first off I am new to cnc machining. I am like a monkey with a football, I have no idea what im doing. But I am a fairly quick learning monkey so....
I started out using scrap wood to test on which was a good idea cause I had no idea how important all those little numbers all over the place were. I have moved to a point where I can generate the cad, align it to the table, align the cutters (zero it all out on the machine), load gcode and hit the go button. Results of course at this point vary.
I have a taig table top mill, generating cad on solidworks, using sheetcam for the cam/g code generation and mach3 to drive the machine.
For the part I am essentially learning on, I am using a 1/8 diameter 4 flute carbide endmill and I am cutting into 1018 mild steel. I do not have a coolant setup or an air blower yet (or for that matter a containment cabinet yet).
The settings I am using are .042 inch depth per pass, feed rate of 3 inch per minute, plunge rate of .5 inch per minute, spindle speed 2800 rpm.
So far, the chips are all tiny and fairly consistent. The mill doesnt seem to make any harsh screeching or other noises I would interpret as 'overdriving something'. I have a lot of manual mill experience but also all self taught. When it is cutting it sounds ok but I am still learning what ok is on a cnc machine.
The parts I have been getting off the machine are ok but I am still in a learning mode for sure. They are pretty hot when I pull them out of the machine. Do those feed rates I am using look ok or am I under driving it causing excess friction (or pushing something a bit hard)?
Any advice or opinion would be appreciated.
3IPM at 2600 sounds about right may be a tad slow for a 4 flute.
You could also try 6IPM at 4200 or 10IPM at 6700 and see how that goes. You may be able to speed it up with those settings and not have any issues.