Solidtec meets KnapsackInnovatively made bag

What always fascinates us about our work? Getting to know the exciting and creative projects and products to which we can contribute with our high-quality injection molded parts.

This was also the case when we met designer Christoph Ulrich Seyferth and his "Knapsack". This innovatively manufactured bag not only convinces with high-quality materials and a cool look and feel. Before it was ready to go, we advised Christoph Ulrich Seyferth on the design in terms of function and feel as well as on product design, material selection and manufacturing.



What is Knapsack?

The special feature of the "Knapsack" is in the detail. The steel band processed in the edge of the bag hugs the body, so that the bag closes even without a zipper. This bag edge can also be folded over. This not only makes the bag more theft-proof, it can also be made smaller by folding the edge back several times.

Christoph Ulrich Seyferth developed a smooth-running ball bearing consisting of a metal hook and a holder made of POM plastic so that the folding of the bag's edge literally works in the blink of an eye. Solidtec injection molded the parts for this bracket within a few days. The advantage of rapid tooling over 3D printing is literally obvious here and in the durable handling, because: The holder pieces must be UV-resistant, robust, stable, color-fast and as smooth as possible so that the bag serves its purpose for many years.

Special attention was paid to the interaction of the components to guarantee that the edge of the bag can really be folded down smoothly. It was important that the metal hook could slide when the bag was closed. The interaction of the hook with the holder we made makes this possible in the smallest of spaces - the special and casual handling of the Knapsack will work perfectly for years.



Rapid tooling for very short runs

The bag itself is only produced in small quantities by Christoph Ulrich Seyferth and requires different colored plastic parts depending on the fabric and design. With Rapid Tooling we produce these in small quantities and highest quality.

You see: Even for "unusual" projects, we close the niche between 3D printing and large-scale production with Rapid Tooling and fulfill the wishes and expectations of our customers with pinpoint accuracy.


If you would like to know whether injection molding is also suitable for your project, please contact us!

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