Sudden MAX_THERMAL shutdown on MK3S+
I've been using my factory assembled MK3S+ for several months now with excellent results, and have close to 1000 hours printing time on the machine. I've been doing the 200 hour regular maintenance all along. I print only PLA with the standard profile. This past week I started noticing that the hot end temperature was taking higher and higher excursions before settling down to 215 C. Yesterday I started a print, and while the first layer was going down the temp suddenly spiked to 260 C and the machine gave a MAX_THERMAL error and stopped the print.
I cycled the power and let the fans cool everything down.
How should I troubleshoot this. I don't see anything out of the ordinary around the nozzle.
Has anyone come across these symptoms? Any guidance would be much appreciated.
Thanks
Mike
RE: Sudden MAX_THERMAL shutdown on MK3S+
Check the wire connectors into the Einsy board.
May be time replace thermistor/heater element.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: Sudden MAX_THERMAL shutdown on MK3S+
Thanks I will check those both out.
Where can I get parts if need be? Also, what about nozzles - is there a source for those or will any generic Reprap nozzle work?
Thanks
Mike
RE: Sudden MAX_THERMAL shutdown on MK3S+
Printedsolid sells genuine Prusa parts. But any generic E3D part will do. The Prusa parts have the right wire length and connectors. Other parts may or may not. Look for "compatible with Mk3 S".
Nozzles. Any E3D v6 nozzle will work.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: Sudden MAX_THERMAL shutdown on MK3S+
Thanks I will take a look
Best regards
Mike
RE: Sudden MAX_THERMAL shutdown on MK3S+
Some updates on this: After doing some more reading, I checked the tightness of the grub screw holding the thermistor. It wasn't tight, so I snugged it up. Tried another print, and although the hot end pre-heated okay, once printing started I saw the temperature readings jumping around nonsensically - 150, 230, 180, etc. every second. Print wasn't sticking either so I suspect the actual temp wasn't what it should be.
Based on this does sound like I should just replace the thermistor, or should I replace the whole hot end assembly?
The cost difference isn't really a factor, and it looks like about the same amount of work either way. I would rather do the repair only once, this is my main production printer and downtime is a big factor.
Thanks for any advice
Best regards
Mike
RE: Sudden MAX_THERMAL shutdown on MK3S+
Hi Mike,
I would buy a hotend, and a thermistor,
then I would try replacing the thermistor, if it works, you have a spare hot end for next time...
If it doesn't work, you have a replacement hot end for Now...
another option, is to consider replacing the wires between the thermistor and the einsy, making solder joints on the extruder assembly and inside the einsy box, insulating them with heat shrink sleeving, if available, otherwise any sleeving... (as long as the joint near the extruder is not too near to the heat block)
and try the printer...
I have just done that on my Mk3 printer heatbed thermistor... and the printer is working fine
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
RE: Sudden MAX_THERMAL shutdown on MK3S+
Yes I think that is a good approach. I'm going to do a little more checking to make sure it isn't a wiring issue, then order the replacements.
Thanks
Mike
RE: Sudden MAX_THERMAL shutdown on MK3S+
Might be worthwhile buying a heatbed thermistor at the same time, so you have a spare if that goes faulty,,, they don't cost a lot, but delivery can make them appear expensive if ordered on a later date.
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
RE: Sudden MAX_THERMAL shutdown on MK3S+
I saw that many parts were out of stock so I jumped on the complete hot end while it is still available. You have a good point though, and I'm going to watch PrintedSolid and pick up some spare bits when they come back in stock.
I also have some inexpensive clone machines, and keep bucket loads of spare bits as something is always going bad on those.
Best regards
Mike