Chatter in X+ only, X- sounds fine.

Found the reset button on the previous issue and the Fadal is working again. just not perfectly.

New spindle, new idler pulley assy, new spindle pulley.
draw bar pressure is 1550psi.
2 hour run in, multiple times, max temp at nose 74F.
Sounds and runs great.

The part is flimsy, the endmill is extended etc, however, the cut climb milling from X1.25 to X0 sounds fine.
The cut on the opposite side of the part climb milling from X0 to X1.25 squeals like Ned Beatty in a life jacket.

I even reduced the radial depth of cut from .040 to .030 on the X+ movement but it still squeals.

To me, that sounds like a gib adjustment issue, probably needs to be snugged up just a bit as it is shifting in position. Does this make sense or am I looking in the wrong direction?

What if you are just running with no part in there, just "cutting air" as they say?

Where is the noise coming from?

Did you try different feedrates?

Is the rest of the set-up decent?

My money's on one of the X axis thrust bearings being bad. When you move one way the screw loads against one bearing, and when you move the other it loads against the opposite.

Worked at a place that had an accuslide (fagor on an old hardinge). The Z axis was silky smooth in one direction,
but was almost like a ratchet in the other direction. One thing to look at..

The other thing I would look at isn't the X ways, but the Z.. Are the gibs loose in the X direction, so the head can turn
like a clock, and I've seen it where in the Y, where if the tool pressure was pushing in towards the column it was
fine, but when the tool pressure pulled away from the column things got ugly. Though it sounds like you
are having the opposite problem.. And little tool pressure...

I'd also go after thrust bearings first. Then the X axis gibs.

litlerob1 said:

What if you are just running with no part in there, just "cutting air" as they say?

Where is the noise coming from?

Did you try different feedrates?

Is the rest of the set-up decent?

Click to expand...

It is a squeal from the cut, not the screw. It really sounds the same going either way.
On the thrust bearings, if I just add an extra shim between the two bearings that should tighten it up, right?