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Evidence Official manual formula + independent verification method Applies to Rotary-capable M2 and M3 configurations Safety Configuration change and controlled motion Updated 2026-08-21

Calculate rotary lead and restore the axes

The M-Series manual uses the relationship:

lead = π × measured workpiece diameter × applicable gear ratio

This expresses the surface travel associated with the configured rotary motion in the manual's setup. Its example shows a ratio of 26/48 for the demonstrated hardware. Do not assume that tooth count/ratio belongs to your rotary; inspect the supplied unit and use its documented values.

First-pass calculation

For a round part:

  1. Measure diameter at the actual processing band, preferably in several orientations.
  2. Compute circumference: π × diameter.
  3. Multiply by the gear ratio required by the specific Gweike rotary configuration.
  4. Enter the value only in the documented rotary lead/axis field after saving the original parameter.

Example of the calculation structure only: a measured diameter D with the manual-demonstrated ratio would use π × D × (26/48). This is not a default for all chucks or controllers.

Verify without laser output

Mark a fine reference line on the stationary part and fixture. Command the known rotary travel that should equal one circumference/revolution under the configured workflow. The mark should return to its reference without slip. Repeat in the same direction and then test reversal to expose backlash.

If a commanded circumferential length C produces a measured surface length M, a useful diagnostic correction relationship is:

new lead = current lead × C / M

Use it only after ruling out wrong units, diameter, ratio, axis mapping, and physical slip. Confirm the control's definition before changing a machine parameter.

Error patterns

  • Constant percentage error: diameter/lead/ratio or unit setting.
  • Correct at one band, wrong elsewhere: taper or changing effective diameter.
  • Different result on repeats: stock/chuck slip, coupling/mechanical issue, or measurement method.
  • Gap/overlap at a full-wrap seam: circumference mapping plus process start/stop behavior.
  • Wrong orientation only: axis direction/mapping, not lead.

Restore the flat-bed configuration

  1. Disable laser output and isolate energy for hardware changes.
  2. Remove/support work and disconnect the rotary only as documented.
  3. Reconnect the original axis hardware and inspect every cable/connector.
  4. Import or re-enter the dated known-good flat-bed backup—not values recalled from memory.
  5. With output disabled, verify axis identity, direction, home/reference behavior, travel limits, and displayed coordinates at reduced speed.
  6. Restore the CNC head/source/process mode and run FTC calibration.
  7. Simulate and frame a small flat test, then cut a measured coupon.

If an axis moves in an unexpected direction or distance, stop immediately. Do not swap wires or disable limits to make it home.