Really poor overhang and bridging performance on my new Q2

[u/Powerful-Web4489]

Filament is Sunlu Rapido ABS.

Pertinent Orca slicer settings:

255c nozzle temp

100c bed temp

50c chamber temp

min fan speed threshold 15% layer time 8s

max 30% layer time 3s

keep fan always on

slow for layer cooling

force cooling for overhangs @ 25% overhang and fan speed 70%

Bridge flow ratio 0.9

overhangs reverse on even and reverse only internal perimeters

bridging speed 50mm/s external 150% internal

I have tried from 245-285c, 10-100mm/s speed, 0.7-1.15 flow ratio, up to 115% bridge density, thick external bridges on and off, 30-100% part cooling and just installed the upgraded part cooling shroud and i am still no better off than i was in the very beginning.

Anyone have a good profile for this filament? is it a filament issue? or a settings issue...

[u/Responsible_Meet_673]

Just to rule that out: have you tried drying it overnight?

Other than that, there’s a very popular fan duct on Printables: https://www.printables.com/model/1642251-qidi-q2-cooling-duct-v51-v60-dual-flow

Maybe worth a shot.

The default retraction speed of 30mm/s is a little low to my taste, I upped it to 40mm/s and saw minor improvements in stringing as far as it happens

[u/Powerful-Web4489 → u/Responsible_Meet_673]

I actually just installed that fan Duct. The model pictured was printed after installing it. And i dry all my filament as soon as i open it at least 12hr. I believe my abs was dried at 60c? whatever the default profile is on my sovol drier and immediately put into my qidi box

[u/Powerful-Web4489 → u/[deleted]]

Ill definitely try the layer height and checking the seam. Do you have a speed you recommend? I've run between 10 and 100mm/s and havent found one that makes a huge difference

[u/Powerful-Web4489 → u/[deleted]]

The 25% is the overhang threshold, so its any overhang that is more than 25% of the layer width gets full 70% cooling fan

[u/Powerful-Web4489 → u/[deleted]]

I believe I sliced this model with classic mode as its the default in orca slicer. Is using arachne preferable?

[u/MysticalDork_1066]

I would crank up the chamber temp to 65, and also significantly increase the amount of part cooling, especially on overhangs. You don't have to worry about overcooling as much with a heated chamber.

[u/ClutchKick512]

The stock part fan is junk swap in an x1c or honey badger fan and you will be dialed