not Printing after upgrade
Hi,
I purchased the Upgradekit from MK2 to MK2.5 recently and assembled the Printer, following by the Manual.
When I start a testprint, the Extruder starts clicking after a while and isn't able to load filament anymore.
This happens randomly.
I am printing in PLA with the supplied settings from prusa. Slicers: S3D,PrusaControl,Slicr(prusa edition)
If the print passes the first layer, the Fan starts and cools the Nozzle so much ( about 10-15 degres), that the extruder again starts clicking, because of the too low temperature, and finally runs into a Thermal runaway.
I have seen in the Tune-Menue that the Fan is at 250+. The nozzle should be at 210 degrees, but because of the high Fan-speed, it's under 190 degres!
The Printobjects I have tried were the supplied Gcodes from Prusa (Marvin , Prusalogo).
If I lower the Fan-speed manually to about 100 it won't start clicking and the temperature is stable at 210 degrees.
I did a chat several times with the Prusa-support but none of the suggestions helped 🙁
I tried following suggestions:
Cleaning and finally changing the Nozzle (it might be clogged )
changing the PTFE-Tube ( I pushed it all the way down into the heatbreak )
Cold-pull
checking the shroud if it sits correct
changing the Filaments
By the way: Before upgrading, the Printer worked perfectly smooth without any problems.
The Firmware is: 3.2.1
No I'm asking you for help. Maybe someone could give me a clou with this problems. I'm really disappointed right now that it won't work...
Thanks in advance
Ralph
Re: not Printing after upgrade
Good afternoon Ralph,
Could you show us some pictures of the printer,
especially the area where the extruder cold end heatsink is located in the extruder housing, and where the part fan blows onto the nozzle area?
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: not Printing after upgrade
Hi,
I hope the pictures are what you want. Otherwise I will shoot another one.
Re: not Printing after upgrade
Following this post as ive upgraded mine today and have the exact same problem.
The fan is cooling the hotend too much that it causes thermal runaway. I have to decrease the fan speed for it to print.
Re: not Printing after upgrade
It's definitely the fan shroud. it's garbage compared to the original. you could just try a different design by someone else or put a e3d sock on it....
Re: not Printing after upgrade
I have never had thermal runaway issues on my Prusa printers but I had them with my Prusa clone running on Marlin firmware. The problem was always the same : bad or loose wiring.
The first thing I will carefully check all extruder and power cables for possible problems. If no issues there, I will run PID configuration. Right now I do not have access to my printers, so I will give you some general approach. If somebody else could fill the gasps that will be great.
First, I will record the current PID configuration (there are 3 values), next run PID configuration without actual commit. Compare the values. You can also run PID configuration with fan on. As long you recorded the initial values, you can always try to print with other configuations and come back.
Anyway, If you change fan shroud or put the silicon sock you will need to run PID configuration again.
Re: not Printing after upgrade
Hi Ralf,
is your cold end heatsink level with the bottom of the housing? like this! ?
if the Cold end heatsink is sticking out of the housing, something is wrong with your setup and the heat block will be getting too much cooling.
and the heat break will be getting insufficient cooling!
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: not Printing after upgrade
I had a similar problem some months ago with a thermal runaway.
My guess is, that its not the fan cooling too much, rather than a broken wire from the thermistor.
Wire up your multimeter and move the cable around. if there is a cable break you should recognice it.
Re: not Printing after upgrade
Hi everyone,
sorry for not answering immediately.
It was a busy week (too much Football Games to See 😀 )
It's definitely the fan shroud. it's garbage compared to the original. you could just try a different design by someone else or put a e3d sock on it....
Thanks Eric for your Suggestion. I have ordered a silicone sock from e3d and tried it today.
It ist a great improvement for the temperature stability.
I have printed the Marvin Testfile, and the temperature was stable at 215° +-1°C, even when the Fan is cooling at full Power.
After the first testprint, i've tried another one. Temperature keeps stable, so far so good. Until the Extruder starts clicking again. 👿
I've stopped the print, set the nozzle temperature to 215°C and tried to extrude some Material manually (direct after the print)
Surprisingly the Extruder didnt start clicking and extruded the Filament perfectly.
My Question: how could this happened?
I unloaded the Filament after the clicking, but the Extruder couldnt pull out the Filament, so i have to pull it by hand, which was very hard to do. Here you can see how the Filament looks like after the pull:
It is slightly thicker than the Rest of the Filament.
What so you think?
Re: not Printing after upgrade
Here is the failed testprint. You can see, that somehow a litle bit of Filament is extruded.