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  1. #41
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    I checked the alignment of the TS27R and it's perfect
    I also made sure the little nut was tightened.
    And I've put a dial indicator against the TS27R stylus and measured length and diameter.
    When I push the taster by hand it returns perfectly to its starting position. There's no variation in readings (I had 0,06mm in diameter).
    So the actual stylus is good.

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    If the results were repeating but incorrect I say the deflection cycle hasn't been run or is incorrect. Also the machine needs to know the machine coordinates of the centre of the anvil. This been incorrect can also give rogue readings.

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    Quote Originally Posted by tcncj View Post
    I checked the alignment of the TS27R and it's perfect
    I also made sure the little nut was tightened.
    And I've put a dial indicator against the TS27R stylus and measured length and diameter.
    When I push the taster by hand it returns perfectly to its starting position. There's no variation in readings (I had 0,06mm in diameter).
    So the actual stylus is good.
    And they are still investigating ...

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    usually a probe will repeat within .0002" assuming it doesnt have sticky residue on probe tip or there is no dirt on the part measured. or there is no sticky residue in the probe. i have seen probes intermittently get stuck in the contact position. usually call maintenance to change probe cause cleaner mixed in coolant causes rubber orings to swell bigger and get sticky
    .
    i have seen a probe occasionally go beep and not backup and start bending probe tip often to the point of tip failure, if not broken but tip bending i have taken picture showing probe tip bending, cause maint guy often doesnt believe it happened without pictures. obviously a electronics problem. that often on a machine restart and it stops doing that for awhile. i have seen probe get tripped or beep early cause it sensed vibration from machine and then do odd stuff like probe at the wrong spot. and when probing repeated it worked ok the 2nd time. machine vibration can be as simple as a sliding vertical way cover all of a sudden drop a few inches and cause a thump or vibration
    .
    some probes have a hysterious error correction based on probe feed speed. if feed not at 100% it can cause errors

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    Quote Originally Posted by DMF_TomB View Post
    usually a probe will repeat within .0002" assuming it doesnt have sticky residue on probe tip or there is no dirt on the part measured. or there is no sticky residue in the probe. i have seen probes intermittently get stuck in the contact position. usually call maintenance to change probe cause cleaner mixed in coolant causes rubber orings to swell bigger and get sticky
    .
    i have seen a probe occasionally go beep and not backup and start bending probe tip often to the point of tip failure, if not broken but tip bending i have taken picture showing probe tip bending, cause maint guy often doesnt believe it happened without pictures. obviously a electronics problem. that often on a machine restart and it stops doing that for awhile. i have seen probe get tripped or beep early cause it sensed vibration from machine and then do odd stuff like probe at the wrong spot. and when probing repeated it worked ok the 2nd time. machine vibration can be as simple as a sliding vertical way cover all of a sudden drop a few inches and cause a thump or vibration
    .
    some probes have a hysterious error correction based on probe feed speed. if feed not at 100% it can cause errors
    All above is true, but the case we are dealing with here has nothing to do with that. Here we have a new machine, a new TS27R, not retrofitted by occasional electrician but fully installed by machine tool builder team in his factory. Additional probing instrument (OMP60) is performing as expected. The case is investigated for several days already by combined Renishaw/Hurco team. I hope that as the result of such severe brain storm they shortly will come with some productive ideas.

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    It always turns out to be something stupid.... Like the whole unit is moving because the screws holding it down are .020 too long and not tightening even though the wrench is tight when you turn them.....

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    +1 on the comments on set screws and alignment stuff. There are some very specific setup instructions for the OMP. Part of it is getting the stylus level- ie sweeping across it with a tenths indicator. There are two setscrews for both the x and y rotation of the stylus - they have to be tensioned against each other. You essentially have to keep tightening the opposing screw as you sweep so they both meet Renishaw’s required tension. If only one set screw is tight the omp could be vibrating and causing error.

    Also- have you calibrated the stylus with a reference tool? I have the maritool one, it’s a good investment. You didn’t mention if you used one of these but it’s much easier to go through the calibration process in the hurco control with one. Hurco has a specific setup sequence and I didn’t see any mention that all of that was done in your messages. You have to first use the part probe or indicator to find the center of the stylus. That gets stored in the tool probe screen. Then you have to use the reference tool to touch each side of the tool probe stylus(+x, -x, +y, -y). This creates a small offset in a table that accounts for any error in the center point. Mine are a few tenths each, of you haven’t done this it could be where your error is coming from.

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    What is the status now ? Did they solve the problem ?

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    @ the latest replies.
    OMP works, and repeats perfectly.
    TS27R doesn't.
    It's a brand new machine.
    It's not dirty
    The service guys have setup the Renishaw.
    Even if it was not aligned it would give repeatable measurements.

