This section is from the book "The Manufacture Of Boots And Shoes: Being A Modern Treatise Of All The Processes Of Making And Manufacturing Footgear", by F. Y. Golding. Also available from Amazon: The Manufacture Of Boots And Shoes.
The putting together of the various parts while stitching is termed "fitting." These parts are, where possible, fitted as intended and designed by the pattern-cutter.
The correct fitting together of the various parts of the upper is an important branch of the manufacture of boots and shoes. It may be performed either by tacking with a needle and thread, or by fitting together by means of an adhesive. Some portions of the work are put together directly under the machine, without the use of either methods just alluded to. There are certain preparatory processes to the actual fitting proper, and a large degree of the excellency or otherwise of the fitting depends upon these initiatory processes. The object to be aimed at should be, to unite the parts with such suitable seams that the flexibility of the leather be maintained. To this end, the pieces that overlap should be made to have the effect of one substance. The rigidity of the seam should not be increased with stiff and non-yielding adherents.
The patterns are cut either to fit, part to part on the cutting-board, or allowances have been made by the pattern-maker for the alteration in size and shape consequent upon the alteration of the plane of the material when cutting to the pattern to that occupied when fitting, and the displacement due to substance. The modus operandi of fitting adopted in any particular case will depend, then, which view has been adopted in preparing the pattern.
To clearly understand this difference the student is recommended to try the following experiment: Experiment.-Take a pattern about 11/2 in. by 6 in., and use this to cut some pieces of linen lining, glace Persian, calf-kid, roan, kip, calf, etc. A piece of the cut-out linen should he laid exactly over a piece cut from calf, and the two short sides seamed together, as ab, a'b', in Fig. 184. After seaming they should he bent round as CD, and the displacement of the lining noted. Kepeat with the other substances and compare results. It will be seen that to get the lining to fit the stouter outside piece, it would be necessary to make it smaller. This has been illustrated by Fig. 184, EH, where the part, P, beyond H, shows the amount necessary to be removed to make the lining fit closely to the stouter piece. The experiment will also show how the amount varies with the substance of the two materials used.
The first process in actual work, after counting the parts, etc., is to lay them out and ascertain the way they are cut. If on the flat-paper-pattern method, allowances will have to be made during fitting for the substance of material used. If, however, this has been correctly estimated and allowed for in the pattern, the process of fitting is simplified and cheapened.