So after some days of more or less good performance, i have the main suspect, one motor really seems to stuck and stutter and delay all the rest, here is a better video of how it looks cleaned boards with air pressure, didn’t help, any ideas?
Take the belt off and see if it still does that. It could still be a bad connection, too tight of a belt, crud in the belt, or bad stepper.
Thanks Ryan alredy for all your good answers, will test all that soon, im gonna post very soon a super exciting project done with the mpcnc! (gonna be part of a fashion show!)
What!!! Can’t wait.
I fought something similar. I was using cat6 and found there was a broken wire inside the cladding.
Hey Josh! thanks for your reply, do you mind elaborating on that ? maybe with images of the parts you refer to ?
I have a feeling something is broken somewhere and it drives me nuts 
did google images on what you said and guess I understand what parts I need to look at but just to be sure
The copper wire was broken inside of the sheath so you couldnt actually see the broken wire. I removed the connections and soldered new wire back to the board.