[CryoTurbo]

Hi Guys,

Newbie here, have a '97 Fadal VMC-2216 with a TR-65 Head doing 5-axis simultaneous machining (Impellers). During the roughing cut, the back side of the blades ends up with gouge-like marks along the blade length. The front side comes out beautiful. I'm using point climb milling (not flank) with carbide ball end mill. It's a repetitive pattern on every blade. Anyone have any ideas why this is occurring? Not sure if it's backlash on A axis problem, angular problem or if it's in the program. I've included a couple of jpegs, to show what's happening.

[holbieone]

it's hard to tell whats going on with out watching the motion of the cuts

are you climb milling on both sides of the splitter ?

try finishing the splitter and see what the surface looks like

[txcncman]

Are you using MasterCam to program?

[carbidecraters]

You should check your servo tuning as well as backlash before doing 5 axis work. Youll want at least a .0001 indicator if not a .00005 indicator to set backlash. IIRC XYZ will need to be tuned to 302 and A and B to (hmm cant find that one)

Quote from the manual for DC drives

1) Enter the following program:
a. X-4. Y-4. Z-4. G1 F150. M49,M91.
b. X4.Y4.Z4.
c. M99P1
2) Press Auto, to start the program running.
3) At the amplifier to be adjusted, use a small screwdriver and turn the SIG2
potentiometer until the monitor’s display of the appropriate axis reads the
following: 595 - inch ballscrew / 302 - metric ballscrew.
4) Press the SLIDE HOLD button on the keypad and adjust the balance of the
amplifier to read between 0 - 1.
5) Press the START button on the keypad and the program will start again.
Verify that the following error is still 595 or 302.
6) Press the SLIDE HOLD key to stop the machine. Press the MANUAL key and
then type SETCS and HO, to send the machine home. Adjustment of the
amplifier is complete. Repeat the procedure for all axes

[CryoTurbo]

Hi guys,

First many thanks for the quick replies!
I am climb milling both sides, holbieone, I'll see if I can get a video upload so you can see the motion. I'm not a "real" machinist, just playing around a bunch and learning as I go. I'm not using Mastercam, txcncman, I'm using specialized turbomachinery machining software as I work for a turbomachinery company. I do use Surfcam for 3-axis parts and cnc lathe work. Many thanks carbidecraters, I'll give your procedure a try as soon as I can get a chance. I think it's been a long time since any calibration been done on this Fadal.

[pilot001]

HI !
:tired:

Am i right that to use this small program (correctly) the CNC has to be set to INCH unit ?

We have a 4020ht with Metric srews and we use it in METRIC as well (what else)

So to set it up correctly i have to use SETP and change the "system" to INCH. Then i can use this Prog. The travel is not really important just the F150 (IPM) and of course M91 M49 (to eliminate the feed rate adjuster pot.)

[holbieone]

Hi guys,

First many thanks for the quick replies!
I am climb milling both sides, holbieone, I'll see if I can get a video upload so you can see the motion. I'm not a "real" machinist, just playing around a bunch and learning as I go. I'm not using Mastercam, txcncman, I'm using specialized turbomachinery machining software as I work for a turbomachinery company. I do use Surfcam for 3-axis parts and cnc lathe work. Many thanks carbidecraters, I'll give your procedure a try as soon as I can get a chance. I think it's been a long time since any calibration been done on this Fadal.

so your plunging the bottom of the tool on that side , try a liter depth of cut with a little more forward lean


"turbomachinery machining software" ug , nx or nuform

[Neal]

Backlash???? Loose Straps????

[CryoTurbo]

Ok, I haven't as yet implemented carbidecraters procedure (will do in near future) but found out that by milling each side individually helped tremendously. The front side was climb milled and the back side was conventional milled, worked like a charm. I'm still thinking that this machine has an A axis backlash issue but won't be able to check for this until a later time.

Thanks for the all help.