I'm trying to build a laser engraver/cnc router with Arduino Uno, CNC Shield v3, A4988 step motor drivers. I'm newbie about electronics and Arduino so sorry if I'm asking non-sense things.
I've installed GRBL 1.1 on Arduino Uno, connected A4988 drivers and two stepper motors (link to datasheet below). I used LM317 power supply for powering CNC shield. I haven't done any setting with A4988's trimpot.
When I try to send commands with Universal Gcode Sender, step motors turning well for single-axis movements. For example when I command to move it on X-axis, it seems it works well.
Here my questions are;
1- When one motor steps, the other motor also starts to work and vibrates without turning. Is this normal behaviour? Does CNC shield makes it "ready" as receives GRBL commands?
2- When I click on "return home" on GRBL controller software, step motor turns for several times and then stops and I guess skips (doesn't turn shaft) with a weird sound. What can be the reason for that? Does it means LM317 doesn't supply enough current? (I set it to 12V) Also A4988 doesn't heat at all, I suppose it should, can it be related?
3- Sometimes motor vibrates too much even for single-axis movement. Can it be also related to not enough current from power supply?
and also I'm thinking about connecting TTL/PWM laser diode with 12V/2.5A specifications, should I also consider this when calculating enough power supply? Or shouldn't I connect it to CNC shield, what is the best practice about this?
I'm thinking about buying 24V/5A power supply. For two step motors (0.4A * 2) and 2.5A laser I suppose I need 3.3A and as step motors are 12V and they will act better with higher voltage, I will buy 24V. Is this correct calculation or should I consider some other things?
- My stepper motors' specifications:
- A4988 step motor driver specifications:
- CNC Shield v3 technical data and instructions:
- The laser module I would like to connect: