Temperature issues with my MeCreator 2

[txm_butch]

Hi There,

I am fairly experienced with 3D printers and am having some issues with trying to get my MeCreator 2 to reach a steady temperature. The printer says I can reach 240 degrees without any issue but I am just not able to reach it stably. I am running the latest version of marlin and have tried PID tuning (M303) with no luck as it only causes oscillations. I also can notice how the temperate is varies a lot, going from 240 down to 235 within 2 seconds etc. Here is a screenshot of the printer heating up to 240 deg:



And here are the current PID settings:



Hope someone could help me work out this issue.

[William]

Hi，poor contact may cause unstable temperature, you can check the wiring. If the connection is good, you can adjust the PID, refer to this link: https://reprap.org/wiki/PID_Tuning.

[txm_butch]

Hi There,

I have just checked the wiring at the breakout board and reseated at thermistor connect or and stripped the heater cartridge wire with no success it seems. I also looked at the heater block to find any damage but both the thermistor wires and heater cartridge wire seemed to be intact. I still ran PID autotuning using M303 but increased the temperature to 230 deg as I usually print at this temperature. But still, I had no success. The image below shows PID tuning with 10 cycles and then heating the bed to 75 degrees and hot end to 230:



Is there any way to fix this issue in the firmware maybe?

I really like this printer by the way. Its been a workhorse.

[txm_butch]

UPDATE:

I've just pulled the thermistor out of my heater block and noticed how the rubber tube was covering the thermistor itself. I've just stripped it back to expose the sensor itself and I am now able to maintain a stable temperature. Seems that the tubing was acting as an insulator from the thermistor itself.

[William]

Solve it? I am happy for you!