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Min layer time/ Fan speed threshold/min speed issue


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Posted (edited) · Min layer time/ Fan speed threshold/min speed issue


So I brought a simple cone shape into cura to test how cura increases fan speed for shorter layer times. I had my min layer time set (MLT) to 10, my fan speed threshold (FST) set to 18, and my min speed set to 10. The cone was sliced into 200 layers. I looked at the gcode file and the fan reached maximum speed at layer 92, not at the very top layer like I hoped it would (and because lift head is off, the layer times will go below 10 seconds). I figured out that if I set MLT to 0.001 the fan would reach max speed at the very top layer. The problem with this, however, is that the printer will never slow down for short layer times. Cura doesn't seem to consider the fact that the printer won't actually be obeying the MLT when lift head is off. Is there any way I can get the best of both worlds; the fan speed tapering under MLT and slower print speeds under MLT?



Edited by osterac
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    Posted · Min layer time/ Fan speed threshold/min speed issue

    Maybe I didn't do the best job of explaining. All the settings I'm talking about are in the cooling section. When min layer time is set to 10 seconds and min layer speed is set to 10mm/s, if the layer time drops below 10 seconds the print speed will be reduced in order to raise the layer time to at least 10 seconds (but not below a speed of 10mm/s). Say you are printing at 30mm/s and the min layer time is 10 seconds and the min layer speed is 10mm/s. if the layer time is 3 seconds, the printer would have to slow down to 9mm/s in order to do a 10 second layer. However, it can't because the min layer speed is 10mm/s. If lift head is on, at the end of the layer, the printer will lift the print head 3mm and pause for 1 second to meet the min layer time requirement. The drawback to this is oozing filament that sticks to the print. If lift head is off, the printer will ignore the min layer time and print the layer in 9 seconds (as slow as it is allowed). However, the fan speed won't be increased to compensate. I don't know if a setting for this is already there, but if not, it would be great to have.


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    Posted · Min layer time/ Fan speed threshold/min speed issue

    Sorry for posting again, but I wonder why no one is answering? Did I post in the wrong section? Even if you don't have an answer, maybe just to say it can't be done, I would appreciate a response.


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