speed/ feed relationship in program

[CNC-Hammer]

Hi Guys,

I came across an IGF program on a Spaceturn LB4000EX which was milling using an 80mm face mill which showed the Vc at 120m/min but the rev's was at approx. 1400RPM. By my reckoning the rev's should be closer to 470.
Everywhere else in the program appeared to be correct but I could not find anything to link this in the ISO program bar the following variable:
VLMON[3]=113 which, I believe is a load monitor.

Can anyone suggest what would be the cause of the discrepancy?

[budgieW]

So what is the question?

VLMON[3] is the load monitor using page 3

[Superman]

What material did they select for the calculations ?

I agree with 470 RPM with Ø80 cutter = 120 Vc
but the 1400 RPM for the same cutter = 352 Vc which may be a setting closer to Alum.

[Algirdas]

what would be the cause of the discrepancy?
cutting speed is related to diameter of rotating tool and revolution speed. See Your tool description. Is part program created by IGF? You need to describe tool properly.

[CNC-Hammer]

So what is the question?

I am wondering why the RPM and the Vc for a given tool do not tally for a specific op ie roughing, although directly following the roughing op, the RPM and Vc correlate for the same tool for a finishing op.

If that makes sense. Is should have explained it better before, but I think I'll have a look at the IGF data.

[montyLalor]

I came across an IGF program...

In coming across what I can only presume was a MIN nc program coupled with an native IGF file, then have you perhaps considered that the creator of both edited the MIN file after 'posting' from IGF, so that said discrepancy is present?

Luke

[CNC-Hammer]

In coming across what I can only presume was a MIN nc program coupled with an native IGF file, then have you perhaps considered that the creator of both edited the MIN file after 'posting' from IGF, so that said discrepancy is present?

Luke

Nope, all edits are done in IGF

[CNC-Hammer]

what would be the cause of the discrepancy?
cutting speed is related to diameter of rotating tool and revolution speed. See Your tool description. Is part program created by IGF? You need to describe tool properly.

Spot on!

It appears the tool description was incorrect. It was created thus to allow the tool to perform a particular move.