Printed from Kezuriba (kezuriba.net/en/nc/g97/)

G97

Machining center, LatheModal, group 13

Constant surface speed control cancel (constant spindle speed)

⌨On machining centers

G97 S_ (min⁻¹)

S returns to spindle speed (min⁻¹). Power-on default (Siemens ISO)
For threading and drilling (near the center), fixing the speed with G97 is the basic practice

Diagram: Diameter and spindle speed: constant surface speed (G96) and constant rpm (G97)

In G97, S is the spindle speed itself and stays constant regardless of diameter. Threading and drilling near the center should basically use a fixed spindle speed. The green line is for G96 (constant surface speed).

◎On lathes: Constant surface speed control cancel

The same number means something different on lathes (FANUC-type G-code system A). Group 02.

≠Differences between controls and machines

The same code can be written or assigned differently depending on the CNC control and the machine builder. Always check your machine’s manual.

Source	Machine	Item	Detail
Haas	Lathe	Group	13

📚Sources

The meaning shown agrees in at least two sources (one source only, for reference). Explanations are written in our own words.

Siemens AG — SINUMERIK 802D sl/840D/840D sl/840Di/840Di sl/810D Programming Manual ISO Milling, 04.2007 Edition (6FC5398-7BP10-0BA0) cache.industry.siemens.com
Siemens AG — SINUMERIK 802D sl/840D/840D sl/840Di/840Di sl/810D Programming Manual ISO Turning, 04.2007 Edition cache.industry.siemens.com
Haas Automation, Inc. — Lathe Operator's Manual – 16 Lathe G-Codes (online version) haascnc.com
Ministry of Health, Labour and Welfare (MHLW), Human Resources Development Bureau, Office of the Councillor for Skills Evaluation — Human resource development manual using the practical exam tasks of the Grade 3 Skilled Worker Test: CNC lathe work (March 2018) waza.mhlw.go.jp