I Filed Backwards 2500 Times, And This Happened

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I put files to the test to see if back-dragging dulls a file like many claim. I test coarse, medium, and fine files after I built a large testing rig to stroke tens of thousands of times. I also test if back-dragging unclogs files. I use the slow-motion camera to analyze the results and use a microscope to observe all the files!
Get the Pferd Files Here!
fireballtool.c...
Our New Hardtail Vise
fireballtool.c...
The Gloves I Wore
fireballtool.c...
How did I build this Machine?
• The internet says I fi...
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