CNC Kitchen's open-source PrusaPATuner calibrates pressure advance on Prusa printers via load cell, no test print needed

Stefan Hermann of CNC Kitchen built PrusaPATuner, an open-source tool that calibrates pressure advance on Prusa printers using the nozzle load cell already fitted for bed probing. The tool taps Prusa's open Metrics interface, activated in the network menu, which streams the load cell signal to a companion app. It generates G-code that extrudes into free air while alternating slow and fast flow, then raises the K-value until the measured force undershoots the target level, taking the last value before that undershoot as the calibrated setting. Hermann reports results mostly on par with manually evaluated test patterns, with a larger deviation only for ASA printed hot.

Bambu Lab has automated pressure advance since the X1 via LiDAR and newer hotend sensors, but most other printer makers with comparable load-cell hardware have not shipped equivalent calibration software. PrusaPATuner shows that Prusa's open telemetry layer lets third-party developers close that gap without waiting on official firmware. Similar sensor-driven approaches are emerging elsewhere, including bd_pressure from PandaPi3D, the Amplify Hotend, and Snapmaker's U1. For Prusa owners, the practical effect is one less manual calibration print, delivered through community tooling rather than native firmware support.