The Stem of a
wooden Boat must be regarded as
being part of her backbone.
It is often one of the first areas to need repair as it is
vulnerable to rot and damage from collisions and groundings.
However, many of the necessary repairs are well within the scope of the
There are several different methods of
building a stem.
They can be made in one piece, either sawn from a crook or steam bent.
Others are built up, either by laminating or the traditional method of
several pieces together.
All of them are susceptible to end-grain rot.
Rot at the top, where it pokes up above the deck is relatively minor
Rot at the bottom end is more serious.
The fore peak is an area where ventilation is poor at the best of times
often made worse by being enclosed with lockers, such as the chain
corrosion can affect all forms, especially where the stem meets the
The type of stem which is built from bolted sections is particularly
to fastening corrosion which, can lead to the seams opening.
On older boats iron bolts have been used, these may have worked rather
during their lifetime unfortunately, their life time is fairly
Initially as the joint ‘works’ and increases in size, water
penetrates along the bolts causing them to rust, the rust expands
hole until it widens some more, then more expanding rust refills the
until there isn’t enough sound metal left.
This type of construction can also suffer from opening joints as a
the wood being allowed to shrink too often when it dries out.
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One of the major problems I
had to resolve when I
began work on Mignonne
damage to her stem.
The damage had probably been
compounded by the amount of
time she had been out of the water allowing the wood to shrink.
Fresh rainwater had rotted the
top end as well as
accelerating the corrosion of the original iron bolts holding the
The pressure from the
expanding rust on the bolts had
split the dry wood of the knee and had begun to split the ends of the
Before I attempted to do
anything with the stem I had
replaced all the frames which were damaged so the planks would be
I had also raked out what
remained of the old
I could then start to look at
The knee had split along its
length, so it was easy to
finish off the split with a chisel and remove the two halves.
What remained of the exposed
bolts was chopped off and
the ends driven out of the stem with a drift.
The next job was to open the
hood ends (plank ends).
The planks had been fastened
with copper nails, to
release these I carefully drilled off the heads.
Then using wedges and shores I
carefully pried the hood
ends apart in the area of the damage, taking care not to damage the
Fortunately none of the frames
had been boxed in and the
planking held its shape well enough not to need any support.
Before I removed any of the
stem I took a rough pattern
from the original.
The next job was to cut away
the wood close to split so I
could see the extent of damage, then I cut away some more until I
Then, when I discovered that
the splits were not too long
I scarfed the ends. This was rather difficult to do with the saw, due
limited access so, some of it had to be done by chisel.
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Having cut out
the damage I now took
another template of the gap and scarfs using stiff card.
Then having planed the replacement
timber to the width of
the original I used the two templates to mark out the new shape.
This I cut out over sized.
Any subsequent adjustments to
size and shape were going
to have to be made to the new piece due to the lack of space between
From there on it was a case of
holding the new piece to
the gap marking trimming and trying again until the scarfs fitted.
Once I was happy with the new
piece I propped it in place
and took a template of the inside surface to cut the replacement knee
The knee was made from the
same width timber as the stem
When I was satisfied with the
fit, both pieces were
propped and wedged in place and the holes for the through bolts
Bolted together with the new
silicon bronze bolts and
having checked and fared all the joints I then released the hood ends
marked the rabbet line, making sure that it coincided with the existing
With the new piece out
again, I fared the line with
a bendy batten.
Then, I chiseled out the
rabbet, constantly checking that
the angles were correct to take the plank ends.
Either end of the rabbet was
left rough for final faring
to the old when bolted in place.
When I was eventually happy
with the fit I cut the outer
shape using the original template.
The final faring was done when
it was all bolted in
Due to the lack of space the stopwaters
outside the rabbet line.
Finally, everything was soaked
in creosote, the scarfs
and stopwaters were bedded with a bedding compound and the whole bolted
The hood ends were screwed
back in place using screws one
size larger than original nail holes.
I also replaced all the other
hood end fastenings with
The final caulking
was left until I had
replaced the damaged planks when I re-caulked the whole hull.
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The rot in the top of
Mignonne’s stem fortunately
did not extend below any fastenings so it was a
simple job to cut back to sound wood and scarf it.
Fortunately I had a piece of
timber left over from the
lower repair which was quickly planed to size the scarfed to fit.
The next problem was how to
shape the top.
Having enough timber to play
with I carved the top in the
shape of a seahorse figurehead.
Other minor repairs such as
dents and chips can be
repaired by graving in replacement pieces, sometimes refered to as
Minor leaks can be stopped by
replacing or fitting
And re-caulking or even
caulking along the joints might
be sufficient to stop leaks in the short term.
All of these repairs are
within the scope of the
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