The insoles are J&Fj Baker Oak Bark Cut Insoles. Rough cut insoles are cut to the last bottom pattern plus a 6mm margin. With hindsight I should have mae that 8mm or even 10mm. The final trimming would be done once moulded on the lasts.Typically the insole is between 6-6.5mm thick and made of very tough leather – not the easiest to cut!This first task is to mould the insoles to the bottom of the lasts. As insole leather is quite rigid, they need soaking in warm water for around 15 minutes, which makes them flexible enough to be moulded to the curves of the lasts.The insoles need to be held firmly against the lasts until they have dried, when their original rigid property returns. A good way to do this is to wrap a bike inner tude around them while they dry. So two inner tubes were sacrificed – they were also cut lengthwise to make two strips per inner tube.The inner soles were secured to the lasts by hammering in three lasting nails and then tightly bound with the inner tube strips.The inner tubes were bonds quite tightly so I was concerned there was nowhere for the added moisture to escape and they might go mouldy. So after 48 hours, once the insoles had had a chance to ‘set’, I rebound each last with a single strip of inner tube which exposed sufficient leather to guarantee they would dry out on a sunny window sill.The insoles were roughly cut back to the feather edge of the lasts using a shoemakers knife. The knife needs continual stropping to keep it’s edge sharp.The final shaping was achieved with a shoemakers rasp and file. I wanted to continue the curvature of the lasts in the insoles tokeep a tight waist to the finished shoe … I hope that turns out to be a good idea!! I was surprised in the change in colour between the bound and unbound areas when the insoles were drying.The heal line was marked – in this case 70mm from the back of the heal. I had read somewhere that a good guide is the width of thewidest part of the heal plus 5mm. The outer holdfast line is typically about 7mm from the last’s feather edge. However, as I’d angled the edges of the insole this made this task much more difficult. As I had a card template of the last bottom I was able to make a copy and reuce this by 7mm and then trace around it to give the holdfast line.The cut around the holdfast line nedds to be no more than 3mm, which just happens to be the same blade depth of my woodworking marker. So this was used to cut into the insoles to a depth of 3mm.The 3mm deep cut was moistened before a channel opener tool run around the cut line, which helps when reducing the depth of the outer edge of the insole. A feathering knive is a very handy tool, designed for making the holdfast. It has a 90 degree angled fence, or guide. The vertical section runs along the edge of the opened channel while the horizontal section of the fence runs across the top surface of the insole. The knife’s cuttung edge is set 3mm lower than the horizontal fence. This enables the outer edge of the insole to be cut away to the 3mm depth required.The completed outer edge of the holdfast with a 3mm step. The inner edge of the holdfast is marked 6mm in from the outer edge.The same approach is used for the inner edge – cut to 3mm, moisten and open up the channel.Cutting down the inside edge is tricker as the cut has to be made at a slight angle, which doesn’t suit the feathering knife as much. i used a combination of the feathering knife, held at an angle and a normal skiving knife to complete the innder edge. The leather cut away was retained as it can be glued back in place once the shoe upper has been stitched. The cut away areas were moistened and then burnished with a bone folder to improve the definition of the holdfast edges and strengthen the area by compressing the leather.Lines were then drawb across the holdfast at 6mm intervals, to mark where the stitching holes will be made. The spacing at the roe was dropped to 5mm and the lines fanning out from a central point.An insole awl has a curved tip for making the stitching holes in the holdfast. The area is moisened beforehand and it makes it noticeably easier if the awl is stabbed into a block of beeswax between each hole. The awl ispushed through at the very base of the inside of the holdfast, pointing it slightly downwards to maximise the depth (and therefore strength) of the stitch. The drawn lines towards the inside of the insole will be used as guide once the uppers are lasted.Completed insole ready for lasting the uppers.
