Here is a very simple but highly useful accessory I made from a 13x13x40 mm block and a broken end mill. And here's a 76x140mm flated surface. There was some vibration due to the unbalanced rotating mass, something that I fix later adding a simple counterweight. And of course I took advantage of a not-perfectly…
Assorts Large head size 4 Inch/ 100 mm diameter Fly cutter with
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Assorts Large Head Size 4 inch/ 100 mm Diameter Fly Cutter with Carbide Indexable Tip Facing Tool (R8 Shank (7/16 UNF Drawbar))
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Large head size 4 Inch/ 100 mm diameter Fly cutter with Carbide
Assorts Large Head Size 4 inch/ 100 mm Diameter Fly Cutter with Carbide Indexable Tip Facing Tool (R8 Shank (7/16 UNF Drawbar))
Homemade DIY Fly Cutter, Double Edged, for Milling Machine. : 6