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.
It is difficult to give any single rule of proportion fixing the height of a vamp, owing to the differences that have to be made between boots and shoes, high and low heeled work, and for accommodating the various sorts of toe-caps. It is usual to make vamps for shoes lower than would be the case for boots, and high-heeled work requires shorter vamps than those used for low heels. A low vamp for low heels would be exceedingly uncomfortable. If vamps are made too low they give the appearance of wide joints, and cause more waste in cutting. If the vamp is to be capped it should be made higher than it would be without caps, the kind of cap - whether straight (Fig, 126), pointed (Fig. 122A), or peaked (Fig. 126, B) - deciding the difference. It is recommended that as far as possible the heights of vamps be reduced to a proportion of the forme or last-length, or in relation to the position of the joint of the foot. Reducing it to a ratio of the last-length has advantages over the forme-length; the former being preferable, because the forme will vary in length with the fitting of the last, whereas the length of last will be the same in the various fittings of the same size. As an instance, one-fourth for low and one-third for high vamps, for women's and children's work, and one-third for low and two-fifths for high, in men's and boy's work, would give a basis for regulating vamp-heights.*
The length of wing admits of more definite treatment by rule than vamp-heights, and should be decided upon by approximation to the instep-line of the pattern. A long-winged vamp is expensive to cut, and in the made-up goods prevents the easy entrance of the foot, besides causing much difficulty in paste-fitting and stitching. Vamps with short wings are cheaper to cut, especially if the material to be cut requires a system, as Fig. 122A.
The curve, throat, or cue of the vamp should be designed in harmony with the style of toe of the last; a narrow toe looking better with a smart, and a square toe with a squarer cut curve. The curve for a button-boot vamp should be designed easy, giving a little extra freedom to counteract the tension caused by the fastening of the button-piece. Lower vamps are used also for this reason, upon button or other work causing a tying tendency, to prevent abrasion on the foot. High vamps should not be used for lasts that fall away suddenly below the instep, but, if they are required, a "fitting" or "shover" should be used in making, and care taken not to spring the toe of the upper. Vamps for derbies and similar designs should not be high, unless proper provision is made in the last to prevent any cutting tendency of the edge upon the foot, and in the pattern to balance the effect of the curve on the standard below that of the crease-line of the vamp (compare E and K, Fig. 121). The vamp cut from a standard, as shown in Fig. 121, would be pulled in lasting from E to K, and the tension that would fall at V would cause that edge to bind when on the foot. It may be often remedied by "deadening" the toe when the shape of the toe of the forme is as shown in Fig. 120, where the dotted line VN shows the crease-line. Care must, however, be taken not to put the crease-line below the end of the toe, or the upper will be too tight round the edge of the last and difficult to "last in" at the waist. Vamps may be cut to interlock, and in cutting small areas this is of great advantage. The extreme corner of the wing may be removed, but must not be overdone. Fig. 123 will illustrate this principle, and it is specially adaptable to vamps with long wings, only it often requires some sacrifice in the smartness of the shape to effect the full economy desired.
3 Children's work should not be cut, as a rule, with very low vamps.
Fix the height of vamp V and length of wing W (Fig. 120). Join this with a line, and find centre Y. The curve of the vamp may be made to pass above Y, at a distance of one, two, or three-ninths of an inch, according to the style required.
This is illustrated by Fig. 121, and is described on p. 143. It is adaptable to designing circular or square vamps that have to be locked, and fitted on the flat system. To attain the latter, draw the crease-line Ved (Fig. 121), and through H draw a line parallel to YD, and where this crosses the line that passes from R to W measure downwards the distance VH, and complete by sketching curve of vamp.
The Springing of Vamps is resorted to for several purposes. It is an old custom, owing its primary origin, no doubt, to the kind of pattern then in vogue, and used to give "draft," or set, to the vamp. It is used also for economical reasons, especially with patterns that are cut from lasts that have a small amount of spring, and are flat in the toe. In fabric-lined work, if the vamps are "sprung " it prevents the foulness of the lining when the boot is completed. Vamps that are cut from standards that are " dead," spread open, and are not so convenient to use in cutting leather to best advantage. Fig. 126 shows a vamp, Abc, cut as marked on the shoe-standard. The half DE shows the vamp with more spring, and it should be noted that the lasting edge is increased by twice the amount of EB at the toe. The dotted tracing shows the same vamp made more "dead," and in addition to the increase in the distance from the central line xy, before alluded to, the edge has decreased at the toe by the amount BH. By springing vamps greater economy is observed in cutting leather by interlocking, and the edge of the upper is increased in length of that over the standard, so that extra material has to be lasted in. On the other hand, the opposite is the case with vamps that are too "dead." The nature of the leather must be taken into account when springing vamps. It will be seen from what has been said respecting the lengthening of the bottom edge of the upper, that to spring vamps for materials that are stubborn to last would make it difficult and impossible for the boot to be lasted without wrinkles.
The amount of spring to be used over that of the standard * is as follows :Patent leathers .........none on any account.
Light wax calf, Russias, satins, and 1/8 in.
Firm kid-calf .........
Soft English and German (soft) kid, glace,and very supple wax calf... 3/16 in.
If the standard bears the relation to the forme as illustrated in Fig. 120, the above amounts should be modified.
If standards are drafted properly, the springing of vamps may be omitted with advantage in cheaper classes of work.