As a shoemaker I am always looking for new fabrication techniques- there are hundreds of separate steps to make a shoe and many ways of doing each one. I have always wondered how else a sole might be attached to a shoe 'upper.'
Traditional forms of attaching shoe soles to material uppers have included glueing or stitching (sometimes both) of the upper material to the sole.
The glueing process is toxic and messy. The stitching process is heavyweight and very time consuming.
I really dislike using adhesives- neoprene is a common one for footwear. It contains some horrible stuff that can do some serious damage to people and wildlife. I have attached an outtake of a safety data sheet from one of the leading brands of shoemaking glue. Pretty depressing reading. During the process of attaching a pari of soles, you will inevitably come in to contact with it in some way, even with PPE. Add to this the fact that to make the glue adhere correctly, you need to abrade the leather of the shoe, thus causing particulate of leather to become ariborne and possibly inhaled. Having spent years working with the sticky stuff, I have begun exploring ideas about new ways to attach the sole to the upper without using adhesives.
The other benefit with having a modular shoe means that items can be interchanged, thus increasing longevity and allowing for easy customisation.
The design that I am outlining in this project is still in progress as I publish this Instructable. This is my method for creating a shoe without using glue, I encourage the reader to try and find their own ways also!
For this experiment, whilst avoiding glue I will also try to use the fewest possible number of specific shoemaking tools or machines.
A basic list of things you will need:
Some material for the upper (leather/fabric/PU leather- the choice is yours)
A sewing machine
A 3D print printer (this assumes you have access to a computer and some software such as Fusion 360- free of charge to use if you use it for an enterprise earning less than 100k / year)
Some flexible filament - TPU
Cord or elastic