K1 Max bad print surface quality after hotend replacement

[heike]

Hello,

maybe I’ll be lucky and someone here can help me out.

I own a K1 Max and was actually quite satisfied with the print results. Even large letters at 30 cm height had an almost completely smooth surface.

Then unfortunately it happened and I had to replace the hotend including the nozzle. I purchased the Creality K1 Max Hotend Upgrade Kit (ceramic heater block & quick-swap nozzle for 600 mm/s & 300°C high-temperature printing), since I had already been using it before.

Of course, I then checked and recalibrated bed leveling, Z-offset, and all other calibrations. Nevertheless, even with the help of AI, I can’t get anywhere near the same quality results anymore. Attached is one image without ironing and one with ironing. Do you perhaps have any ideas on how I can achieve good results again?

And here are my configurations:

Wall loops = 2
Top shell layers = 6
Top surface density = 100%
Top surface pattern = Monotonic
Bottom shell layers = 3
Bottom surface density = 100%
Bottom surface pattern = Monotonic
Top/Bottom solid infill/wall overlap = 25%
Sparse infill density = 25%
Internal solid infill pattern = Gyroid
Solid infill direction = 45°
Top surface speed = 25 mm/s
Outer wall = 1200 mm/s²
First layer = 500 mm/s²
Top surface = 300 mm/s²
Part cooling fan = 70%
Auxiliary part cooling fan = 20%
Keep fan always on = ON
Slow printing down for better layer cooling = ON
Flow ratio = 0.92 ← after calibration

Thank you!!

Heike

[Ben_Engelen]

To me this seems like under extrusion.
Could it be that the temperature of the hotend is not stable, or the flow ratio is somehow not correct after the calibration?

[heike]

Thank you very much for your reply!

Unfortunately, Inoticed that the bed levelling was not displayed correclty and so the bed mesh was very poor.
I have now corrected this, and the prints look good again.

But thank you for your effort!