[daedalus0x1a4]

Hey,

This is the first Haas that I have been allowed to operate as I see fit. I am used to Okuma and Mori VM/HM's.

Today I am facing some A36 blocks with a 2" four-flute Sandvik Coromant Facemill. The inserts are TiN coated with a 0deg. lead angle and I am running the tool at 750 SFM and .012" LPT.

At an axial engagement of 1.6" and a radial engagement of .050" the spindle load is 90% but the motor in this machine tool is supposed to be 20HP so I am a little confused.

Is this the most I am going to get out of this machine or could it be damaged?

[txcncman]

90% is kind of low. I have seen these machines go to 120% or even 150% without actually tripping out on overload. How does it sound before entering the cut, during the cut, and leaving the cut? Does the RPM actually drop?

[daedalus0x1a4]

Well, it is supposed to be about a 5hp cut. Could it just be that the load sensor is sensitive?

It sounds like awesome for the most part. I need to get it off the extended holder but aside from that I don't see why it couldn't handle .015"-.020" LPT.

P.S. loses maybe 6 RPM

[txcncman]

The load meter might be out of calibration too.

[gizmo_454]

Well, it is supposed to be about a 5hp cut.

5HP cut? I am confused. Our Mini Mill can barely handle the 1" Mitsubishi APX 3000 we have at light feeds. That is 7.5HP. I couldn't imagine trying to run the depths and feeds you are talking with a 2" mill! Maybe you can explain how your arrived at your 5HP cut estimate.

Mike

[Rstewart]

Welcome to HAAS!

Is this a 7500 RPM gear driven mill or the 10K or 15K Direct inline spindle?

I've noticed a huge difference in performance.

[Rstewart]

Well from what I calc'd I got around 2HP cut......

This is ass-u-me-ing that your terms are Backwards When you stated the Axial and Radial engagements

Radial is W.O.C. and Axial is D.O.C

[daedalus0x1a4]

Haha, oops. I mix those up a lot.

This is a 7,500 RPM BT40 spindle that I believe is belt-driven, I haven't had a chance to take the covers off and take a peak.

But yeah, it's barely a cut!

gizmo, I just used a hokey horsepower calculator at iscar's website, all my books are in a box somewhere and I forget the equations.

[keebler303]

In short, your motor can't deliver much horsepower at slow speeds, that's why you want a gearbox when cutting a lot of ferrous materials.


In long, power is a function of both torque and speed. At low speeds, your power is limited by your torque. At 0 speed and full torque you will have 100% current and 0 mechanical power. The spindle is probably only capable of delivering 20HP in a small RPM range, generally down to half the nameplate speed (referred to as 2:1 constant hp). Below that, it goes into the constant torque regime, where power drops linearly with speed. Your load meter is a current meter so it will be maxed out in low speed high torque situations even though you are only getting a few HP out of it.

Matt

[Geof]

The 20HP is also a peak rating. Here are the torque/power curves for a 7500 rpm 20HP VF machine with no gearbox.

[daedalus0x1a4]

Thanks for explaining that and for the picture guys. Geof where'd you find that?

[Geof]

A friend sent it to me. I have several VF machines.