Question About Roughing Pass

[jenordyke]

I am quite new to both CNC and Vcarve Pro. My first 3D project is the classic "waving flag." I am machining to a boundary vector, and the 'deepest' trough in the waves is about 3/8 inch. My roughing pass: 1/4 EM, a .1 depth of cut, 20% stepover, .03 machining tolerance. My expectation was that the roughing pass would clear (leaving at least .03) everything the bit could reach and Z would "flow" as necessary up and down. What I get is a few passes forming deepening 'shelves,' and there are many places within the machining region that the 1/4 EM could have cleared some material but doesn't touch, leaving too much material for my 1/8 BN to clean up in a single pass. I find that if I change depth of cut for the roughing bit from .1 to .05, the roughing passes form more (and shallower) shelves and leave less work for my finishing bit to handle. Is this more-or-less how it is supposed to work? If so, is there a good rule of thumb to guide me in setting up the roughing depth of cut to find a sweet spot between amount of material ultimately removed and machining time?

[adze_cnc]

There are two roughing strategies. You are using z-level. Use the other one.

[jenordyke]

Thank you, I've had such tunnel vision trying to learn a machine and software at same time I overlooked that.