SUCCESS! First post here but I wanted to share my latest CNC machine adventure. My previous experience is a Shapeoko 3 where I learned a LOT about CNC, CAM and general G-coding. I have on the way a 6040 but I also picked up a 3020 to do some tests on and to learn, its a limited machine but that limitations allows for less expensive screw ups.
Just for any one else looking to get a 3020, mine came with 1404 lead screws and NEMA 23 motors (1.8 deg, 200 Step), which gave me the following settings:
Full step : 50 steps per mm
1/2 step: 100 steps per mm
1/4 step: 200 steps per mm
1/8 step: 400 steps per mm
1/16 step: 800 steps per mm
1/32 step: 1600 steps per mm (my A4988 drivers don't support this but it's theoretically possible with another driver chip)
Other issues are the Z-axis binding a bit if you go too quickly, but honestly you don't want to go the speeds it binds at (around 400mm/min). I have it limited to 300mm/min to solve this.
Anyways, here's the video of all the info:
https://youtu.be/7-YQ8cqFXP0
Hope to hang around more and learn!