G76: Lathe threading cycle
Automatic cycle for lathe threading.
For reference only: syntax changes with the control, the post-processor and the machine parameters. Check the official manual and run a simulation before cutting. Legal notice.
- Family
- Lathe cycles
- Machine
- Turning, Mill-turn
- Risk
- High
- Example
- G76 P020060 Q100 R0.05
G76 P020060 Q100 R0.05Parameters
- P (1er bloque)
- Seis dígitos PmmrrAA: mm = pasadas de acabado, rr = salida de rosca en décimas de paso (chaflán), AA = ángulo de la punta (60, 55, 30, 29, 00).Ejemplo P020060: 2 pasadas de acabado, salida 0, ángulo 60°.
- Q (1er bloque)
- Profundidad mínima de pasada. · µm sin punto decimal (Q100 = 0,1 mm)
- R (1er bloque)
- Creces para las pasadas de acabado. · mm
- X(U) Z(W)
- Diámetro de fondo de rosca (X) y final de la rosca en Z. · mm
- R (2º bloque)
- Conicidad: diferencia de radio entre inicio y fin (0 en roscas cilíndricas). · mm
- P (2º bloque)
- Altura del filete (profundidad total de rosca, en radio). · µm sin punto decimal (P1227 = 1,227 mm para M20×2,5)
- Q (2º bloque)
- Profundidad de la primera pasada; las siguientes van decreciendo. · µm sin punto decimal
- F
- Paso de la rosca (avance por vuelta). · mm
- Haas: K D A P I
- En Haas es un solo bloque: K altura de rosca, D primera pasada, A ángulo de punta, P método de penetración (1-4), I conicidad.Mismo ciclo, sintaxis distinta: no copiar un G76 Fanuc en una Haas sin adaptarlo.
Machine: Turning, Mill-turnRisk: High
Fanuc
G76 P... Q... R... / G76 X... Z... P... Q... F...- Very sensitive to the format and units of P/Q.
Haas
G76 X... Z... K... D... F...- Haas syntax may be different from classic Fanuc.
Siemens
CYCLE97/CYCLE99- Siemens uses specific threading cycles.
Fagor
Ciclos de roscado Fagor- Confirm parameters by manual.
Related:
Other codes in Lathe cycles
Frequently Asked Questions (FAQ)
What does G76 mean in a CNC program?
Automatic cycle for lathe threading. In the catalogue it appears as "Lathe threading cycle", within the Lathe cycles family.
How is G76 written on each control?
Fanuc: G76 P... Q... R... / G76 X... Z... P... Q... F... · Haas: G76 X... Z... K... D... F... · Siemens: CYCLE97/CYCLE99 · Fagor: Ciclos de roscado Fagor. The exact syntax depends on the control version and the machine parameters: always confirm with the manufacturer's manual.
Can you give me an example of G76?
G76 P020060 Q100 R0.05 — Automatic cycle for lathe threading.
Which other codes is G76 combined with?
In practice G76 appears alongside these codes: G32, G92. It is worth reading them together, because the state one leaves behind conditions what the next one does.
Which machines use G76?
G76 is used in: Turning, Mill-turn.
What should you watch out for with G76?
High risk: a mistake here can cause a crash, a broken tool or an out-of-tolerance part. Simulate the program and dry-run it before cutting.
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