Engraving on rotary "A" axis, chatter problems

[jim1960]

I am a  HAAS VF2, with rotary

Stock is 1" alum using a 1/8 ball end mill

I have feed set at .2 and have tried RPM form 2500 to 4500

Straight lines on axis are great but when rotating I get chatter.

 

Thanks

 

 

[Micromoldmaker]

What is the depth you are cutting?

[mkd]

sounds like a feed rate change during rotation.

using g93?

 

post up an excerpt of the program.

[htm01]

rotation trying to go too fast is my guess

[Micromoldmaker]

 

rotation trying to go too fast is my guess

It's been many moons for me, but don't indexers have a feed ratio that you have to apply to your milling feed when you mill rotations?

[guitar]

Do you have a Hardinge rotary table on your Hass?

[Machineguy]

One thing, change your RPM to 10,000 for Alum. with a 1/8 cutter.

[htm01]

on our has rotary can't go over F10. IPM or it starts jumping

[CJep]

Have you tried running in deg/min output for the rotary positioning?

How many decimals are you formatting to in the rotary code?

 

G93 is inverse time that will work as well, it may end up running a bit faster though.

[taperlength]

Could be it just needs shorter moves.  

[civiceg]

It should be done with G93, there is no other way to get accurate feed rates on a 4th axis cut on a Haas VMC. Its not like its a FANUC and you need to have the option turned on.....you have it. 

[jim1960]

Here is some of the code.

How do I put in a G93 within Mastercam?   Is there anything else that has to be added when using G93?

 

Thanks

 

N100 G20
N110 G0 G17 G40 G49 G80 G90
N120 T17 M6
N130 G0 G90 G54 X.4 Y0. A18.435 S2500 M3
N140 G43 H17 Z.7906
N150 M8
N160 Z.447 A34.009
N170 G19 G1 Z.4444 A28.935 F.2
N180 Z.4422 A23.829
N190 Z.4404 A18.698
N200 Z.439 A13.546
N210 Z.4381 A8.378
N220 Z.4376 A3.201
N230 Z.4375 A-1.979
N240 Z.4379 A-7.157
N250 Z.4388 A-12.328
N260 Z.44 A-17.485
N270 X.399 Z.4406 A-19.438
N280 X.3931 Z.4416 A-22.396
N290 X.3843 Z.4427 A-25.059
N300 X.3716 Z.4437 A-27.42
N310 X.3559 Z.4448 A-29.814
N320 X.3382 Z.4457 A-31.547
N330 X.3186 Z.4464 A-32.949
N340 X.2971 Z.4468 A-33.655
N350 X.2755 Z.447 A-34.009
N360 X.2539 Z.4468 A-33.655
N370 X.2333 Z.4464 A-32.949
N380 X.2127 Z.4457 A-31.547
N390 X.1951 Z.4448 A-29.814
N400 X.1804 Z.4437 A-27.42
N410 X.1676 Z.4427 A-25.059
N420 X.1578 Z.4416 A-22.396
N430 X.1529 Z.4406 A-19.438
N440 X.15 Z.4395 A-15.545

[civiceg]

It will depend upon your post. If you are using a MPmaster post, its very easy. 

[bigjohn]

Have you tried running in deg/min output for the rotary positioning?

How many decimals are you formatting to in the rotary code?

 

G93 is inverse time that will work as well, it may end up running a bit faster though.

deg/min output for the rotary positioning