End Mill 19.7-Mil Diameter, Square Profile 5-Pack bit and they are carbide tools

and they are carbide tools made in the US

Apply a "puddle" of mineral oil over the surface of the board before cutting so that the copper and fiberglass chips/dust stay suspended in the oil and out of the air

Prometheus is the tool for that

Anti-backlash lead nuts on X and Y

or for your business

End Mill 19.7-Mil Diameter, Square Profile 5-Pack bit and they are carbide toolsA premium PCB end mill capable of 20 mil isolation. The square profile means you'll cut very precise (repeatable) gaps across the surface of the board. At 20 mils in diameter, it is more robust than the smallest end mills we carry. Made from submicrograin carbide. Pack of 5