Half-Hull Construction step by step

An article by Octávio Oliveira

The third model on the left column, counting top to bottom,
was the choice to show you my method of carving a half hull.
In this case the famous NAN built in 1896 by William Fife.

Bought and restored by an antiquarian of nautical instruments,
Philipp Menhinicke who "discovered it" in 1998…thanks to the Internet!

Coincidence or destiny, this “jewel” had already belonged to his grandfather…

At August of 2001, after more than 100 years of life, being completely renewed,
navigated to Cowes Island to participate in the jubilee of America’ cup.
A prodigious test of resistance and indeed with extraordinary gracefulness
of 19,25 meters length and more than 300 metres of sails…

The job is beginning…

The plans were amplified to get 60 centimetres of model’s length.

Moulds in cardboard

Thickness. Pieces 1 to 4,--- 9 millimetres. The 5^th--- 14,5milimetres.

Without professional tools it is not easy to get these measures for our model,
but the MDF almost can do that as required. It is the most important advantage of this material.

The moulds fixated to mark that contour.

The pieces sawed with 1 or 2 millimetres out of the lines. Larger is corrected easily not the contrary…

It shows the largest half of the deck, 5,4 centimetres.

All pieces sawed. Two 0/5? The reason is easy…it was to get the correct total thickness of the model.

The temporary assemblage, less the rudder, give an idea of our future half model.

The arrows show the adjust to make with a file appropriate to wood.
Please take care with the extremities. They are very weak.

With the starboard geometric plan, I marked the distance
between the longitudinal lines.

Pieces 5/5 of different thickness glued together.

Pieces 1/5, 2/5, 3/5, 4/5 their extremities numbered in black
have on the reverse contour numbered also,
but in red, where the correspondent piece will be glued later.

Applied 3 layers of leisure (dark red) in the reverse of the pieces.
Interval, 24 hours between the layers. You can see the result in following photos.

This and the next four photos show the correct position to glue, piece by piece.

Each time, it is easier to glue only a couple of pieces.

The complete conjunct. To guarantee a good gluing it is necessary 24 hours

Behind half hull (not yet carved) the mould with vertical lines,
those correspond to the position of different contours of transversal plan.

The mould of half of deck

Two moulds are useful for the first adjustments.

This mould on the top allows to cut the contour of deck

One Knife and a little planer are good to improve our work in this time

The transversal plan is divided in the middle.
At the right side the contours of the timbers 1 to 7, starting from the prow,
in yellow cardboard. At the left side, 8 to 14 in rose cardboard.
The colours serve to show only the 2 parts.
One, the prow to the middle, the other the middle to the poop

Words for what?! The photo is very clear.

The tools needed and the deck adjusted.

The grinder and oil serve to sharpen the craft carving tools.
The small screwdriver was sharpen tool to open grooves following the moulds.

Not a special reason to choose the number 8,
perhaps I Think it gives a better image…,
but our carving is beginning.

Alternately I opened grooves in the block.

In sawing, as it is impossible to correct the mistakes with bitumen,
our task it will be a little difficult.
Remember the model will not be painted but varnished!

The wood rasp will improve a lot the work done.

It is time…not for a break… but to glue the piece 05.

It is possible to see the longitudinal lines in the model.

It is time with the mould 15 and a wood rasp adjust the poop.

Later the rudder in MDF of 3milimetre will be glued
on the correct place in piece 05

Now the sealing primer will be used frequently
to obtain the necessary hardness in order to polish the model
starting with sandpaper 80 or 100 and finishing at 600…

First coat …the model is wet…It will be necessary a lot of them.

The contrast of the longitudinal lines after the finishing.

A piece of specialty paper (I chose faia) cut a little larger.
It is adheared to the silhouette of the deck with contact glue.

With small shears the glued paper, is trimmed to the periphery of the halfhull..

With an X- acto knife the previous cut is improved.

With a small parallel rasp for metal, the paper on the deck is perfected.

The model on a small stand with everything that is necessary in this final phase.

In case that we should opt to place the Half-Hull on the wall.
A support hook, must be fabricated and fastened with screws to the backside,
making sure that they do not protrude to the finished or front side.

Our Nan placed on a wall. Notice, low in the keel the small plate with the name.

If our option is to place it on a nicely finished backboard.
We start by making a traced contour in bristol board that later is cut.

Two points on the extremities of the silhouette are shown here.
These will serve to mark the spots on the Half-Hull
where the thickness of the wood will be sufficent, so the attaching screws
will not pierce through to the front side… making unusable our model.

Using the same template, we position it on our finished oak backbord,
marking the spots for the screw holes to mount the halfhull.
The hardware as well as the tools can be seen equally still to use.

Now our model is ready to decorate a place in our house,
being able to be mounted on a wall or on a bookshelf.

The imagination has no limits.
We are able to mount on the halfhull model, the infrastructures, masts,
and other equipment the sail-boat we are creating a replica of, possesses.