Introduction

Building the St Ayles Skiff kit – Ch 1 – Introduction

(reproduced courtesy of Jordan Boats)

The kit for the St Ayles Skiff has been designed to make it as easy as is reasonably
possible to build. However, it is not something that can be done in a few days or
weeks. The builds completed so far have taken anything between two months by
two retired professional boatbuilders working more or less full time to seven
months taken by a group with no boat building experience working evenings and
weekends only.

It is intended that the boat builders will try different things. Once the hull
planking and gunwales are complete, you are encouraged to use your imagination and skills to try different layouts in the boat, and it is not expected that you will
follow the construction drawing in every detail.

Talk to other groups who have built the skiffs, go and see their boats if possible,
look at photos, and find out what is thought to be the current best practice. Some
Groups have recorded their build on the Web, this can be a useful reference if you
get stuck.

Materials

Use the best materials that you can reasonably afford. While the ethos of the
project is that the boats are built at a very low cost, there are some areas where
you should not skimp. You will want the boat to last for many years, and the initial
choice of materials will impact on its longevity.

Timber

In general, it is recommended that larch is used for nearly all of the timber
work, except where there will be considerable wear – mainly around the
oarlocks. For these areas, the hardest hardwood you can find should be
used.

The timber needs to be of a good quality, and knots should be avoided. The
timber list tells you where knots are acceptable.

Douglas Fir is a good substitute for Larch, though a little denser. It is also
stiffer, and is good for the oars.

Glues

Use good quality Marine Glues. For most of the work, you should use epoxy
resin, thickened as necessary to fill gaps. For certain tasks, notably
laminating the stems and fixing the gunwales, you may use marine
polyurethane glue. This can be used where there are no gaps to fill and the
timber has a relatively high moisture content. PU glues have poor gapfilling
qualities.

Paints

Marine Paints (as anything with “Marine” in the name) are expensive, and
you will need a considerable amount of it. It will probably be one of the
most expensive single items after the kit. However, a good paint system,
applied as per the manufacturers instructions, will last for many years, and
protect the boat from the elements.

We do not recommend two-pack paint as there is a certain amount of
flexing in the hull in use which is likely to crack the paint surface.
Fixings & fittings

All fixings left in the boat after completion should be marine standard,
either A4/316 stainless steel or silicon bronze. Do not be tempted to use
stainless steel screws from your local DIY store as these are generally
manufactured to a much lower corrosion resistance. Likewise, brass screws
corrode quite quickly and lose strength in seawater. Temporary screws used
to hold parts together while the glue sets and then removed may be any
available, but they MUST be removed and the holes filled before finishing.

Where to build?

The skiffs have already been built in many different kinds of places, from cowsheds
to industrial units, and in one case, actually in a boatyard!

The absolute minimum area you should be thinking about is 25ft long and 10ft
wide. Working in an area this small will be very uncomfortable and will only be
possible if there are full doors so that long pieces can be taken outside to be swung
around if necessary. Nearly all preparatory work will have to take place in another
area.

The ideal minimum will be approximately 30ft by 20ft. If this is what you can find,
you will want to position your building frame to one side so that there will be about
30″ from the building frame to the wall. This will give sufficient space to work in,
and leave a larger area to work on the other side of the boat.

The workspace needs to be well lit, and preferably have a power supply for the
power tools.

Tools

You will not need a huge array of tools to build the boat, and most of them can be
found in a keen DIYer’s tool box.

This list is not exhaustive, but covers the main tools required or desirable.

First Aid kit

The most common injuries that are likely to happen are small cuts from
tools and handling wood. Make sure that you have a good supply of
plasters.

There will also be many times when splinters need to be removed, so
include a good pair of tweezers.

You should also keep larger wound dressings in case a more serious accident
occurs. Take advice on the contents of the kit if necessary.

Craft Knife

These will always be useful for trimming, carving etc. Make sure you use
one with a retractable blade as this is probably the most dangerous tool in
the box.

