USB connection unstable on 4.2.7 board

  • I have used my Ender 3 for 3 years with the original 1.1.3 mainboard, driving it by USB from a Raspberry Pi running Astroprint. It has always worked very reliably but with noisy stepper motors. I have just upgraded to the silent running 4.2.7 mainboard and now it loses its USB connection randomly after a few minutes. The printer just freezes the extruder and bed temperatures are maintained but my Astroprint screen says it has lost USB connection with the printer. I can manually reconnect using the Astroprint screen and regain manual control of the printer to raise the head and return it to home, but the print is lost. Has anyone else had this problem? I am trying to determine if it is a firmware problem or have I got a faulty board? The new board prints reliably and silently from an SD card.

  • @john3d Perhaps this is an electrical noise problem. I assume USB connection is stable while the printer is idle? Is it also stable if you pre-heat bed and nozzle and leave it for a while? The new board might be more susceptible to noise or generating more of it, try a shorter or better quality USB lead. Have you calibrated the motor drive currents? If they're higher than necessary this may generate a little more noise too.

Log in to reply