Axle Preparation Study – Nail File Plus Sanding

To remove burrs and crimp marks, this axle was dressed with a "La Cross Sapphire Nail File," a nail file incorporating aluminum oxide particles as abrasives.  Under the microscope, the nail file itself looks like this:

After applying the nail file, the axle looked like this:

After using the nail file, wet sanding at grits of 400, P600, P800, 1000, 1500, and 2000 was applied.  (No 320 grit step this time.)  After each grade of sanding, a cotton cloth was used to clean the slurry from the axle.  The following are images after each sanding step.
400 grit

P600 grit

P800 grit

1000 grit

1500 grit

2000 grit