Lathe Constant Surface Speed

[Droogie]

Could someone explain to me just what is going on with the spindle RPM when you check the CSS box in the lathe tool parameters page. More specifically, is Mastercam working from the Maximum Spindle Speed you enter or from the Spindle Speed you can also enter. Or is it a combination of the two? We know the spindle speeds up as you move towards the centerline of part but just how is the speed determined?

[gcode]

quote:

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how is the speed determined?

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Surface feet x 3.82/diameter of the cut is a good

aproximation

 

the default Mastercam posts output an RPM that

corresponds to the first X approach postion,

then outpouts the G50 spindle rpm clamp value

then the SSF value you entered on the operation page

[Guest]

It is determined the the Surface Feet per minute

 

G50 S2500 will cap your RPM at 2500

 

G96 S400

 

will force the spindle to turn at a speed equivalent to the surface footage set on the G96 line while stopping at 2500 RPM

 

SFM 400 x 3.82/by a 3.00 diameter will give a you a spindle speed of 509

 

the same SFM at 2.00 diamter will be 764 RPms

 

It is all dictated by SFM

 

Does that help?

[LiquidFooosh]

how do you know what a good CSS is for certain materials like hardened steels?  also when facing a part what is a good CSS to set?

[AHarrison1]

10 minutes ago, LiquidFooosh said:

how do you know what a good CSS is for certain materials like hardened steels?  also when facing a part what is a good CSS to set?

This will depend on the tool (insert) manufacturer's recommendations for that particular insert, coating, machine rigidity, etc, etc.

I generally just worry about the recommendations

[neurosis]

1

I just wanted to post on a 16 year old post.  I don't get to do that very often.   

[byte]

15 minutes ago, neurosis said:

1

I just wanted to post on a 16 year old post.  I don't get to do that very often.   

pretty sure someone resurrects a 15+ y post about once a week, 

i feel like there room for a joke here but im drawing a blank

[crazy^millman]

2 hours ago, LiquidFooosh said:

how do you know what a good CSS is for certain materials like hardened steels?  also when facing a part what is a good CSS to set?

You educate yourself by doing exactly what was mentioned here

2 hours ago, AHarrison1 said:

This will depend on the tool (insert) manufacturer's recommendations for that particular insert, coating, machine rigidity, etc, etc.

I generally just worry about the recommendations

 

[Jobnt]

2 hours ago, byte said:

i feel like there room for a joke here but im drawing a blank

Just throw "roofie" in there and the jokes will write themselves.