of the sail first when in de-powered mode.

Fitting Out

Fitting out a Finn is a very simple process compared with some other dinghies, however there are a few important rules that must be followed. The end result should be a free flowing system that works well on all points of sailing with easily operated and accessible cleating positions. Enough thought applied to the position and fixing of fittings can be amply rewarded when out on the race course. Compare the helm who struggles with badly fitted control lines up the last beat in a force 4-5 when the last thing he feels like doing is struggling, with the helm who can almost effortlessly de-power the sail with the flick of a finger. Properly fitted boats therefore can not only save time but also reduce unnecessarily wasted effort. Imperfectly aligned systems can to a certain extent be made to function better by using the most friction free and probably the most expensive fittings that you can find. It is far better though to have correctly fitted systems that work because they were designed to work rather made to work in spite of a bad design.

The diagrams on the following pages are based on the standard Vanguard type layout. However because all Finns are basically similar, the same systems can be used on any hull with perhaps only a few minor modifications. Most of the diagrams are self explanatory. At the end of this section the BFA Rigging Sheet 1 and Sheet 2 are reproduced. These show a lot of detail and are clearly annotated. They are based on the hull design on the Taylor all-glass hulls.

Fittings
When choosing fittings it is usually best to choose large diameter ball blocks rather than the frequently recommended micro blocks. This may seem strange but the larger block provides a much better grip on the rope as well as positioning and guiding the control lines much more accurately. Two choices of cleat can be considered, either one with moving parts or one with no moving parts. As a general rule buy the best that you can afford in either category. Money saved here is not really saved at all because as you will find out, your plastic one piece cleats will wear down quickly causing the lines to slip, and the inexpensive moving parts cleat will cease to function correctly. A little extra wise expense at the fitting out stage can save expensive replacements after a season or two when all the cheaper fittings have worn out.

Control Lines
The control lines are led from the cockpit area down to a doubling block below the foredeck and then to the base of the mast and up through the mast deck ring. The positioning of each control line through the deck ring is important. The outhaul and kicker lines must be led through the two more central holes in the deck ring because these control lines have to be aligned to the boom. If the lines are not on or near the centreline, then they will be at an angle as they approach to the blocks on the boom and cause extra friction on the system components and chafe on the lines. Cunningham and inhaul controls lines are mast aligned and their athwartships position is therefore not as critical. As far as the order of the cleats on the sidedeck is concerned, the only criteria is that the kicker should be the most aft. The other three are mainly adjusted when hiked on a beat whilst the kicker is mainly adjusted when sailing offwind and sitting further aft. Therefore it is sensible to put the kicker cleat as far aft as possible in order to be able to reach it with ease when sitting at the back of the cockpit.

Some Finns will have continuous control line systems - that is a continuous loop of rope through the blocks and both sidedeck cleats. Whilst this method has the advantage that you will never run out of rope to release (for example - the kicker at the gybe mark), problems are caused if you forget to cleat the line before a tack/gybe. There is nothing wrong with non-continuous lines - if anything they allow for a neater cockpit, but they do require some forethought before a tack/gybe to ensure that there is enough slack on either side of the boat to operate that control after the tack/gybe has taken place. Also you have to ensure that the ends do not get washed down the self bailers by either tying large knots in them or by using plastic balls on the loose ends.

Centreboard
As well as an uphaul led aft to the sidedeck, the centreboard needs an elastic shock cord downhaul to hold it in place in case of a capsize. This downhaul keeps the centreboard up/extended when the boat is inverted. Lead the shock cord aft and through a turning block and then round the front of the centreboard case and up the other side to another turning block and then back to the centreboard arm. Put a hook on one end of the elastic so that the tension in it can be released when the boat is ashore and so lengthen the life of the shock cord. Some Finns will have the centreboard uphaul led to the underside of the traveller thwart and some will be led to the sidedecks. The key element is to be able to work with what you have - and if not to change it.

Traveller
The traveller control should be a 2:1 system with the dead end tied to a hole made in the middle of the thwart - this cuts down on superfluous rope. This is possible because there will never be a need to pull the traveller to windward. An optional extra (although once it has been used you will not want to  take it off), is to run some thin elastic shock cord from one traveller line through a block in the bow to the other traveller line. It is attached to the traveller line by either a small block or ring. This ensures that when the traveller car passes along the track the unused control lines do not get entangled around it - the lines are automatically pulled forward and are then out of the way.

