This section is from the book "Spons' Mechanics' Own Book: A Manual For Handicraftsmen And Amateurs", by Edward Spon. Also available from Amazon: Spons' Mechanics' Own Book.
This variety of work, as its name implies, is used for all purposes where outline shaping alone is required, either applied separately or to work that is to be afterwards carved. The importance of getting all carved work previously shaped by fret-cutting, so far as is possible with the nature of the design, is much greater in some cases than in others; but in all it is sufficient to demand careful consideration. It is advisable to first make a pattern the requisite shape, and to mark out from it. It should not be very thick; about 1/8 in. or 1/8 full will answer best. By placing this upon your wood you will be able to mark out in the best manner. If your work is straight or nearly so, there is not much difficulty; but if it curves considerably, as in some kinds of legs, cabriole, for instance, endeavour to arrange the markings so that they will to a great extent cut out of each other, getting the hollow portion of one against the rounded of another, and vice versa.