Junction Deviation & Jerk
Jerk (in classic Marlin firmware) and Junction Deviation (in modern smooth-path firmware) are kinematic motion-planning parameters that dictate the maximum allowable speed change at directional corners without coming to a complete stop.
Motion-planning settings trade speed against surface quality. Aggressive values lower machine hours; conservative values reduce reprint risk - the balance shows up directly in cost per part.
Estimate it in the 3D printing cost calculator →Jerk vs Junction Deviation Mechanics
Classic "Jerk" sets an instantaneous velocity jump threshold at angle transitions. Modern "Junction Deviation" calculates a smooth virtual corner radius based on the corner angle, acceleration limits, and centripetal force, allowing the toolhead to maintain smoother velocity profiles.
Tuning Corner Rounding vs Vibration Artifacts
Setting junction deviation too low forces the printer to brake to a crawl at every corner, drastically increasing total print time. Setting it too high induces severe mechanical shock, causing frame resonance, ghosting, or motor step loss.
Synergies with Pressure Advance & High-Speed Firmware
Properly tuned junction deviation works hand-in-hand with input shaping and pressure advance to ensure consistent extrusion line widths when decelerating into and accelerating out of tight corners.
Cite This Page
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APA 7
TryAR Labs. (2026, August 25). Junction Deviation & Jerk. MakerWorld Estimator. https://estimator.tryar.in/glossary/jerk-junction-deviationBibTeX
@misc{tryarlabs2026jerkjunctiondeviation,
title = {{Junction Deviation & Jerk}},
author = {{TryAR Labs}},
year = {2026},
month = {aug},
url = {https://estimator.tryar.in/glossary/jerk-junction-deviation},
note = {MakerWorld Estimator}
}Calculate 3D Print Costs in Real Time
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