drastic extruder temp drop after first layer
This has historically never been an issue but I first noticed this after flashing the 3.7.1 firmware (I was previously running the 3.7.1 rc1 and this was not an issue). I use the MK3 kit (upgraded to MK3S), prusament filament, the new PrusaSlicer and their OEM slicer profiles. The slicers default setup for PLA is 215 degrees on the first layer and 210 on the rest.
When my printer finishes the first layer and the cooling fan kicks on, the extruder temp will quickly drop to the 190s (and before PID tuning, it would drop into the upper 180s) before it starts to warm back up. Usually this causes the extruder to skip and ruins the print. Even if you change the slicer for ALL layers to be the same temp (215), the temperature still drops significantly before warming back up (even though it should have never changed at all).
I had reflashed the 3.7.1-rc1 firmware as a test but the problem still persists. As a bandaide I've been setting my first layer to print at 225 and the rest of the layers at 215 so even if the temperature drastically drops, it's still within the safe extrusion range. Any tips on troubleshooting this? All I've done is the PID tuning.
I have a short video showing this at:
RE: drastic extruder temp drop after first layer
After some research, I do have a silicone sock (just not installed). When the current print finishes i'll put the sock on and see if that fixes the issue, next I'll lower the max cooling fan speed and see what that does.
RE: drastic extruder temp drop after first layer
okay so after installing the sock, a print that had a first layer temp of 220 and subsequent layer temp of 210, the temp dropped down to 206 before climbing back up to 210. I think this is more reasonable and maybe a slight tweak of the max fan speed will make it better.
RE: drastic extruder temp drop after first layer
I'm going to bet heater cartridge is dying, but would be worth rechecking its wiring at EINSY connector plug.
RE: drastic extruder temp drop after first layer
You'll need to do a PID tune after installing the sock as the heater's thermal characteristics have changed.
RE: drastic extruder temp drop after first layer
Check to make sure the metal portion of your thermistor is not exposed on either end. I had this problem when I did the “S” upgrade. I replaced my thermistor, but suspect the new fan duct configuration was blowing air where it didn’t in the past.