Toestraps
Toestraps should be very firmly bolted into place. They are the only thing holding you and the boat together. Vanguards normally have adjustable runners on tracks fore and aft of the toestraps with an adjustable control line at the front end. On the Taylor hulls, the toestraps are normally bolted through the knees at the cockpit edge. Adjustable toestraps can be very useful when trying to adjust body position, either to accommodate or ease pain or to hike further out/in or to hike higher out of the waves. Again, once the flexibility of adjustable straps is experienced,you will not want to return to fixed ones.

Toestraps should be wide, padded and stiff. The straps on either side of the boat should be tied together with shock cord at the front end so that they are pulled together and away from the deck when the adjustable line is released.

Mainsheet
The floor block must be a ratchet block. The blocks on the boom and traveller must be of the non-twist sort otherwise they will turn and you will end up with a twisted mainsheet offwind that cannot be played due to the friction created. Also it is imperative to correctly position the loops or hangers on the boom. Their distance apart should be the same as the diameter of the traveller block and directly above it. If they are anywhere but on either side of the traveller block, an uneven force is exerted on the boom, pushing or pulling along its length rather than just downwards as should be the case. If the loops are too far apart then purchase power is lost when sheeting in hard.

Mast
The step and the gate should be tight fitting so as to reduce mast 'wobble' which can slow the boat down in light airs. The maximum allowable play is 5mm. This is sometimes used to advantage by allowing the mast to move forward when sailing offwind, while bringing the mast aft when sailing upwind. The boom should also be a tight fit in the gooseneck, again to reduce play. Use a bolt if necessary to ensure that the gooseneck jaws firmly grip the boom.

A retention pin should be fitted to the heel of the mast to stop the mast coming out of the step during a capsize, which could lead to the loss of the foredeck. An alternative method is to bolt a device onto the deck which is bolted into place over the deck ring, but not touching it.

Rudder
Again this should be tight fitting with the minimum of play. This is essential to maintain total control when steering aggressively. A boat with a wobbly rudder assembly will not react as quickly as one with a snug fitting rudder. Time and distance is lost while the rudder takes up the slack before moving. Put both pintles on the transom with the bottom pintle longer than the upper one so that the rudder is easy to locate when launching. Also, having both pintles on the hull means that the rudder can be shipped on the top pintle only which may be useful in the case of a difficult launch. For a retaining clip only ever use the stainless steel ones. These are far superior. Fix it to the hull with one bolt. It can then be swivelled to one side when unshipping the rudder, so that you don't have to depress it when coming ashore, just turn it to one side. These little things can make life much easier and doing this can also save the leading edge of your rudder because of the ease and speed of unshipping if the ground comes up quicker than you anticipated.

The tiller should be firmly fixed to the rudder stock. Some Finns will have a lifting tiller but this is down to choice. Use whatever you feel comfortable with. The tiller extension joint should be of the plastic type allowing complete freedom of movement and eliminating the possibility of a 'lock-up' when tacking.

Sidedeck Pads
These are an essential to aid comfortable hiking. All Finns will have them fitted and some thought should be given to this because your entire sailing effort will be directed through the pads. If you are not comfortable you will not be able to function properly. Pay attention to the padding on the inside edge so that it can support the legs under the toestraps.

JC Strap
A JC Strap made of strong elastic shock cord runs from one side of the boom to a block on the bow and back to the other side of the boom. In light airs the tension in the elastic holds the boom out on a reach and run and stops it from swinging in towards the centreline when there is not enough wind to keep the sail filled.

A control line system and any fitting is only good enough if you are happy using it and can get along with it. If you can't, then something has to be done to remedy the matter. Make sure that all lines can be reached with ease from wherever you would be sitting. Ensure that fittings are not going to be in the way of ropes or any part of you. Plan ahead in a fitting out process so that everything is logical and will function accordingly. Most of all use gear that you can trust not to fail when you need it most. To get the most out of them, Finns need to be pushed hard and gear failure should never be an excuse for not finishing a race. Make sure that whatever fittings and rope you finally decide on, they will not break in a windy race or fail to work effectively when used to the limit. If you are confident that the boat will stand up to the extremes of the weather, then in anything less than the extremes, you can push the boat as hard as you like without worrying about gear failure and damage.
 

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