Rotary line interval calculator
Same chuck. Different tumbler. Calculate line intervals that match the available rotary step positions.
Enter your setup
Fixed for your motor, driver and gearing. Copy the correctly configured value from LightBurn.
Use the circumference entered in LightBurn’s Rotary Setup. Recalculate for each different size.
The interval you want to check or get close to.
Starts with example values. No printer connection required.
Closest whole-step interval
| Steps / line | Interval · mm | Approx. DPI |
|---|
Nearby mathematical matches—not guaranteed coating settings. Choose an interval that also suits your laser spot and test material.
Why the gaps can change
Illustrative nearest-step rounding, 24 gaps. Actual controller rounding can differ. This shows spacing, not predicted engraving colour.
The calculation, explained
Matching interval = surface movement per step × a positive whole number
Quick check = requested interval × Steps Per Rotation ÷ circumference
A whole-number result means the interval matches the commanded step grid. A fractional result requires position rounding. If the requested interval is smaller than one step, some requested lines can land on the same position.
The chuck’s step count stays fixed unless its hardware configuration changes. A different circumference changes surface travel per step. Do not alter Steps Per Rotation simply to make the maths work.
This checks one potential source of banding. Motor microsteps are not perfectly uniform, and alignment, movement, focus, residue and heat can still affect the finish. Displayed decimals are rounded; retain as many as LightBurn accepts. DPI is approximate—enter the interval in mm to preserve more precision.