Part 3 - Making the Model
Part 2 - Making
Part 1 - Then
In the last two articles, I’ve covered what half hulls are
and how to make plans for one from pictures of your boat. With
the help of last issue’s article, I will now cover how to
make a model from the plans you drew up. You DID make the plans,
There are two ways for the average boat owner to make their half
hull model, either from a solid block of wood or built up from
ribs and stringers and then planked. Each has its advantages and
I’ll cover them both. Note: I chose to make the model in
these illustrations using the built up style.
The first step, no matter which method you chose, is to prepare
templates. These can be traced from your plans by using carbon
paper. I got a real surprise when I went to the office supply
store to buy some carbon paper. It seems, in this age of NCR paper
and computers, to be a rare thing. The only package I could find
had a hundred sheets and was expensive, but I did find more reasonable
quantities and prices at the local craft store. I used regular
poster board for the templates themselves.
You are going to need a template of the side (or profile) view
of the boat as well as templates for all the stations or cross-sections
on the plan. If you are making a block model, these section templates
will be cut out of a poster board square a couple of inches larger
than the section.
||If you are making a block model, these section
templates will be cut out of a poster board square a couple
of inches larger than the section.
||For a built up model, these section templates
will be the shape of the section itself
The size of the section templates for the built up model will
need to be smaller than the drawing size by the thickness of the
backbone and the planking.
Finally, if making a block model, you will also need a template
for the top or plan view of the hull. Mark all the templates with
the appropriate station and centerlines. Now let’s get on
to the models themselves.
Most original models were built from blocks of wood. Those blocks
could be solid chunks of wood or blocks glued up from individual
layers. If you’re planning on using this method, select
good straight-grained woods. Basswood is good as are mahogany
or pine. My all-time favorite carving wood is sugar pine, but
that’s getting hard to find and expensive. Avoid curly grain
or knotty wood as it makes smooth carving difficult.
Basswood carving blocks or a variety of different thicknesses
of wood can be ordered online from several sources (try: www.woodnshop.com
or www.rockler.com). Prices
are a little higher than local stores, but availability and quality
are usually better.
The layers of wood can be glued and clamped together with any
good carpenters glue and then left until the glue is completely
dry. Smooth up the surfaces of the block and draw the station
lines on it. Trace the top outline and the side outline onto the
block. The quickest way to proceed is to cut the block along these
lines with a bandsaw. If you don’t have one, you can try
a coping saw or saber saw with a long blade.
Cut the top outline first and then tape the cut-off piece back
on with masking tape. This will allow the block to sit level on
the bandsaw to cut the side outline. Once these two cuts are made,
retrace the station lines around the block. You can now start
carving away the excess wood, testing the shape of the hull with
the templates you previously made.
I use a variety of tools for this kind of carving. A small block
plane, gouges of various sizes, chisels and small drawknives used
in violin making work best for me. I purchased most of these tools
online or at specialty hardware stores. Be sure and keep the cutting
edges as sharp as possible for quick and accurate work. I use
two grades of Arkansas sharpening stones and then polish the cutting
edges with Tripoli compound on a leather strap. One drawback of
this model making method is the need for good woodworking tools.
Keep carving the hull while checking with the templates. Feel
the hull with your fingertips as you carve to keep the lines of
the hull smooth and flowing. Once the block is shaped to the templates,
you can sand the hull and prepare it for finishing. Be sure to
keep the sharp edges of the hull crisp, don’t sand them
round. If you carved it accurately, minimal sanding should be
needed. The hull is then ready for finishing.
I recommend the built-up method if you don’t have access
to a variety of power or carving tools. Simple Exacto knives,
found at any craft store, work fine. I used 1/4” inch hard
balsa wood for the backbone on this model. A short length of 3/4”
square pine was glued on this backbone to reinforce the balsa
and to accept the screws that will mount the model to the backboard.
I cut the stations or frames out of sheet balsa and notched them
to fit around the pine strip. Notches were cut in the top corner
and at the chine line of the stations to accept strips of balsa.
Work went quickly as I was using 5-minute epoxy to glue the parts
||I was using 5-minute epoxy to glue the parts
Once the stations are glued to the backbone and the initial
stringers are in place, it is time to plank the hull. In my case,
the original boat was sheathed in plywood, so it was a simple
matter to use 1/32” plywood for the hull planking. I first
made patterns, using poster board, before cutting the plywood.
I was able to cut and trim the plywood with standard scissors.
If your model has a rounded hull, use smaller strips of balsa
as planking. These can be glued edge to edge as well as to the
stations and will follow the curve of the hull. Once the planking
is finished, sand the hull and fill any imperfections with wood
By now, either model is ready for the final steps. If your boat
has spray rails, skegs, chine runners or gunnel details you wish
to add, now is the time
||If your boat has spray rails, skegs, chine runners
or gunnel details you wish to add, now is the time.
On my model, I used square strips of basswood for these details.
Rubber bands and pins were used to hold these in place. Crazy
Glue or CA (cyanoacrylate) glue works well here.
The final finish is up to you. The model can be painted to match
the real boat or finished natural. I used spray enamel from the
local home improvement store to finish the hull. The boot stripe
is a narrow roll of boot stripe tape from the local boat store.
The last part of the model is the backboard. There are a multitude
of woods to choose from. Mahogany, cherry or oak are great for
backboards that are finished natural. Poplar or pine is fine if
you want to paint the backboard. Allow several inches of backboard
all around the model so it doesn’t appear crowded. The edges
of the board can be left square, chamfered or, as I did, routed
with a fancy bit in a router.
||The edges of the board can be left square, chamfered
or, as I did, routed with a fancy bit in a router.
The model is then screwed to the backboard. Make sure the model
sits as it would on the water, with its waterline parallel to
the edge of the board. The last touch is an engraved brass plaque
with the boat’s name or model on it. You can have these
made at one of the engraving kiosks at the local mall.
Well there you have it.
||Well there you have it.
Making a representative half hull model of your boat isn’t
difficult. I hope these articles are enough to encourage you to
make your own model. Sign and date the back of yours, you never
know when you may become a famous half hull maker!
Freelance Boating Writer
Capt'n Pauley's Place
The Virtual Boatyard