Planes

Block planes are the most heavily used. For preference, you should use one
with screw adjustment which allows you to make the fine changes required.

The cheaper ones with a top screw adjustment are difficult to set to the
right cut.

You may want to purchase a Rebate plane for cutting the gains or geralds in
the planking, but they are expensive and the job can be done quite
adequately with chisels.

Chisels

Use a good set, and keep them sharp.

Sharpening Stones

A very important investment to keep the tools sharp and safe. Diamond
sharpening stones are recommended. Learn how to use them properly;
sharper tools are safer tools.

Saws

You will need a rip saw for rough cutting, and a good fine toothed saw for
the fine detail cuts. Japanese Pull Saws are now very popular, and the
replacement blades are not expensive.

Drill

A battery drill is necessary, and especially useful with a screwdriver bit.

Sanders

Electric Sanders are very useful, but be very careful with belt sanders.
These are very aggressive and can strip the outer veneer off plywood in
seconds. Random Orbital Sanders are a lot safer to use in this respect, and
are easier to control.

Electric Planers

Worth having, but not worth paying for specially. They are also very
aggressive, and should be used with extreme care. Unless you are an expert
with them, use them for doing stock removal on the hog, but finish the job
with the hand planes to get it right.

Hot Air gun and Scrapers

When it comes to cleaning up the hull, the best method of removing excess
epoxy is a hot air gun and scrapers. More detail in the chapter regarding
this stage – beware of scorching the timber!

Jigsaw

Always useful for cutting out the planks and rough shaping.
The big power tools that can be invaluable. When it comes to these power tools, it
is best to make sure that you have a joiner or carpenter who has these tools on the
building team.

Bandsaw

Table or Circular Saw & Planer Thicknesser

These two tools if available will save a huge amount of money in preparing
the timbers required for building the boat. With these, you can buy in
boards and cut them to the required size, rather than having to pay
someone else to cut and dress them to size.

Some general notes about the build…

Most of the time, only a limited number of people can actually be involved “on
the boat”. For instance, when planking, 3 people is probably about the
optimum – with 4, one is going to start getting in the way. Fortunately, the bit
which needs the most hands to get an unpleasant job done quickly can have the
most involvement – scraping and sanding!

Think ahead – what is going to be required later, and you can get other people
involved – kabes, thwarts, rudder, and especially the oars. In some of these
cases, measurements can be taken off the boat and the work done elsewhere if
the building space is restricted.

Almost all operations in building the boat are more easily done on a flat
surface, e.g. gluing up the frames. If it can be done away from trying to do
things in three dimensions, do so. Anything that has occurred to me that can
be done in this manner will be flagged up in the Build Instructions as we come
to it.

A Short Primer on using Epoxy Resin

This is by no means definitive, and you should read and understand the Safety and
Usage guides supplied with your epoxy. If they are not supplied with the package,
insist that your supplier sends them on.

Epoxy Resin Glue is the magic ingredient in making the St Ayles Skiff buildable by
amateurs. It is incredibly strong, it is fairly easy to use, and it is great for filling
the gaps when your joinery skills are not quite up to the mark. Even better, when
it sets, it does not shrink or expand, so when you pack it into the gap and leave it
to set overnight, the gap will stay filled when you come back in the morning.

However . . .

Epoxy resin can be dangerous; many people become easily sensitized after only a
few exposures. Always wear gloves (preferably nitrile rather than latex) when
handling wet epoxy and avoid any skin contact. Provide good ventilation. Always
wear a good dust mask when sanding. Epoxy that is hard (less than 48 hour old),
but not fully cured (up to 5 days old) is especially dangerous to breathe. Read and
understand the Safety Leaflets included with your epoxy.

Epoxy resin is supplied as two components – the resin and the hardener. Different
brands of epoxy are mixed in different ratios, and it is strongly recommended that
you stick to one brand the whole way through your build so that there is no
confusion.