    Quote Originally Posted by PROBE View Post
    What is the status now ? Did they solve the problem ?
    No updates yet.

    I didn't get any news from the machine dealer (who sold me the machine).
    But the local Renishaw center (in the netherlands) has contacted my dealer directly, to investigate the problem. But they (renishaw) don't know the problem. They agree with me something is wrong and it's not a thermal growth issue because the OMP measures perfectly.
    I've send a mail to my Hurco dealer about the steps I have taken to solve this issue and I've send them my measuring reports. But they still want to let me believe it's machine growth. I'm 100% sure they just lack experience and have no idea what they are doing. And say "even a slight breeze of wind can change the actual readings". They don't seem to care about my arguments and facts that it's not a axis issue or machine growth. They can't explain anything, and don't seem to understand. It's a shame Hurco has chosen this company to resell their machines. Because it's my first and last Hurco, unless Hurco Germany can supply me a machine directly. Because I need a new lathe soon.
    They would contact me this week to make a plan on how to solve this. Of course I didn't heard anything from them.

    - A tool length probing which increases by 2-4 micron each time you probe is not machine growth! When I probe 100 times the different is 0,1mm. When I probe 150 times it's 0,15mm difference.
    - Diameter probing has a variation of 0,06mm. Sometimes the value is big and then it's smaller. So if it's machine growth it's increasing or decreasing. And not changing all the time.
    - Besides there is a difference in X and Y axis diameter probing of 0,1mm.
    - All tested with a cold and warm machine
    - OMP60 is perfect and repeats (cold and warm machine, 25 times tested) within 2 micron.

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    At this point, they could have sent you a new probe installed it and checked it to at least rule out a faulty unit... (and point to a software issue maybe?)

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    Quote Originally Posted by tcncj View Post
    1) exactly! that's what I said to the mechanic. The OMP measures perfectly! tested/calibrated on a ring gauge. So it's not a machine issue.
    Besides I did measure backlash on all axis before the mechanic came in. To make sure it was not the machine. And it indeed had backlash...
    He then tested it with ball thing and a program to let the machine interpolate. He got some readings on his notebook and adjusted the backlash in the software.

    2) Yep 0,001mm is in best case scenario. But the variations I get are way too big. It was +/- )0,02mm at the end of the day. Sometimes a negative value and sometimes a positive value. Measured with a gauge pin.
    3) I will try that next week


    He did run it at 25mm/min.
    And then at 4mm/min.
    Yes it still had big variations between measurements
    I haven't dug super deep on this thread with meticulous care … But

    Questions for you …

    1. Does your machine have scales ?

    2. Can you post the ball bar plots ?


    I'm guessing your machine does not have scales.

    I'm guessing something is loose on your machine, like ball nut (on ball screws), or the way a thrust washer / bearing block is seated etc. etc.

    It's also possible that your pitch error compensation plots/tables are 'Messed up"


    But overall sounds like something is mechanically loose on the machine.


    Remember a VMC is not a CMM ! So if the machanics of the machine are messed up and you have no scales then the machine won't know where it is as compared to a actual metrology based reality of some sort.


    @tcncj I really hope you sort this out, sounds like you are being given "The Runaround" from different groups in the chain BUT the Ballbar tests and plots (if carried out properly) should reveal a hell of lot about the machine (independently from the probing / tool setter stuff, which seems sound (most probably)).

    Also not to Dump on Hurco 'cuz they do some good things, but lathes/ turning centers are not their strong suit. You might also look elsewhere for a turning center perhaps ?

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    Quote Originally Posted by cameraman View Post
    ....

    Questions for you …

    1. Does your machine have scales ?

    2. Can you post the ball bar plots ?
    ,,,

    Remember a VMC is not a CMM !
    From the op "OMP works, and repeats perfectly."
    A clue in there to machine/ball bar and servos. Did you miss that info or just asleep at the wheel?
    Bob

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    Quote Originally Posted by CarbideBob View Post
    From the op "OMP works, and repeats perfectly."
    A clue in there to machine/ball bar and servos. Did you miss that info or just asleep at the wheel?
    Bob
    machine is tested with a renishaw ball bar. It had 2-3 micron backlash. It was adjusted and now it's perfect. I checked this by myself to be 100% sure.
    It's not a axis/accuracy of the machine issue.

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    Quote Originally Posted by CarbideBob View Post
    From the op "OMP works, and repeats perfectly."
    A clue in there to machine/ball bar and servos. Did you miss that info or just asleep at the wheel?
    Bob
    Until you actually see the ball bar plots... Seeing is believing.

    Also I have seen ball bar tests being completely misinterpreted sometimes by a factor 10X and in rare cases a factor 100.

