Prints keep getting offset layers. (Not machanical)

Jonathan9573

I am having an issue with my prints getting offset after 5-6 layers. Not always that way but that’s how it happens most of the time. So the prints will start out fine and layer are printing just fine the it’s almost like the machine will lose power for a split second then resume printing but everything will be offset by a quarter in or so. Kind of like it thinks the head is still moving but it actually wasn’t then the machanical part resumes were it think it should be.

Repetier

This is a printer side problem and no host problem.

Typical reasons are overheating of stepper drivers, cross talk to endstops from motors/heaters with end stop check always on, jerk/acceleration too high so you loose some steps and mechanical reasons are also possible even if you exclude them:-)

If it is always away from one endstop it is normally cross talk. If it is random direction it is one of the other reasons.

Jonathan9573

Ok. So how would I resolve the cross talk issue? If that is what it is? I have checked all motors and drivers and the heat under control. I have checked all parts for heat and everything registers ok. I have a fan blowing directly on the boards and keeping heat down.

Repetier

In repetier-firmware you could set ALWAYS_CHECK_ENDSTOPS 0 and if it goes away you know it is crosstalk.

Physically you would twist the cable for endstop and motors and heaters to reduce crosstalk. An additional shielding would also help, but maybe twisting would be enough. It happens if the cable are in close contact over some distance, then induction can cause signals being triggered.

Jonathan9573

Would it be an issue of the motor wires that are causing an issue and those would just need to shielded or would everything need shielding.

Repetier

IR cables should at least being twisted to prevent crosstalk and motor cables as well. But only if that is the problem and not reflections triggering ir probe as you guessed at the beginning.

Jonathan9573

So I have found the issue with the offset layers on my prints. For some reason the power supply turn on signal keep cutting out. I basically hardwired it “on” and now my prints are working just fine with no offset layers. Any idea on what might cause that?

Repetier

WHat firmware are you using? In latest repetier-firmware we have the option to disable power with timeout and turn it on on next move. But during print no timeout should be met.

Other reason is always crosstalk to PS_PIN. Have seen this happen when a pwm signal is close.