Mesh rebuild freecad knob

The request

Attached is an STL of a knob exported from a CAD application: a round body with a chamfered top edge and a hexagonal socket in the underside. Rebuild it as a parametric part named exactly `knob`, standing where the mesh stands (Z up, same origin, base on the same plane), with controls `diameter` (±10 mm around the mesh) and `height` (±5 mm), and a hex socket that fits a 8 mm key. Keep the mesh imported in the part while you work. Measure the mesh first.

What the AI judge checks

• The overall form matches the reference: the same kind of object, the same silhouette from the matching angle
• Proportions match: the relative sizes of the major dimensions agree with the reference within what the eye can judge
• Every major feature visible in the reference (holes, slots, bosses, tabs, lips) is present in the result
• Those features sit where the reference has them
• Nothing is present that the reference does not show — no decorative or unexplained geometry
• The top edge is chamfered, not sharp
• A hexagonal socket is visible in the bottom view

Measured checks

• one sub-part named knob (gate)
• volume within 3 % of the mesh (gate)
• bounding box within 0.5 mm of the mesh (gate)
• symmetric difference under the measured floor
• the socket clears a 8 mm key across the flats
• the socket is hexagonal, not round
• the socket is 6 mm deep
• the imported knob is still declared as an import
• asked the oracle at most once