I am building a solid hull ship; the kit comes with paper cut-out templates to check the hull shape.

Will these paper templates suffice to check out the shape or is it intended that one should use the templates to cut out balsa templates?

Typically, the paper templates are too flimsy to use to accurately verify the shape of the hull. It is better to copy their pattern to a stiffer cardboard or poster board. You can also use these patterns to make a stand to keep your model in while you work on it, and also to make a nice permanent stand for the finished model.

Ideally, getting a copy of the original ships plans, and creating patterns from the ships lines is the best. Many people abandon the solid hull that came with the kit, and create their own plank-on-frame/plank-on-bulkhead hull (deviating from the kit in an attempt to create a more accurate/appealing model is quite a common practice among ship modelers).
{Monica Chaban}

I usually mount paper templates on some sort of card stock, adding stripwood as needed to stiffen the body.
{ Kurt (Seaphoto) }
IMHO stiff white cardboard has the minimal stiffness and durability for hull templates. Mattboard found in art supply shops for matting pictures would be ideal.

You would, for example, fix the printed template patterns to the mattboard with rubber cement (not water-based glue) and cut as close to the line as you dare with a fine fretsaw or power jigsaw, then clean it up with sandpaper to the line. Some hull section diagrams are printed in such a way that you might need the additional step of tracing them with high quality tracing paper (also from your art supply shop) and then cementing the traced pattern onto cardboard.
{Septimus}

...good quality card (file folder stock, etc.) stock (or thin sheet styrene, or even metal, such as stock from aluminum soda cans), and trim that to shape.

A good idea is to block up the hull so the waterline or keel is level, and then cut a "tab" on the pattern so it can sit using the table as a reference plane...that's more work, but it's also more accurate than trying to fit the pattern to the hull at the keel and shear line only.
{John O. Kopf}

Even better for templates is 1/64" thick aircraft ply. The rubber cement and cut-out process is just as described above. It's very
{Clay Feldman}
Regardless, Use something with a bit more stiffness than paper. Even 'shirt cardboard' works. The pointer about adding 'tabs' which would permit setting all to a horizontal waterline is very useful. Try to keep the working edge of the template as thin as possible while retaining the necessary rigidity.
{RAIcorn824}
...The plywood works great as it is strong and stiff. The balsa has a tendency to be soft when pressed against the hull to check on dimensions.
{David Loseke}
If you're transferring the pattern to thin aircraft plywood, make a Xerox, lay it face down on the wood and wipe the back with gasoline or another serious thinner in a rag. (Don't smoke while you're doing this.) The right amount of soaking and pressure will transfer the Xerox powder to the wood.
{Burl Burlingame}
Don't use gasoline for anything except motor fuel. A friend of my sons was burned to death while cleaning dirt bike parts in a can of gasoline. The spark that ignited the vapor was over 20 feet away.

A safer method is to heat transfer it. Place the paper on the wood, with the toner against the wood and iron it with a normal clothes iron, set to a high temp. Hold the iron on for a few seconds, then peel the paper off.

Sometimes this will cause the wood to develop a curve - if you heat only one side of it, so also iron the back side of the wood and it will flatten out.

There are special toners made to transfer easily, but the standard stuff of a copy machine or laser printer works fine.
{Ron Ginger}

Actually, ball-point pen works well too...put your drawing ink-side down onto the wood and iron the ink into it.
{John O. Kopf}
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