Cura starts fan cool at L2 instead of L4

[Ch3vr0n 3]

Under "Cooling" i have the following settings

 

which to my understanding (regular fan speed at layer 4) means no part cooling until layer 4 (layers 1-3) starts. Under "Speed i have "Number of slow layers 4" (which equal my bottom layer count). Yet despite those settings, part cooling STILL KICKS IN at Layer 2 (albeit at a 33% according to octoprint) but the fan is visbily spinning. This is causing bed adhesion problems for me, despite using brim (and 3DLac). Am i missing something?

Advanced_Tool_Tray.3mf

[obewan 37]

If you mouse over the initial fan speed it explains that the fan is incremented from 'initial fan speed' upto 'regular fan speed' from layer 1 upto 'regular fan speed at layer'4

So to have no fan upto layer 4 you need to set 'regular fan speed' to 0

[Ch3vr0n 3]

Aha, so the first 3 lines should be 100/0/100?

[obewan 37]

1 hour ago, Ch3vr0n said:

Aha, so the first 3 lines should be 100/0/100?

I think thats right, all tho i have not tested it yet.

[Ch3vr0n 3]

yeah setting the first 3 lines to 100 (fan speed)/ 0 (regular) / 100 (Max) isn't it. That sets normal fan speed to 0 causing it to not kick in at all. Luckily i cought it in time after starting a 27h print. Manually flipped it on in octoprint.

[Ch3vr0n 3]

Anyone? Just tried again with a smaller item. A temp tower. Still engages cooling at layer 2 at full speed instead of the specified layer 4 (regular fan speed at layer: 4). If i go Fan speed: 100, regular fan speed: 0, maximum fan speed 100. The part cooling fan doesn't kick in at all no matter what layer. Not 2, not 4, not 5 or any higher)

TempTower_PLA_235-190.3mf

[tinkergnome 927]

On 7/29/2021 at 6:15 PM, Ch3vr0n said:

 

which to my understanding (regular fan speed at layer 4) means no part cooling until layer 4 (layers 1-3) starts. Under "Speed i have "Number of slow layers 4" (which equal my bottom layer count). Yet despite those settings, part cooling STILL KICKS IN at Layer 2 (albeit at a 33% according to octoprint) but the fan is visbily spinning. This is causing bed adhesion problems for me, despite using brim (and 3DLac). Am i missing something?

 

I think you can't achieve this with (only) the fan settings.

 

With the settings from above:

- Cura starts with "Initial Fan Speed" at the first layer, and this setting is used for the first layer only

- fan speed increases gradually on each subsequent layer until "regular Fan Speed" is reached at the layer that is configured as "Regular Fan Speed at Layer..."

 

It's well explained in the manual:

https://support.ultimaker.com/hc/en-us/articles/360012613199-Cooling-settings

 

You want to change the regular fan speed (or other settings) at a certain height? -> Use a mesh modifier. That's the only way at the moment as far as i know.

 

https://support.ultimaker.com/hc/en-us/articles/360013370140-How-to-adjust-print-settings-of-a-part-of-my-model-in-Ultimaker-Cura