It is normally supplied with pumps that will supposedly dispense the fluid in the
correct ratio. However, pumps can malfunction. I therefore recommend that
mixing is done by weight which is more reliable. An electronic scale will cost a
little money, but will guarantee that you mix the correct quantities (providing that
your arithmetic is right!). Using a scale also means that when necessary, you can
mix smaller quantities than the pumps will dispense, therefore saving epoxy.
Epoxy is expensive, so waste is undesirable. When you are started learning how to
use it, mix smaller amounts than larger – you can always make up another pot – but
you cannot put unused epoxy back in the can! Use any excess to fill in gaps from
earlier operations.

To be fully effective, the epoxy will almost always need some kind of additive to
help it do the job intended. There are three main additives that you will require:

Microfibres. These are a general purpose gluing additive – tiny fibres that
mixed together increase the strength of the cured epoxy.

Filleting blend. These are used to run fillets between parts at angles to
increase the strength of the joint, e.g. between the frames and the
planking. It is also good for forcing into the small gaps which are most
likely to happen when gluing the garboard to the hog.

Fairing compound. Used to fill in gaps where there is no structural
strength required – probably will be used much more later when your boat
will gather the odd dent or two in use. The fairing compound is much easier
to sand than a pure microfibre mix.

Epoxy requires a certain amount of warmth to set properly. The warmer the
ambient temperature, the quicker the epoxy will cure. As a general rule, do not
try to glue if the temperature in the workshop is below 5C. Read the instruction
leaflets for the brand of epoxy that you are using as the minimum temperature
varies. Local heating can be used with care.

If in doubt, leave the mixing pots out overnight and check on your following work
session that the pots have cured properly.

Hardener is usually obtainable as “Standard” or “Fast”. If you are working in an
unheated shed in winter, it may be advisable to use the fast hardener. When the
weather warms up, you will want to revert to the standard or slow hardener.

Some brands of epoxy, when curing, will exude a slightly greasy feeling compound
known as Amine Blush. This is particularly evident when curing at low
temperatures. When this occurs, the amine blush must be removed by washing
with slightly soapy water, the material allowed to dry, then sanded with fine grit
paper before more epoxy can be applied.

The epoxy curing process is exothermic – it gives off heat as the resin & hardener
react. This heat will further increase the speed of the reaction, and it is therefore
important that when mixing large quantities of epoxy a large pot is used and that it
is applied as quickly as possible. If your epoxy starts its self-sustaining reaction,
get it outside and preferably into a bucket of water as quickly as possible. This is
not a regular occurrence in the middle of a Scottish winter! Try not to hold the
mixing pot in a full hand grip as the warmth from your hand will also speed up the
reaction.

Stir the resin and hardener for at least two minutes before adding any additives.
Before applying any epoxy to glue parts, it is necessary to wet out the areas to be
glued. This is especially important when gluing end-grain on the plywood, which is
very porous.

When epoxy is applied to wood, the porosity of the wood will soak some of the
epoxy into its fibres, particularly on end grain. If the wood is not pre-treated this
way, the epoxy can be absorbed into the end-grain so that there is very little
actually left in the joint.

The epoxy glue is mixed from the resin and hardener at the correct ratio, and
applied to the area to be glued with a cheap brush, cut so that it is short and stiff.
The epoxy is then left for at least half an hour – more in cold temperatures, so that
it will be absorbed by the wood fibre and start curing before the main bonding
epoxy is applied.

Finally, a small warning on a “feature” of using epoxy that I have not seen in any
manual. When epoxy sets, it sets very hard and in some cases where it has run
over plastic protection (when gluing scarph joints) or dripped (like a stalactite),
the edges and points can be extremely sharp. When inspecting joints after epoxy
has set, be very careful and sand or plane any of these sharp projections as soon as
possible to keep a safe working environment.

 

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