Hi everyone,

I'm currently building a CNC router of 1.8x1.2 meter to cut wood (and probably test aluminium).
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I use aluminium profile 8 series and 20mm aluminium plate. 4X NEMA 23 with a 48V PSU and a gecko G540. Here is the specs of the motor: (381 oz In. Holding Torque, 2.55V Rated voltage, 3.5 Amps Current Per Phase, 0.73 ohms Resistance, Inductance 2.8 mH).

I had a proposition to use for the X and Y, 20mm lead, with a max speed of 500 IPM at an acceleration of 0.15G. For the Z, 10mm lead, with a max speed of 300 IPM at the same acceleration. My goal is to have a resolution of 0.01, an accuracy of a least 0.1mm.

I have several questions:
  1. Is this general design seems to be ok?
  2. Are my max speed and acceleration calculated correctly? Or should I take 20 or 10mm lead?
  3. Is it a correct speed / acceleration for the size?
  4. Do I need to have a ballscrew preload torque?
  5. Is the position of the linear bearing/ballscrew good?
  6. Which space should I have between linear block?


Thanks for your help.