PA with Large Nozzles (0.8 and 1.2mm)? any suggest

Hello everyone.
I need to print with very large nozzles, to print resistant pieces and to drastically reduce the production time.

I switched to Hemera extruder with Volcano, BrozzL and X nozzles, 0.8 and 1.2mm.

Now I have problems with heavy oozing in small part fills and on overlap (infill-perimeters).
This extruder (whit no PA), needs a very small retraction (0.40 / 0.60), if i go further, holes are formed in the seams. To improve the oozing problem I wanted to set the PA correctly as in the other printers with klipper that I usually use (standard 0.4 and 0.6 nozzle), but with 0.8 and 1.2mm I cannot push the printer at the speeds required by the Tower Test (100mms).

Any advice on which speed to use for the test?
Will PA be really useful with such large nozzles?

Sorry for my bad english.

Thanks

The PA tuning tower has to be printed at a realistic flow rate, higher than for normal printing, but bellow the hotend limit.

If you slow down the print speed, I’d suggest to adjust the acceleration. Otherwise, the areas that should have defects, where the toolhead accelerates and decelerates, could be too small.

With the recommended print speed=100 mm/s and max_accel=500 mm/s², the toolhead accelerates (and decelerates) over a distance of 10mm : d = speed^2 / (2 * accel) = (100 mm/s)^2 / (2 * 500 mm/s²) = 10mm

So, In order to keep the acc/decelerating segment lengths constant, you may set ACCEL = speed^2 / (2 * 10mm)
For example, with a print speed halved to 50mm/s, use a quarter of the recommended acceleration: ACCEL = 125 mm/s²

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Thanks you so much mate, i will test tomorrow.
:muscle:

Mate i have test it, and WORKING VERY VERY GOOD at moment.
Now i can print whit 0.8 Nozzle, 0.85 Layer Width, 0.6 Layer Height, 50mms speed, 800 Accel, 5 Square Corner, with 28/35mm^3/s flow.
I have test PA with 60mms speed and 150mm/s Accel.

Perfect Seams and good corner for 0.8 nozzle.

Thx you so much

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