Measuring the force between permanent magnets is a fundamental and well-established experiment in teaching electromagnetism, essential for students to empirically validate physical models. However, the implementation of this classic setup in large undergraduate courses is systematically hampered by the high cost, fragility, and rigidity of commercial equipment. This work presents the redesign, manufacture, and validation of a low-cost, open-source experimental device, developed primarily through 3D printing with diamagnetic materials. The main objective is to overcome the logistical shortcomings of the traditional setup by integrating a screw-type mechanism for distance adjustment, a standardized support for force sensors, and an alignment structure that supports repeatable coaxial alignment during measurement. This open-source design approach supports instructors in iterative improvement of lab activities and local adaptation of the apparatus. The validation results demonstrate that the device is a robust, economical, and flexible solution with adequate precision for undergraduate laboratory use. The creation of a replicable and low-cost tool facilitates the successful implementation of this established experiment in large-enrollment courses, promoting active, self-directed learning and contributing to the democratization of teaching tools in university physics.
http://orcid.org/https://0000-0001-8396-9711
Universidad Andres Bello, Santiago, Chile
[biography]
http://orcid.org/0000-0001-6066-355X
Universidad Andres Bello, Chile; Tecnologico de Monterrey, Mexico
[biography]
http://orcid.org/https://0000-0001-5880-1124
Tecnologico de Monterrey, Monterrey, Mexico; Universidad Andres Bello, Santiago, Chile
[biography]
The full paper will be available to logged in and registered conference attendees once the conference starts on June 21, 2026, and to all visitors after the conference ends on June 24, 2026