Among the variety of minimal running sandals based on traditional huaraches of the Rarámuri/Tarahumara people, I failed to find any existing designs which satisfied me, so I developed my own to solve the following problems:
The lace is versatile paracord. It can simply be crossed at the ankle attachments, but I made copper retainers which serve similar function (elevation and movement) without as much wear on the lacing. Similarly, the lacing can simply be threaded through the sole, but I made attachment loops of durable rubberised fabric to avoid exposing the lacing to the ground. The sliding fisherman’s knot provides quick/easy tension adjustment. The ends are whipped for grip (tension adjustment) and easier threading.
Support for the Achilles tendon was my primary motivation because simply lacing over the tendon (as most designs do) left a persistent dent in my flesh. I also wanted to avoid using webbing lacing for various reasons. The lace will quickly wear through the webbing eyes if they are not given some protection, so I applied polyurethane (shoe repair goo) which has worked very well.
The toe attachment is made of four strands of paracord which stiffens over time and has worked very well. The ends can be sewn/whipped and melted/flared, but in this case I made a mould for a polyurethane terminal similar to those found on commercial thongs.
The extra holes at the forefoot remain ready to accept additional lacing for situations which require greater stability.
The sole is microcellular foam rubber (made for custom footwear/orthotics) which is durable and floats. A non-slip foot bed is essential, especially with only three attachment points. Soling material generally has a wire-brushed surface treatment (in preparation for gluing) which provides just enough friction (at least until it becomes too polished from use, but then it can simply be brushed again).
Simple construction technique applied to high-performance materials yields a product which is more useful/versatile, in contrast to the specialised/monolithic/disposable production of modern industry.