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 pattern for this style is not difficult to design, the principal points to be observed being the selection of the correct height of vamp, the width of the tab or latchet, and the shape of the corners. The substance of the material to be cut from the patterns, together with its nature, will demand variations. There are several ways of deciding the height of the vamp. A line may be drawn on the standard from toe to counter-height, and one-third of this from the toe end will locate the position of the vamp. The width of the tab on this plan may be taken as one-third of the joint-line. Another method is to make the width of tab two-fifths of the vamp when made. It should be remembered that the difficulty of the foot entering this kind of boot is great, if due provision be not made for the passing in of the joint of the foot; and this difficulty is increased as the joint-width is greater. This will necessitate not only a correct width of tab, but a correct height of vamp.
If cutting direct to a last, the greatest width of the forepart should be marked on the top of the front. The vamp-height may also be obtained by adding, say, one inch to the joint table of distances given on p. 114, which will give the height when made.
Fig. 138 will illustrate a twofold method of designing a derby, and will also show the cutting out of the vamp. The height of the vamp A is marked. A set-square is laid upon the tracing, so that one edge coincides with A and the toe end of the standard, and when in this position a line is drawn from A to B. This will ensure the tabs being square when made. The corner of the tab 0 is found either by taking, by means of a proportional compass, five-twelfths of A B, or may be fixed by first deciding the length of wing, which may be taken about the instep-line, or by system shown on pp. 132 and 142. Having fixed D, join A D and find the centre E. By drawing a line from S through E, until it meets AB, the position C is found. Complete as shown in Fig. 138.
The shape of the latchet is an important factor. Fig. 139 will show several kinds. A is the style for colliers' or navvies' goods, and modified suits ladies' work. B is the usual derby tab. C is an improvement on B, the corner being slightly rounded to prevent it catching during wear. D is a bad kind of tab, the lacing when worn causing the goods to pucker. Fig. 140 shows the design for a whole-backed colliers.
A goloshed derby is designed upon the same plan, only provision must be made to allow leg or quarter to pass to outside of vamp. If the boot is to be leather lined, due provision should be made for the stiffening to be placed between the outside and lining, because, unless the upper be very stretchy or light, wrinkles would be found in the made-up boot. Caps may be either pointed or straight, the former giving the appearance of a narrow foot, while with the latter it would appear to be wider.
Quarter Patterns are produced from the standard with the addition of underlay ; unless quarter over, a little extra should be given on the front, especially if a buttoned or similar seamed quarter, to allow for the contraction during closing. A seaming-allowance will be placed at the back of the quarter. For buttoned boots two quarters should be used inside and outside, as shown in Fig. 134. This gives a better fit to the upper, and can be put to advantage in cutting up the leather. See chapter on Cutting-out.
Lining Patterns should be made with allowances for seams, stiffeners (where necessary, such as leather linings, non-stretching materials), and for mode of making, such as sewrounds, etc. Whole-cut linings should be cut with a spring in them, to prevent foul material when made. Shoe lining should not, for comfort, have a seam at the back.