    The OMP / fancy switch can repeat superbly but that does not necessarily mean the machine travels long distances with high repeatability or high repeatability AND accuracy bi-directionally on the table at different intervals and at different positions on the table. Red flag for me was difference in speed. To "Indicate" that something is loose like others have said. I.e. a grossly disproportional effect of inertia at different speeds, (even taking into account what would normally happen at different speeds when everything is Ok) this disproportional effect being caused (perhaps) by something being loose. That also does not include the fact that the reported and commanded distances travelled match up either, even though repeatability in single spot measurements in isolated cases can be "Repeated" as such. That's where linear laser interferometry plots come in to determine the difference between commanded position and actual positions. Hence mapping out of ball screws and pitch error compensation (as ball screws even really GOOD ones are not as linear or accurate as we might like or suppose or believe (uncalibrated.)). But all the different patterns and diagnostics that can be determined by ball bar plots without linear laser interferometry plots never the less are quite impressive.


    I'll re-read and "Do" my due diligence. Thanks for that @CarbideBob

    As a betting man I'd say Renishaw is a far simpler and more reliable system than lets say a Hurco VM 10i (in terms of stuff that can actually go wrong)./ especially given the context of everything that OP has reported thus far.

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    Quote Originally Posted by tcncj View Post
    machine is tested with a renishaw ball bar. It had 2-3 micron backlash. It was adjusted and now it's perfect. I checked this by myself to be 100% sure.
    It's not a axis/accuracy of the machine issue.
    And circularity ?

    What shape is the actual plot ?

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    @tcncj what IS the temperature range daily in your shop from early morning to Maximum temperature during the day ... Just so we can really eliminate that. We can "Do" the math on that and what the Hurco control tries to implement as thermal compensation.

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    Quote Originally Posted by tcncj View Post
    Hi all,

    <Some edits> / <snips for clarity + Emphasis added >.

    I've got a question regarding Renishaw probing.

    We've bought a new Hurco VM10i since a month with the complete probing package (TS27R and OMP60)
    There we're allot of issues with installation and some issue are still present, due to a lack of knowledge from the service guy. Total disaster.
    I shall only tell the issues regarding probing, since that's where this topic is about. And otherwise the list will become too long.

    - renishaw workprobe stylus not adjusted so it had 0,03mm (0.118")runout.
    - toolprobe was not aligned on the table

    This was fixed today by a different service guy.
    But there are still issues.

    When checking diameter with a pin gauge in a collet the measurements are not consistent.
    When repeating the diameter probing the maximum difference between measurements was 0,08mm (0.315")
    That's huge!
    When adjusting the probing speed he could reduce the difference to within 0,02mm (0.08)

    And sometimes it gives an error about the max spread is exceeded.

    According to the Renishaw manual it should repeat to 0,001mm (micron) - <snip>


    <snip>
    <snip>

    Even my digital caliper is giving more consistent results.

    <snip>

    Then he said it was due to machine accuracy.
    That the toolsetter could repeat in a micron doesn't mean the machine can.

    True...but I'm sure the machine is accurate enough to repeat within 0,02mm / 0.078"
    And that wouldn't explain the variations between readings. And the slight decrease in variations when using a lower probe feed.


    So I'm checking if I'm going crazy or have a mechanic that doesn't know how it works?
    Why would you even probe diameter of the readings are way off and vary each time? Why would you want to update the tool wear like this?

    We didn't checked the tool length yet.
    But before the aligment of the TS27R there where also big variations in readings when the tool was rotating.
    I'll keep reading for proof that the machine is sound and nothing is loose. ?

    @tcncj have you cut any parts on this machine yet ?

    and what do you reckon is the runout of the spindle?

    I'm assuming the machine is NEW not second hand / used --- Is that correct ?

    Do you have a test bar for your spindle that you can indicate against for runout ?
    <<< I think someone suggested that already.

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    Quote Originally Posted by tcncj View Post
    <snip>

    <snip>

    - Besides there is a difference in X and Y axis diameter probing of 0,1mm.
    - All tested with a cold and warm machine
    - OMP60 is perfect and repeats (cold and warm machine, 25 times tested) within 2 micron.
    ? ¯\_(ツ)_/¯.*

    _________________________________________

    * I give up

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    Quote Originally Posted by tcncj View Post
    Hi all,

    <snip>

    <snip>

    I highly doubt this is correct. And the service guy is trying to let me think this is normal.

    He says non[e] of their customers use it the way how I want to use it (rotating a cutter and measuring the tool by length and diameter)
    And they only use it to check for length and broken tool detection. He called Hurco Germany and they said it was normal. Wtf? why spend 10.000 Euro on a probing package. Even my digital caliper is giving more consistent results. <snip>
    71afcf10f3a141f9b502526a86b86ee6-1-.jpg

    ^^^ So your service guy is telling you that no one does this ? Ever... ?

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    I still think it is a wiring issue with the fast probe input at TB4-31.

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