Pressure Advance is a firmware feature that compensates for filament elasticity and flow dynamics within the hotend. Properly tuning Pressure Advance improves print quality, particularly regarding sharp corners and the appearance of the print seam.
This guide explains how to understand, adjust, and calibrate the Pressure Advance setting for your 22 IDEX using PrusaSlicer. The goal is to fine-tune extrusion behavior to achieve sharper corners and minimize seam artifacts (bulging or gaps). While we provide well-tested default values in our PrusaSlicer profiles (optimized for a 0.4 mm nozzle), factors like nozzle diameter and filament moisture content can necessitate adjustments for optimal results.
At its core, you can think of Pressure Advance as a smart way the printer adjusts filament flow just before speed changes, somewhat like dynamically altering retraction during a print move.
20mm cube .stl) ready.Warning: The printer's nozzle and bed can reach high temperatures. Avoid touching hot components during operation.
Pressure Advance primarily affects two visual aspects of your print:
- Corners: Properly tuned Pressure Advance results in sharp, well-defined corners. If corners are rounded, Pressure Advance might be too high. If corners have excessive bulging or overshoot, it might be too low.
- Seam: The seam is where the printer starts and stops extrusion on each layer.
- If the seam bulges outward significantly from the print surface, Pressure Advance is likely too low (or off), causing excess pressure release at the layer end.
- If there is a gap or depression at the seam, Pressure Advance might be too high, retracting too aggressively before the layer change.
The Pressure Advance value is set via custom G-code within the filament profile:
M572 D0:1 S0.035. This command sets the Pressure Advance value. If the line is not present, the printer will use its firmware default or none if not configured.Our default profiles often use a Pressure Advance value suitable for common materials with a 0.4 mm nozzle.
Default (0.4 mm Nozzle): A typical starting value for many plastics (like PLA, ABS) is S0.035.
Larger Nozzles (0.6 mm): Pressure effects are less pronounced with larger orifices. You should decrease the Pressure Advance value significantly. Try starting around S0.01 or even disabling it completely by setting it to S0.0.
Very Large Nozzles (0.8 mm and up): It is generally recommended to disable Pressure Advance entirely for very large nozzles set to S0.0.
Important: To disable Pressure Advance, you must explicitly set the value to zero using the G-code command:
M572 S0.0
Simply deleting theM572line from the custom G-code will cause the printer to revert to its built-in firmware default (which might be0.035or another non-zero value), not disable it.
S value slightly (e.g., from 0.035 to 0.045).S value (e.g., from 0.035 to 0.010, or from 0.01 to 0.0 for larger nozzles).M572 S<value> in the filament's start G-code, re-slice, and print again.Tip: Use a calibration model for Pressure Advance tuning (like a Cylinder or Square) for faster iteration.
M572 line, but Pressure Advance still seems active?
M572 S0.0 in the filament's start G-code.Fine-tuning Pressure Advance is a key step towards achieving high-quality prints, especially those with sharp geometric features. Remember to save your tuned settings as a new filament profile in PrusaSlicer for future use. Performing a test print with a model representative of your typical prints is recommended to confirm the calibration.