Help needed on layers printed with random patterns

[Smithy 1,144]

26 minutes ago, Andy6583 said:

I guess I will clean my computer off Cura and reinstall the old version that came with my printer (15.0.4... I checked)...

That's a good idea, then you will see if it is working with this version. Maybe the vendor of your printer as modified the Cura version in a special way that it is working, who knows...

[kmanstudios 1,120]

14 minutes ago, Smithy said:

That's a good idea, then you will see if it is working with this version. Maybe the vendor of your printer as modified the Cura version in a special way that it is working, who knows...

Most of the OEMS I have seen are versions of 1.5X.

[Andy6583 0]

Update....

Since I noticed the erratic movemets on the x- and y-axis, I replaced the stepper motors. 4 Euro each, no big deal.

I was successful right away. I printed one of my items just perfect. When I printed the second part (same file, same Settings !!!)

The problem came up once again in mid print... (see below...the one on top was printed immediatly after the replacement...)

What was different this time was that the movement was not erratic any more but the stepper of the filament feeder made strange toc-toc-noises. When I checked, I found that I could feel the filament frequently being retracted, as if the stepper receives a reverse pulse....

This was not the case when I made the first print !!! 

I checked with a third spare motor which immediatly worked without problems. I then tried the very first stepper I replaced once more. Same toc-toc-noise. So the motors I have used for printing both now have the problem, the spare left does not... 

 

Is it likely that the stepper drivers of the printer  somehow kill the steppers ?

I am not familiar with this type of motor...

Any ideas ? Do I have to replace the Mainboard of the printer ? What do you think ?

I would hate my last spare to be screwed just after a few minutes of printing...

Edited December 8, 2018 by Andy6583

[P3D 46]

Hm, that sounds really bad! Does your mainboard have replaceable stepper drivers, or are they soldered?

[Andy6583 0]

update...

I read some posts in other forums that also mentioned the Toc-Toc in the feeder stepper motor. Many reasons were given, ranging from -once again- blocked nozzles to reduced current for the stepper to overheated filament sensors... With curious "cures" from printing PLA @265° or drilling through the tubes down to the nozzle with a 2mm drill....

 

Since my Malyan has no filament sensor to overheat, I replaced the complete extruder unit including stepper (forgot to mention that in my last post...did not just replace the stepper !), checked the whole of the filament transport and found no problem, since the other replacement unit (not used to print as yet)  does not make any Toc-Tocs when I hook it up to try...

I guess that something happened to the driver circuit that destroys the stepper... The steppers that once showed that problem do continue to do so, no matter what. Even with no filament inserted... whereas my last replacement unit does not yet. And I do not want to waste that before I know the cause...

 

Since the replacement unit showing the problem was just ordered from Hobbyking, I took the opportunity to issue a claim describing the whole thing. Maybe they have some information on the topic  and hopefully provide a solution...

 

I hope to find a solution soon, because I desperately need to print :-((

 

I will keep you posted...

 

@P3D... no, unfortunately it has not... I would have to replace the mainboard which is about twice the prize of the whole extruder assembly...

 

 

Edited December 10, 2018 by Andy6583

[Andy6583 0]

p.s.:

 

[Andy6583 0]

pps.: this is the replacement mainboard they offer over @Hobbyking for ~40€...

 

I may need to buy that one, too...

[geert_2 557]

That toc-toc sound might also come from the nozzle being blocked, so the filament can not move, or not enough, and the stepper skips steps? Or it could be a build-in protection, to prevent the feeder from grinding the filament in case of a blocked nozzle. The old UM2 also has this feature, and when the nozzle is blocked, or you try to extrude too much material too fast, it also makes this sound while the feeder steps back. I am not saying that this is the case in your printer (I don't know that model), but it might be worth looking into, just as another option on the list?

 

[Andy6583 0]

wish it was that simple.... the one thing I am pretty sure of is that the nozzle is NOT blocked (see above)...

and moreover, it can´t be a problem with the filament transport because the steppers do that noise even after I have disassembled the extruder unit and let the steppers run free... they briefly change direction...

 

 

[geert_2 557]

21 hours ago, Andy6583 said:

wish it was that simple.... the one thing I am pretty sure of is that the nozzle is NOT blocked (see above)...

and moreover, it can´t be a problem with the filament transport because the steppers do that noise even after I have disassembled the extruder unit and let the steppers run free... they briefly change direction...

 

 

Ah okee, I see. Yes, then it rather looks like a problem in the motors, wires, or drivers indeed. But that is out of my experience...