Whether you call them flip flops, plakkies or thongs, these shoes are a summer staple across the world. Recently, the market for flip flops has become somewhat more interesting, with a small number of companies leveraging 3D printing and mass customization concepts to produce customer-tailored footwear. One of these companies, Retraction Footwear, comes from Australia, where flip flops are a footwear essential.
Retraction Footwear was founded in 2018 by Australian engineer Brett Casson, who has spent the past two years developing a customizable 3D printed flip flop. There were a few factors that inspired Casson from the beginning: for one, he saw 3D printing as an opportunity to keep production local within Australia. Second, it meant he had the opportunity to create customizable products for customers. And third, 3D printing enables the shoes to be made with minimal material waste. Earlier this year, Retraction Footwear finally launched its 3D printed footwear product. Even more recently, I had the opportunity to try out a pair of the custom 3D printed sandals. Read on for my personal review.
Step 1: The order
Before revealing my thoughts on the physical product, I want to take you all through the ordering process for the custom flip flops. With most tailor-made shoe products that utilize 3D printing, one of two routes is taken: using 3D scanning or a similar biometric technology to capture the foot’s measurements or simply measuring the foot the old fashioned way—with a ruler. Retraction Footwear has opted for the latter, which does make the ordering process pretty simple from the user perspective.
In terms of the sizing, customers can input three measurements: length of foot, width of foot and arch height. The last two options are still fairly standardized, with a choice between narrow, normal and wide, and flat, regular and high, respectively. In any case, a detailed sizing guide does make it easy to find which category you fall into, though I recommend having a ruler handy just to be sure. To determine the cushioning level of the sandal, clients also have to input their weight category.
With the sizing selected, you then choose your flip flop color combination, including sole color, foot bed color and strap color. Presently, the color options are fairly limited, but the ability to combine various colors is fun. The color options, as of writing, are black, white, green and red. As you can see, I’ve opted for a versatile black and white color scheme. From the customer side, that’s pretty much it! You then place your order and wait for the delivery.
Step 2: The production
Though I wasn’t able to see the production of my flip flops first hand, I was provided with an in depth description of the process and an exclusive video clip of my shoes being made. I’ll walk you through it. Once an order has been placed with Retraction Footwear, the customer’s options are processed and prepared for printing. From there, the 3D printer gets to work, depositing layers of a flexible filament onto the print bed, building up the shoe from the sole, to the inner cushioned lattice, to the footbed. Finally, the strap component is 3D printed separately.
The printing process itself is carried out using heavily modified Creality machines with 400 x 400 mm print beds (which can accommodate large shoe sizes). Casson tells us that the printers have been converted to direct drive with high-end extruders and hot ends, which improve the overall quality of the print. For material, Retraction Footwear uses Ninjatek’s NinjaFlex TPU filament, which offers a high degree of flexibility while still remaining strong and durable.
Once the printing is done, minimal post processing is needed: a Retraction Footwear employee simply sands down the bottom of the sole, and carefully inserts the strap and secures it with glue and a reinforcing bit. The finished product is then quality checked, packaged and shipped.
Step 3: The first try
After a few weeks traveling across the globe, my Retraction flip flops arrived at my home in Montreal. Even the packaging is worth mentioning. Retraction Footwear hasn’t settled to ship its product in a classic shoe box. No, instead it packages its shoes in a cardboard tube fitted with 3D printed end pieces—which made the unboxing all the more exciting.
My first impression was largely positive: the shoes looked just like I was expecting and the fit was great. The movement and toolpath of the 3D printer can still be seen on the surface of the flip flop. This texture (which to some might seem unfinished) is a footprint of the technological process that made it—a feature which I really like. The texture is also gradient, which lends a certain aesthetic appeal when viewed from close up.
As I ordered my soles in white, I was unsurprised to find that the shoes did not keep their pristine color for very long. But, thanks to the plastic nature of the shoe, they are easy to wipe down and clean, especially compared to more traditional foam flip flops.
In terms of comfort, the 3D printed flip flops are pretty impressive. As someone who spent many (many) years exclusively wearing Old Navy flip flops in the summer, it has been somewhat of a relief to not suffer from blisters within the first hours of wearing these custom ones. The lattice cushioning is distinctive compared to foam, and I don’t anticipate they will wear down as quickly.
I should also mention that the Retraction shoes are designed to have a thicker heel, which I think makes a positive difference for comfort. This is also supported (literally) by the customizable arch height, which hugs the bottom of the foot and offers more cushioning. The one thing I cannot speak to yet, but I will consider updating my review in future, is durability. So far, it seems like the cushioned lattice is pretty resilient (they are quite bouncy even), but I will see how they do after some more wear.
Conclusion: Not a flop
At a basic level, the flip flop’s simplicity makes it well suited for 3D printing. While most shoes require some sort of upper, flip flops are all sole (and a little bit of strap, of course). This not only makes them relatively straightforward to produce using 3D printing, but also helps customers to visualize exactly how the technology has been applied. That is, there is no hidden midsole: you can see on the surface how 3D printing has been used.
I’ve now been wearing my custom 3D printed flip flops, courtesy of Retraction Footwear, for about a week and I honestly can’t find much to complain about. They’re comfy, haven’t hurt my feet, have good arch support and have good grip. The sandals, which retail for $86 are available to order and can be shipped worldwide. Until August 31, 2020, the company is offering free international shipping.