Still in work, I might change some things.
-20x20mm aluminum extrusion.
-CARRIAGE_OFFSET (from magnet center to back surface of the main carriage part) : 31.305 mm.
-Distance between magnets (center to center) : 45mm.
-Tension screw M3x60mm (or less).
-Wheel diameter 21.5mm.
-Wheel screw M5x50mm
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