Extruder Fan non spinning properly
I have a Geeetech A10 3D printer with Marlin 1.1.9. I hope you can help me.
I've recently decided to use Prusa Slicer 2.0.
I've noticed something "strange". When I launch a print, the fan on the heatsink of the hotend turns on and off even if I have set the cooling option on the filament tab so that the fan has to spin always at 100%.
I have tried printing with Cura (4.0 and 4.1) and the same fan is always spinning at 100% if I force the corresponding option.
This behaviour causes the filament to get stuck inside the hot end, because it softens and become fatter.
What do you think might be the cause?
[...] I've noticed something "strange". When I launch a print, the fan on the heatsink of the hotend turns on and off even if I have set the cooling option on the filament tab so that the fan has to spin always at 100%.
The setting under Filament Settings->Cooling->Enable keeps the part cooling (nozzle) on. It sounds like you're describing the hotend cooling fan which is normally on whenever the hotend is heated up. I don't know if you can manually control the hotend cooling fan with M106/M107. I would expect that fan to be turned on in firmware whenever the printer warms up. You might compare the gcode for a small print generated with Cura to one created with PrusaSlicer.
I wonder if the fans are simply reversed on your printer compared to Prusa's. If you connect via pronterface or other terminal, does M106 turn on either fan?
I tried to control the two fans via Pronterface as you suggested. It seems I can only controll the fan which cools the part with M106 and M107 gcodes.
The fan on the hotend heatsink is always on and I can't turn it off in any way.
I did a similar test using a gcode file saved on a SD card and the result is the same.
I read on RepRap that M106 P0 controls the default fan. I thought that the other fan could be P1 but it doesn't work either.
I've sliced a simple cube with Cura and PrusaSlicer. The gcode about the fan are the same. After the start gcode there is an M106 S255 on both.
I tried adding an explicit M106 S255 in the start gocde of the filament but the hotend fan turns on and off in cycles. (I can't attach the two gcodes).
Is there an option in PrusaSlicer to tell the software I have two separate fans installed?
Prusa Slicer 2, only controls the part cooling fan
the Original Prusa hot end fan is firmware controlled. it turns on above 50C and off below 50C
as far as I know, the Geeetech Hotend fan is permanently on, in firmware. You would have to change the firmware to change this functionality.
thaks for your answer.
So, if the hotend fan is firmware controlled, why the gcodes generated with Cura make the fan to stay always on, and the gcodes from PrusaSlicer cause that behaviour?
I think it's curious.
In fact, I had hard time trying to understand why the filament got stuck inside the hotend till I noticed the fan running on and off.