Good morning PM.
I have a 2019 VF2SS. About two months ago I noticed when the table would rapid feed from -Y to +Y and you would hit feed hold to check distance to go and what not, the entire machine would make a dull, but very noticeable thud. Enough to feel it in the floor, hear it, and if my eyes are correct see the table shake but not the base casting.
When fine surfacing humps or hills the cutter would leave very small gouges below the rest of the programmed toolpath that would make tumbling take many extra hours. I am also getting a worse finish on vertical walls when using Y motion, vs X. The surface finish is worse when using both X / Y together. 3D surfacing with XYZ will often result in a really strange faceting. The last thing I was running was a toolpath with a 1/4 ballmill, in 62 HRC stainless, starting in +Y +X -Z and traveling in a fixed linear 30 deg move 2" to -Y -X +Z which left facets that where parallel to x axis. At first I thought the lines it left where from the chip load being match .002" FPT to .002" step over, but when the part was tumbled those parallel marks where deeper then the 30 deg programmed cuts.
When running a toolpath at 30ipm with a lot of tiny linear moves, moving from +Y to -Y the machine makes a very distinct whirling sound. This started happening right around the time the thudding started happening.
History: Purchased new in Sep 2019, the mill has been sorta mostly okay as far as finishing stuff goes. Passable with a lot of massaging. I'm milling high hardness stainless and titanium. It's been crashed, probably 4 times worth mentioning. Twice into the HRT210 in Z rapid, once into a flat table fixture in Z rapid, and once with a really long tool into the side of a part that was on the 4th axis traveling in +Y. That last one I don't think was that bad because the tool holder was 6" long, and still had good TIR but its hard to say.
Machine started with everyone's favorite purple grease. Which then ran tan. Which then clogged. Switched to the new oil. Still had residual pressure alarms. Ended up spending way to long clearing every single axis lube metering restriction. When I got to it the linear rails were dry, but the ball screws had a film of oil, no visible dings, rust, anything out of the ordinary. Got it lubing again properly and it hasn't thrown any alarms since. That was 3 weeks ago.
Trying to figure it out: If I do a test and max feed(833ipm) moving the table back in forth in Y and feed hold it, the thud is very reliable to reproduce. Interestingly it will only thud if the machine is in G187 P2, or P3. These are smoothing modes. Thud is less in P2 vs P3. In G187 P1 the table accelerates and stops very quick, but it will not cause a thud. Also running the same test in X it will thud, but it is a bit harder to reliably to make the sound. When the sound it made I am 90% confident the table is shaking, and not the base, as far as my eyes can see. When doing the test in Y, the Z axis load meter will jump from 46% to 54%, and stay there until an axis is jogged.
Idle axis loads are 0-1% X, 3-4% Y, 46% Z.
What do you guys think? I am leaning towards something is loose involving y axis travel, cracked bolt, misalignment of something, and I've also heard about maybe its the thrust bearing. Though I'm not sure how to reliable check for that. If the machine didn't thud I would of honestly let it ride, but it's loud enough to be concerning. Not sure if the axial ball screw movement is supposed to have some, or zero play.
Thanks for any help
- Jon
I have a 2019 VF2SS. About two months ago I noticed when the table would rapid feed from -Y to +Y and you would hit feed hold to check distance to go and what not, the entire machine would make a dull, but very noticeable thud. Enough to feel it in the floor, hear it, and if my eyes are correct see the table shake but not the base casting.
When fine surfacing humps or hills the cutter would leave very small gouges below the rest of the programmed toolpath that would make tumbling take many extra hours. I am also getting a worse finish on vertical walls when using Y motion, vs X. The surface finish is worse when using both X / Y together. 3D surfacing with XYZ will often result in a really strange faceting. The last thing I was running was a toolpath with a 1/4 ballmill, in 62 HRC stainless, starting in +Y +X -Z and traveling in a fixed linear 30 deg move 2" to -Y -X +Z which left facets that where parallel to x axis. At first I thought the lines it left where from the chip load being match .002" FPT to .002" step over, but when the part was tumbled those parallel marks where deeper then the 30 deg programmed cuts.
When running a toolpath at 30ipm with a lot of tiny linear moves, moving from +Y to -Y the machine makes a very distinct whirling sound. This started happening right around the time the thudding started happening.
History: Purchased new in Sep 2019, the mill has been sorta mostly okay as far as finishing stuff goes. Passable with a lot of massaging. I'm milling high hardness stainless and titanium. It's been crashed, probably 4 times worth mentioning. Twice into the HRT210 in Z rapid, once into a flat table fixture in Z rapid, and once with a really long tool into the side of a part that was on the 4th axis traveling in +Y. That last one I don't think was that bad because the tool holder was 6" long, and still had good TIR but its hard to say.
Machine started with everyone's favorite purple grease. Which then ran tan. Which then clogged. Switched to the new oil. Still had residual pressure alarms. Ended up spending way to long clearing every single axis lube metering restriction. When I got to it the linear rails were dry, but the ball screws had a film of oil, no visible dings, rust, anything out of the ordinary. Got it lubing again properly and it hasn't thrown any alarms since. That was 3 weeks ago.
Trying to figure it out: If I do a test and max feed(833ipm) moving the table back in forth in Y and feed hold it, the thud is very reliable to reproduce. Interestingly it will only thud if the machine is in G187 P2, or P3. These are smoothing modes. Thud is less in P2 vs P3. In G187 P1 the table accelerates and stops very quick, but it will not cause a thud. Also running the same test in X it will thud, but it is a bit harder to reliably to make the sound. When the sound it made I am 90% confident the table is shaking, and not the base, as far as my eyes can see. When doing the test in Y, the Z axis load meter will jump from 46% to 54%, and stay there until an axis is jogged.
Idle axis loads are 0-1% X, 3-4% Y, 46% Z.
- Leveled the machine beginning of the week. No change in any of the above problems. No soft feet. 10" TIR on table reads .0000" front, - .0003" left, - .0002" rear, - .0002" right. When having the level parallel in Y and going from front to back, there is a .0006" bow that is impossible to correct with the feet. It's also always been like that since I leveled it the last time, so I don't know if that's relevant.
- X axis backlash less then .0002" both on the ball screw and the table. X axis ball screw axial movement is less then .0001" and returns back to position. When read from the end of the screw towards the support bearing.
- Y axis backlash less then .0002" both on the ball screw and the table. Y axis ballscrew axial movement is 0.0001" - 0.0002" and returns to position.
- Z axis backlash less then .0002" but when read at the spindle nose its .0003" vs the ballscrew. Axial movement is .0002" and returns to position. Not sure if the different readings nose vs ballscrew is because of gravity or how I measured it. Pushing the spindle head it moves as expected, but returns to position when let go of.
- Indicator base attached to X axis casting, prying up at 4 corners, no linear truck appears to be loose. Every reading was .0002" but returned to normal.
- Indicator base attached to Y base casting, prying up at 4 corners, no linear truck appears to be loose. Every reading was .0002" but returned to normal.
What do you guys think? I am leaning towards something is loose involving y axis travel, cracked bolt, misalignment of something, and I've also heard about maybe its the thrust bearing. Though I'm not sure how to reliable check for that. If the machine didn't thud I would of honestly let it ride, but it's loud enough to be concerning. Not sure if the axial ball screw movement is supposed to have some, or zero play.
Thanks for any help
- Jon
