[super95awd]

Alright guys, I'm baffled. My machine is a 2011 VF-2 with probes.

Yesterday I was running a program that I always run, and I noticed a bit of an anomaly in appearance. My ballnose that was running surfacing toolpaths was cutting too deep it seemed, which is odd because I just measured all the tools before this part. So I stopped the program and started remeasuring all the tools. Most all of them measured shorter than when I measured them before the program, some as much as .015" shorter. The ballnose was the closest to its original measurement which is why it was cutting too deep. I packed it in for the night, came down tonight, and first thing, warmed up the machine and measured all the tools again. All of them measured shorter than when I left last night, some were only off .0003", while some were off .0125". At this point, I can't make sense of it.

The Haas service tech was here yesterday before I started running to check out an odd spindle noise (sort of like whipping wind or a plugged up shop vac) that I was getting at 7500rpm and above (10k spindle). He couldn't nail down any explanation, but he did find that the spindle didn't seem to be getting enough lube. This spindle has 400 hours on it and has never been crashed. It just doesn't sound right to me.

Any insight guys?

[txcncman]

First, verify that the spindle itself is not moving in Z from tool change to tool change and from operation to operation. Should be easy enough to check by removing tool and referencing to a point off the table or vise. Then next, verify that the tools themselves are not moving in the tool holders. I bet you will find your ball mill being too long is because it moved.

[Matt@RFR]

When is the last time you calibrated your tool setter and spindle probe?

[super95awd]

The spindle probe and tool setter were reclibrated quite recently.

The weird thing is that the ball mill wasn't long and it hadn't moved, just suddenly all the rest of the tools (measured 10 min before) were too short. Most of those tools hadn't even touched aluminum yet. Wild. I checked repeatability of the tool setter by doing a "best out of 5" type approach and switching back and forth from the tool to make sure it was seating in the spindle reliably. This revealed no more than a .0001" change. I reset all the tools and ran a number of good parts tonight. I'm going to check it again tomorrow and see if anything has moved. I'll let you guys know if anything else weird has happened.

[txcncman]

What about a chip stuck to the top of the probe by dried up coolant?

[haastec]

First, verify that the spindle itself is not moving in Z from tool change to tool change and from operation to operation. Should be easy enough to check by removing tool and referencing to a point off the table or vise. Then next, verify that the tools themselves are not moving in the tool holders. I bet you will find your ball mill being too long is because it moved.

You need to do these steps to figure things out. You need to determine where the error is occuring; is the problem with the machine or is it with the probe system. You cannot move forward until you determine this.

Report back your findings.

[haastec]

When is the last time you calibrated your tool setter and spindle probe?

Anytime there is a question about accuracy, I always recommend recalibrating the probe. That way you can eliminate that as a possible cause.

[behindpropeller]

This thread seems to be drifting.

He is talking about TLO after being calibrated. Running the calibration back to back should have very small errors in repeatability.

To be honest, I have the same problem with my Marposs toolsetter. The probe is dead on!

Tim

[haastec]

This thread seems to be drifting.

He is talking about TLO after being calibrated. Running the calibration back to back should have very small errors in repeatability.

To be honest, I have the same problem with my Marposs toolsetter. The probe is dead on!

Tim

Actually I see all of the posts as quite relevant.

Regarding the calibration, he said that the probe and tool setter were calibrated "quite recently"; I have no idea how long ago that was and who did it. For me, I want to make sure it was done and done correctly.


You are correct that running back to back calibration cycles should have very small errors in repeatability and is unnecessary, but for troubleshooting, I feel that a new calibration cycle is necessary to establish a new baseline. Also, by calibration, I mean indicating everything and then running the calibration cycles.

The original poster needs to do some more homework. The problem needs to be isolated better and some variables (sources of problems) removed.

A few tenths difference in TLO after setting with the tool setter is fine in my book, but anything over .001" variance needs to be addressed. The OP is seeing up to .015".

[Machineit]

Actually I see all of the posts as quite relevant.

Regarding the calibration, he said that the probe and tool setter were calibrated "quite recently"; I have no idea how long ago that was and who did it. For me, I want to make sure it was done and done correctly.


You are correct that running back to back calibration cycles should have very small errors in repeatability and is unnecessary, but for troubleshooting, I feel that a new calibration cycle is necessary to establish a new baseline. Also, by calibration, I mean indicating everything and then running the calibration cycles.

The original poster needs to do some more homework. The problem needs to be isolated better and some variables (sources of problems) removed.

A few tenths difference in TLO after setting with the tool setter is fine in my book, but anything over .001" variance needs to be addressed. The OP is seeing up to .015".

+1. The recalibration needs to be done after a problem surfaces, not before. It must be verified.

Mike

[super95awd]

I didn't make it back to machine today, was having Valentine's day festivities.

Tomorrow I will go ahead and re-level the tool setter pad and recalibrate, and check runout on the spindle probe and recalibrate. I'll report back with my findings after I do that. I will also try to eliminate the machine as a possibility.

Sorry for the possible vague-ness, but that is honestly the best that I could describe it. It doesn't seem, to me anyways, the the problem has to do with tool setter repeatability and that's why I am particularly confused. It seems as if all my tool length offsets just went out the window randomly. Like I said, last night it did make good parts and the tool offsets did not vary by more than a couple tenths in between parts. To eliminate any tool setter errors due to chips or anything, I religiously blow off the pad and tool to be measured, so that could not be a source of the error.

I will update you guys as soon as I can eliminate some problem areas.

[txcncman]

Be extremely careful blowing high pressure air around the tool touch probe. Much better to wipe with clean soft cloth.

[haastec]

I didn't make it back to machine today, was having Valentine's day festivities.

Tomorrow I will go ahead and re-level the tool setter pad and recalibrate, and check runout on the spindle probe and recalibrate. I'll report back with my findings after I do that. I will also try to eliminate the machine as a possibility.

Sorry for the possible vague-ness, but that is honestly the best that I could describe it. It doesn't seem, to me anyways, the the problem has to do with tool setter repeatability and that's why I am particularly confused. It seems as if all my tool length offsets just went out the window randomly. Like I said, last night it did make good parts and the tool offsets did not vary by more than a couple tenths in between parts. To eliminate any tool setter errors due to chips or anything, I religiously blow off the pad and tool to be measured, so that could not be a source of the error.

I will update you guys as soon as I can eliminate some problem areas.

Be sure to do 2 separate testing methods. One using the tool setter then retest again, but manually set the tools this time.

[jason roy]

A chip or dirt in the spindle when the tools were originally measured?

[JimBoyce]

How about that spindle noise, can the thrust bearing nut be loose. Check spindle end play perhaps.

[Delw]

you said ball nose and surfacing. if your plunge or down feed heavy?
is your tools tight in your tool holder? if your using screw in style holders it might be time to replace the lock screw.

I usually replace the screws about every 3-6 months depending on what I am cutting and how big an endmill I am using. I retighten them about every 10-30days and if there new screws always with in 2 days to reseat.

Delw