Having produced the design on the last, the masking tape is removed to produce the inside & outside formes, a flat representation of the 3D design. From these, the mean forme is produced which is simply a combination of the inside & outside formes.
After cutting down the centre lines, the tape can simply be peeled off
It’s important to keep the curvature of the rear when flattening the tape. A slit was made approx 10-15mm from the heel line to absorb any excess tape to avoid any distortion.
It’s also important to avoid too much distortion around the front centre line around the Vamp Point (VP2) at the expense of distortion around the front feather edge. Slits are made perpendicular to the feather edge around the toe point to aid flattening.
The inner & outer formes can then be cut out. Slashes are cut out periodically alone the various curves so they can be replicated when producing the mean forme. A notch is made to indicate the side of the slashes not to be used when tracing out later. It’s standard practise to also make a notch in the feather edge of the insole forme to avoid any confusion later on.
The first step in making the mean forme is to draw a horizontal line on the paper and mark the Vamp Point. Place the outsole forme VP where marked and pivot the forme so that the toe point is also on the line.
The outline of the outsole and design curve are then traced out. The notches making it clear to trace the opposite edge for the curves.
To finish transferring of the outsole design to the mean forme; i) reapplying the missing sections of the curves, ii) use dividers to mark out a 25mm lasting allowance along the feather edge and iii) extend the back line by 2mm at the topline, 4mm halfway to the heal point and 6mm at the heal point. The easiest way to maintain the rear curvature is to place the outsole forme’s back line along these points and re-trace. The curvature is then just extended for the lasting allowance. Note: it’s necessary to extend the heal line to provide room for a heal stiffener during the lasting process
The process is repeated to add the insole design to the mean forme. However there are a couple of variations. Initially, once the Vamp Point (VP2) and toe point have been positioned correctly, just trace out the feather edge from the toe point to the vamp curve and the wingtip/toe-cap & vamp curves.
Next pivot the insole forme at the Vamp Point until its Back Point (BP) is inline with the same point on the traced out outsole. The back line can then be traced. Note: in this case both back lines were within 1-2mm of each other so an average is used. If it is more than that, then the mean forme needs to be drawn with the two distinct back lines
The insole design traced onto the mean forme. The wingtip and vamp curves both converge with the outsole curves towards the feather edge so these will be merged apart from the centre sections. The two other areas of difference are the tongue/topline area and the curve for the heal counter, which is quite different between the insole and outsole.
Placing the two heal points together its quite clear that the insole’s counter curve is 6mm further along the feather edge (pointed to by pencil). Therefore I’m going to pull this back on the mean forme drawing but not still keep them as two distinct curves.
The remaining issues are the differences in the tongue area and also the topline. An average line will be taken for the tongue area. Due to the anatomy of the foot, the inner ankle is higher than the outer ankle. This means, at the point just below the ankle, the outsole top line should be between 51-57mm above the feather line and 57-64mm for the insole. My insole topline drawn on the last is actually lower than the outsole topline, so I’m going to raise it to be 5mm above the outsole topline.
With the rework to the tongue area and toplines. However the introductiuon of two distinct toplines means the design will also need two lower collar lines.
The collar needs to be sufficiently wide enough to have room for two stitch lines either side of a line of brogue holes. A generous width of 12mm was chosen based on hand stitching and my Wuta brogue punches (with the option of grimped edge).
Finally lining curves were added. The toe-cap lining starting 12mm forward of the Vamp Point and then curving down between the wingtip and vamp curves. The aim is to avoid each of these lines overlapping, as these are the areas where leather pieces will be joining and therefore added thickness.
Completed mean forme with tracing slashes cut ready to transfer to make the pattern pieces. A row of ’Swan Neck’ eyelets were also added which mirror the curvature of the collar