The Story of the PLUMP Outsole

We believe in the power of collaboration, and the story of the PLUMP is just that! We started a journey 2 months ago, with the intention of helping footwear design become more open source and more collaborative. As we progressed through this journey we didn't know how these collaborations would come to life, in particular how we could link the community to brands through #lacelesschallenge.


1 month ago we asked you what sole you wanted to design on. We looked through the Vibram catalogues and selected two that we felt you would love... and you did - MANEGO and PLUMP created huge discussion and debate and the vote was tight! In the end the PLUMP was chosen and we proceeded with the design phase. A week went by and we could see already the love the sole was getting with a single post of the sole collecting over 21000 impressions. We then we got a message from one of designers from the community, aka Defne Yalkut. She recognised the sole unit; recognised it and knew every detail of it because she designed it when she was working at Vibram! Defne was so passionate about the #lacelesschallenge, and all your designs, we decided to link back up with Vibram to give you a deeper dive into the sole unit. So here it is - from the community to the brand and back again.

Defne made her way into the industry after completing a Masters in Fashion Design and Marketing in the home of Italian design, the Domus Academy. After several years designing apparel and bags she began working for Vibram. This is where the PLUMP was born!


The sole was to be Vibram's solution to something that gave you the feeling of walking on pockets of air, whilst bringing something that visually progressed the industry; a sole that was versatile, lightweight and extremely comfortable. Large rounded volumes create depth and cushioning where you need it giving the sole an extremely comfortable step in feel. A new material called Moreflex allowed the team to remove heavy rubber from the sole and create a single material unit that is durable and feels incredibly lightweight. Understanding that comfort relies not only on geometry and material, Defne and the team looked into the biomechanics of your gait to design in cuts and grooves on the bottom that wrap up to the profile following the Biomechanical "S" of walking. With the sole unit on hand, we can testify the design of Plump gives you a new experience of comfort; almost, dare i say, giving you a feeling of floating.


Defne, went straight to paper to make her ideas visual. Sketching out a bunch of concepts before eventually, with the team, narrowing down to one she felt matched the emotions she wanted to evoke with the design. Going a step further she rendered up the design including colour, shading and grooves so the team could imagine the the final product.

Then after a Vibram sign off, she created 2D technical drawing with the team, capturing every detail of the cross sections. This was then translated into 3D. A CNC milling machine can read this file and will cut away at a wooden model until it matches the 3D file. Then this can be used to initiate the casting process for metal mold making and we are almost there!

With the plump, Vibram used a compression molding process because this gives the best accuracy of fine details that make the PLUMP as beautiful as it is. So they cut EVA into a rough shape, insert it into the mold, heat it up and press. After a very quick cooling process to ensure all those fine details are stuck in place, the mold is opened and the PLUMP begins its beautiful life awaiting to be a part of your concept.

We thank Defne and the whole Vibram team for their hard work on this. I am sure you agree that the result is amazing, and we believe this is only the beginning for this sole unit. We are looking forward to more designers and brands to pick it up. As for Defne, she teaches in “Istituto Europeo del Design" in Milan and works as an Innovation Design Consultant with Vibram and across the outdoor sector. She is a designer that is definitely worth keeping an eye on in the future and she can't wait to see the winner of the #lacelesschallenge!