I saw this model of 3D-printable Velcro and wanted to experiment a little with it:
Printable Velcro von MM Printing | Kostenloses STL-Modell herunterladen | Printables.com

Others have already proven that the technique works in general. But what if we could tune it a bit? For example, by changing the shape and size of the pins to increase the holding strength. Maybe there is a particular configuration that results in the strongest possible connection.

What about a challenge?

Who wants to participate in a 3D-printed Velcro testing challenge? Everyone must use the same base size: 2 cm × 10 cm. Everything else is up to you: the number of pins, spacing, height, shape, material, print settings, etc.

Just design it, print it, and test how much weight it can hold. Of course, you’ll need two matching pieces.

The parametric STL can be found and downloaded for free here:
Gerridaj - G-Code Generator for Additive Manufacturing

and here:

https://www.gerridaj.com/community?workflow=43