[Python_Draper]

Hey guys,

Based on what I've been reading, there seems to be mixed reviews on what G96 Sxxx does. Is the S value an RPM or a SFM/MPM? I understand what the relationship between these values are however am just looking for clarification as to whether in the situation I have the following situation.

Diameter 6.0 inch
SFM 120

Would I write..

G96 S120

Or

G96 S76

Thanks guys! First post!

[z369]

Hey guys,

Based on what I've been reading, there seems to be mixed reviews on what G96 Sxxx does. Is the S value an RPM or a SFM/MPM? I understand what the relationship between these values are however am just looking for clarification as to whether in the situation I have the following situation.

Diameter 6.0 inch
SFM 120

Would I write..

G96 S120

Or

G96 S76

Thanks guys! First post!

G96-Constant Surface Speed

There shouldn't be any "mixed review" machining generally uses G96, or G97 which you would use for a tool (usually a drill, threader or a tap) in which case you're using the actual cutter for your calculations.
If your tool recommendation starts at 120SFM, your G96 should be 120.
All you need to do to calculate Surfsce m/min is convert a meter to a foot.
1meter=3.28 feet, therefore 120 x 3.28=393 feet per minute.

Feet per minute and meters per minute are two completely different things.

[rcs60]

it would be written as
G96S120
The control would then figure from the dia. position of the tool how many rpm's that it should be turning IE at 120 sfm and 6.00 inches the spindle rpm would be 76
an other thing that you should also do is to add a rpm limiter g50 sxxxx to keep the spindle from running to fast for you chuck or balance issues other wise at x0 the rpm's will be what ever the machine is capable of.
do this before g96