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I am sure you already know this but if not the round knob facing you sticking out of the quil feed is for a controlled feed of the Z axis. This is necessary if you use a boreing bar and boreing head. A boreing bar will give you a hole that is precisely located and actually round. Because a drill bit uses multiple cutting lips (2) the hole produced is actually cam shaped. The job of a boreing bar is generally to clean up a drilled hole. The actual size of the hole is then determined with a reamer. A reamed hole is sufficient for general precision work. If a hole is just drilled and reamed, the reamer will follow the lobes of the hole produced by the drill.