[Richard O'Clery]

If the model is 1/18 scale, it is one eighteenth of the size of the original car. Ie any measurement taken from the model will need to be multiplied 18 times and you have the size of the original - in theory. Any errors in the scale model will be multiplied 18 times too. If you have some known dimensions of the original car (ie wheelbase, track etc) you can help remove some dimensional errors from the scale model, but it will be hard to remove errors from the actual shape of the body. That said, scale models made from the blueprints of the original car maker can be pretty accurate.

When the computer draws the 3D image from the digitised model, you can tell it to multiply all dimensions by 18.

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