Fusion 360 Oval Sinker Model

I need a native Fusion 360 (Personal licence) file for a classic oval egg-style fishing sinker made of lead, sized in inches and weighed in ounces. The piece must carry a continuous helical groove that bores all the way to the core, with each end of the cut blending smoothly back into the surface rather than stopping abruptly. I will specify the exact coil count once we start, so please keep the model fully parametric—changing the turn number, pitch, or overall weight should update the geometry without breaking features.

Key points you must hit: the body is strictly oval, the groove depth reaches the centre, and both groove ends curve elegantly into the lead surface. Please stay inside the feature set available in the free Personal edition of Fusion 360; no add-ins or paid work-arounds.

Deliverables
• Fusion 360 (.f3d) file, editable and parametric
• Optional STEP or STL export once the .f3d is approved

I will run a quick print and weight check; if the model balances and the groove flows cleanly to the core, the job is done.