material cooling fan, bug issue?
I just noticed through testing that if you start with the cooling fan turned off then raise to say 5% the fan will not kick over.
it seems the fan needs a kick start I had to raise the fan over 10% manually and I could see the fan was attempting to turn over so i flicked it by hand and it started spinning I then brought the fan cooling back down to 12-13 for 5% cooling.
i thought i was going nuts i Kept checking my Gcode over and i had the correct M106 S12.75 code.
I seems like you have to add a
M106 S25.5 or higher
then possibly a G4 delay command and then,
M106 S12.75 to force the fan to start up and get past initial friction and fire then bring the speed back down.
this would explain some failures i had when i walked away from the machine i assumed the cooling was working at low settings but it might not of been.
anyone else notice this? is this a known issue?
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Re: material cooling fan, bug issue?
Never tried it, but sounds completely normal to me and nothing you can fix in an easy and controllable or generic way (unless you monitor fan speed).
Keep in mind the required initial momentum to get it running might not only depend on the actual fan motor (not just its design but also the current rotor position), but also whether and how the case is squished by tightened screws etc.
Also if the firmware is told to spin the fan at x%, it can't just spin at x+10% and then slow down again, so (to me) the only reasonable approach is to indeed do that manual kick start in the code.