Max Acceleration / Velocity

Maximum safe speed and acceleration limits — the fastest the printer can move without skipping steps, losing accuracy, or causing artifacts.

What It Is

Maximum acceleration and velocity define the speed limits for the printer’s motion system. Set too low, prints are unnecessarily slow. Set too high, the motors skip steps, belts slip, or vibration causes quality loss.

What It Controls

Print speed (total print time)
Motor reliability (skipping steps = layer shifts)
Print quality at speed (higher accel = more vibration)
Travel move speed

Why It Drifts

Belt tension changes affect max reliable acceleration
Motor driver current settings change
Added toolhead mass (heavier = lower safe acceleration)
Stepper motor heating (hot motors lose torque)

How to Calibrate (Manual)

Start with conservative values (e.g., 3000 mm/s² accel, 300 mm/s velocity)
Increase acceleration in steps, print test objects
Watch for layer shifts, skipped steps, or quality degradation
Find the maximum values that produce clean prints
Set limits in firmware with safety margin (~80% of max)

How the Auto-Tuner Calibrates It

Accelerometer detects vibration amplitude at increasing speeds
Sensorless homing stall detection identifies when motors approach skip threshold
Systematically finds safe limits without trial-and-error prints