Hot End Replacement with MaxTemp Overshoot

[Rich D]

I recently replaced my MeCreator2 Mk8 hot end for the second or third time (never an issue before). Now I have crazy overshoot and the temp goes WAY up really fast. I put my old one back in and heats fine.

After tons of research I found that the old mk8 extruder setup used a 30W heater and there is a "new" version that uses a 40W.

Have there been any firmware updates to handle this???? I can't be the only one who's noticed it. A friend of mine who bought spare hotends the same time as me connected his new ones after my issue and same thing, crazy overshoot.

Hoping for an answer besides having to purchase separate 30w heaters....

[William]

Hi，you can use M303 to change the PID and make the temperature stable.

[Rich D]

I spent 5 hours just trying to get the autotune to stabilize it and it wouldn't do it at a reasonable power to hold a stable temp. I had to turn down the max power value to 50 (0-255 scale) just to get autotune to not give me the "too hot" error from the overshoot. Then I programmed the new low power PID settings so I could start incrementally increasing the max power value back up (by about 10-15), rerunning the autotune, and input new value, repeat. I couldn't get it to run without getting too hot past a max power value of like 120 and it wouldn't hold a stable temp at 220C with the max power throttled back so far.

I ended up swapping the old heater over to the new hot end to make it work for now (back to working fine) But at least for me, simply running and messing with autotune was not helpful.