ASA Profile settings for Hemera Direct Drive

[CRAK 0]

Hi,

 

I'm running a Creality Ender 5 Pro, upgraded with a Hemera Direct Drive (incl. a 32 bit Creality board and custom Marlin 2 firmware).

Results for PLA, PETG, Ninjaflex and PA12+CF15 filament are great.

My current struggle is with ASA though (Filamentum ASA Extrafill "Traffic Yellow"): I can't find the proper settings for a profile (Cura 5.2.1).

 

I have tried a temperature tower from https://www.thingiverse.com/thing:4979115 (260 to 230C) on a 110C bed, 0.2mm layer height and 0.8mm retraction at 40mm/s.

The print speed is 40mm/s (4 slow layers), layer height 0.2mm, line width 0.4mm (using 0.4mm E3D Nozzle X for 1.75mm).

Cooling is off, coasting is off, fuzzy skin is off, bridging is on (min. length 2.2mm, 10mm/s, 50% - 60% flow, bridge fan speed 100%.

While printing, the printer is kept in a Creality flexible enclusure with no additional heating.

 

You'll agree from the attached photo that this was quite crappy. The 2 little pinnacles on each floor are ok, but the surface and bridging are nowehere near acceptable.

First I assumed wet filament. My Sunlu Filament Dryer S2 ran for (>6) hours @ 70C before I tried again, but there was no obvious improvement.

 

I then lowered the same tower 50mm (keeping only the top 2 floors for faster testing), enabled the draft shield and fiddled around with different retraction settings.

With the temperature set to 250C (fixed) I'm now down to 0.5mm retraction @ 25mm/s without even the slightest improvement (I may have missed the sweet spot along the way and haven't increased e.g. retraction distance yet).

 

Does anyone recognise the rough surface and knows how to prevent it?

Does anyone have a profile to share that offers better results?