I'm scribbling some designs for a Z axis conversion for my RF30m drill/mill.
I can estimate the force I need to apply to the cutter to force it to cut, OK. But, what kind of force can the cutter, e.g. end mill, produce in the down direction? (i.e. as it tries to screw itself into the work piece).
Can I rely on a spring (pulling the quill upwards) for backlash removal? (If I can, then I probably use the existing rack and pinion thus keeping manual use as an option)