broken cables extruder assembly
I have a Prusa I3Mk2. I am suspecting that some of the cables to the print-head are worn out / broken.
The symptoms are that on some prints at about 120mm height the extrusion becomes erratic and the print fails in such a way that the printer continues to move but layers are underextruded, then there might be some layers stuck together well and again more underextruded layers. The problem is that this happens on very long prints and I have experienced it a few times but never been watching it (woke up in the morning and seen it) So I did a test object with thin walls (to save filament) but it printed just fine.
Another issue is that the print cooling fan (front) stopped working and it seems to be related to its cable because sometimes when the carriage is at the extreme left or right side it comes on momentarily. So I think this is clear, cables broken.
But I don't love tinkering with my printer so much that I want to take it apart many times. I am thinking that the cables are probably not broken near the ends so perhaps I could solder new ones into place. There are quite a few of them, extruder motor, 2 fans, heater cartridge, thermistor, pinda probe. I wish I could just order a new cable kit! But I think its not possible with the Prusa I3Mk2 because most of the cables are fixed permanently to the respective components. (I wish serviceability would be easier with the Prusa I3Mk2!) So does someone have experience which ones of the cables usually fail and which kind of cable could be used in a kind of "re solder" project ? I am looking for a cable which does not cause any new problems by being to inflexible or causing some kind of electromagnetic interference.
Which are the extruder assy cables mostly / usually failing and which would be a nice quality cable to replace these?
I know it is unfortunate that I can not reproduce the situation with the underextrusion while watching the printer but I really don't have the time to babysit it for so many hours. That's why I am ready to replace some cables pro-actively even though they might not be broken now. I need my printer to perform reliably. Some might understand...
thanks for sharing thoughts and experiences on this.
BR,
Chris
RE: broken cables extruder assembly
The most common? From everything I've read, it's pretty random. But any wire can fail. I've read about fans, pindas, heaters, thermistors... oddly, never read about a filament sensor wire breaking.
But if you've got intermittent fans and heater, then probably a good time to replace all the cabling. And if you can, find where the wires are breaking and determine if they are all breaking at the same place: if so, then look into ways of adding strain relief at that spot.