Parts Fan staying off

[dspy8083 1]

Hello, I run Cura for my Ultimaker and my two CR10s printers.  I have encountered a new problem which I believe to be related to the slicer program.  I am seeking to run the part fan at 7% which displays on both my printers as this fan being on, however the fan is OFF!

Upon start of print, the part fan runs so I know it is functioning.  After the bed leveling stage and once it is about to lay the first layer of the brim, the fan turns off and stays off the entire print.  I have even set in the slicer for the fan to turn on at full speed at the initial layer, but is stays OFF.

 

Is there something in the settings elsewhere causing this issue?  Thanks very much!

Dan

[dspy8083 1]

[gr5 2,167]

So this problem is combination of three issues:

1) Fan will run at 7% but only if you "kick start" it.

2) Cura starts fan slowly from 0% to "full fan" (in your case 7%) gradually over several layers (typically first 5 layers).

3) Marlin firmware on CR10 kick starts fans but only when going from 0% to "on".  Not when going from 5% to 7% (it should kick start every time).  The kick start feature built into marlin puts the fan at 100% for maybe 1/10th second.

 

Please reread those 3 a few times until you understand the issue.  If you don't understand why those 3 things above cause the problem, maybe play with your fan in the menu.  Try going from 0% to 7% then try from 3% to 7%.  Big difference!

 

Okay so one fix is to change cura settings so that it goes to "full" fan in only 1 layer instead of 5 layers.  That's probably the simplest fix.  A better fix is probably to never go down to 7% - that's probably too low - try 30%.  What are you printing?  ABS?  Nylon?  If you are printing PLA you want it on 100%.  A 3rd fix would be for someone to fix Marlin so it does the kick start feature on every increase in fan speed (not just when it first turns on).

 

 

[gr5 2,167]

Another solution is to spin the fan by hand when it gets to layer 5 and once started it should keep going.

[dspy8083 1]

Thank you I will try this.

[dspy8083 1]

No luck, still does not work.

 

I will try another slicer.  

[dspy8083 1]

Excellent reply, thank you i appreciate your knowledge. 

I have made a few discoveries. 

1.  My CR10S S5 with the ufw marlin; fan will not run until approximately at 19%. Around 15% I could manually spin it and then it would run.  I may try a different fan  *I have a Meanwell supply turned up to 14v

2.  My CR10S PRO; my fault on that as on the touch screen display, the fan was set off 'X'.  

Both problems solved. 

Your suggestion to spin the fan prompted me to think turn up the %.

Thank you. 

And Cura, i will never think of cheating on you again!