One of the essentials to creating comfortable, and visually appealing footwear is often overlooked and underappreciated. Lasts, the foot form used shape the shoe, is perhaps one of the most challenging aspects of shoemaking, and is responsible for many elements that could easily render a shoe a complete failure. The mission of any great shoe is to make you forget that you are wearing anything at all. This starts with the last.
Last selection and last making requires a deep knowledge set and is more of an artform than anything else. There is often a misconception that 3D scanning a foot will solve the challenge of fit, the truth is that building a shoe off of a model of a foot will result in something that looks ugly and fits poorly. This is because lasts shapes the foot into the desired application. Thus, the first step is to understand what you are trying to achieve. For our example, we will focus on what makes a great performance shoe, but the same principles and ideas can be applied to all categories of footwear. The only difference is in how you tune the last for desired results.
The following are the five major components that one must consider when selecting or designing a last. For the sake of this article we have simplified these concepts as best as we could, but the truth is, last selection is highly complex and we could probably write a whole book on the topic.
The first place to start is to look at the metatarsal profile, the point from the big toe knuckle to little toe knuckle. Good performance lasts often have an offset. This is a better representation of the foot’s natural shape and accentuates the focus on the big toe and the ‘ball of the foot’ , which allows for the wear to receive great feedback and make dynamic movements. An offset also provides the ability to create a snug fit without pinching or constricting the ball.
The 50-50 metatarsal profile, which is basically straight across, makes the pattern making process much simpler and easier to commercialize. This is because the medial and lateral side can pretty much be represented by the same pattern or tooling. As a result, lower end shoes typically utilize such lasts but results in poorer performance and often leads to crimp zones on the foot.
The heel is a famous place for blisters in poorly designed shoes. The key to avoiding slippage, (the leading cause for blisters) is to keep the heel shape narrow in the upper and mid sections, while capturing the fatty base of the heel on the lower section. An additional factor is the rear rake, the ‘S’ profile of the back of the heel. Making a curve too deep can dig into the achilles attachment causing pinching and pain, while too little allows the heel to slide up and down thus causing blisters.
For athletic shoes it is essential to have a smaller cone profile. This increase the vamp length, allowing for the laces to be carried all the way up to the ankle, creating a snug and precise fit.
Conversely, lifestyle and dress shoes have a long skinny cone which opens up the ankle area. This is mainly for styling purposes as it creates the need for only a few eyelets and a small vamp. As a result this creates a shoe that emulates a particular style but lacks any performance features.
4. Ball Girth
In this section we look at different ways that volume can be distributed in a last. Ball girth refers to the parallel cross section of the widest points of the forefoot. The profile of this section can either by more symmetrical (consistent) or asymmetrical. Lasts that are asymmetrical usually result in a better fit but are more challenging to design and build. While easier to build, symmetrical lasts result in extra space in the shoe. This typically leads to a shoe that will have more wrinkling and a more sloppy fit.
A performance last tends to have a ridge line that follow the big toe or first metatarsal and you will find there will be very little volume in the little toe area. This will result in a roomy but snug fit and less wrinkling in the vamp or toe area.
Many components of a last can be modified to create certain styling demands. The last can dictate how the fabric lays on the shoe and where the stitching lines are placed. Some designs require a tall sidewall to create a certain look as shown below. Curved lasts with pointed toes can also be added, which is more typical in women’s dress shoes.
Fit is more important than ever. With more consumers buying online, brands run the risk of reduced margins due to returns of poor fitting product. It is critical for a brand to have a consistent fit throughout it’s line as it provides customers with predictability. Things like the stretch characteristics and thickness of material can drastically alter fit and must be carefully considered to obtain this consistency.
With lasts influencing comfort, fit, and styling, brands must have a clear grasp of the key characteristics that they want to represent when engineering or selecting their last. In many ways a brand’s DNA is represented in the last that they use. For many of the most iconic shoes, the profile and shape that the last created was more significant than the logo, design, materials or colors that were used. Without a doubt lasts are fundamental to creating great footwear, yet is seemingly overlooked in this industry. Last making a black art of shorts as there are scarce resources available for people to learn this magic. We hope that this helps touch on the high level concepts, and would love to know what you think.
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