I made some quick measurements to check if the cooling of the hotend is working properly.
The measurements were made during a long print with PETG when the temperatures were in a steady state. The thermocouple for measuring the heatsink-temperature was attached close to the lower edge of the heatsink, where you can expect the highest temperature.
First I made a measurement at room temperature, then I closed the heated housing of my printer and made measurements at elevated temperature.
Please note: Month ago I replaced the Noctua printer by a Sunon MF40100V1-G99-A for better cooling performance.
|Ambient temperature [°C]||Hotend temperature [°C]||Heatsink Temperature [°C]|
The thermal contact between the thermocouple and the heatsink is far away from perfect, thus the real temperature of the heatsink will be slightly higher than the measured temperature.
As expected, the cooling at room temperature works better than the cooling at high temperatures.
Because the extruderbody is made from PETG (continuous operating temperature ~65°C), I would not recommend to print large parts with hotend temperatures above 240°C with closed printer enclosure.