G32 / G33 Zigzag Threading Calculator and Simulation
Without using G76, it produces every pass as explicit NC blocks. On rough passes it alternates the load between the right and left flank; finish passes run on the center. Calculations run in the browser and no data is sent to a server.
1. Operation Details
2. Straight / Taper Thread
3. Material and Speed
Advanced pass and safety settings
Calculation Results
Geometric Simulation
This simulation shows the geometric tool path. Servo acceleration, spindle phase error, tool deflection, real chip breaking and collision physics are not calculated.
Pass Table
| P | Flank | X start | X end | Z start | Z end | Radial pass | Cum. depth | Q |
|---|---|---|---|---|---|---|---|---|
| No calculation yet. | ||||||||
Generated NC Code
What Is G32 / G33 Zigzag (Alternating Flank) Threading?
Zigzag threading feeds the tool alternately into the right and left flank with a small Z shift on each pass, reducing the double-edge load and vibration of radial plunge. It improves chip control on large-lead (trapezoidal, ACME, coarse metric) and deep-profile threads. On FANUC lathe controls the basic synchronous threading command is G32 (or G33 in some code systems); every pass and flank path is written by the program. This tool produces the pass distribution, flank Z offsets, ready NC code and a 2D tool-path simulation.
Frequently Asked Questions
What should the feed (F) be in zigzag threading?
The F value is the thread lead: single start F = pitch, multi-start F = pitch × number of starts. For example, a 3 mm pitch double-start thread uses F6.
What is the difference between G32 and G33?
Both are constant-lead synchronous threading commands; which one is valid depends on the machine FANUC code system. Verify the control G-code list before use.
When is the zigzag (alternating flank) method preferred?
For large lead, wide profile, long threads, stainless/sticky materials and vibration risk, alternating flank infeed gives more stable results than radial plunge.
How are the start angles set for a multi-start thread?
On FANUC each start is cut with a different Q start angle: double start Q0/Q180000, three starts Q0/Q120000/Q240000. The tool inserts these angles into the code.
This G32/G33 zigzag (alternating flank) threading calculator and simulator generates the spindle speed, feed (F=lead), pass distribution, flank Z offsets and ready FANUC NC code from the thread type, pitch, diameters and material, and shows the workpiece, insert and tool path in a 2D simulation. For standard thread calculation, see our Thread Calculator and NC Program Generator.