Results 1 to 11 of 11

Thread: OUCH: 0.0007% Error rate not acceptable

  1. #1
    Registered
    Join Date
    Jul 2005
    Location
    Canada
    Posts
    11,960
    Downloads
    0
    Uploads
    0

    OUCH: 0.0007% Error rate not acceptable

    On its 137,695th tool change my six years old VF0 decided it would not get a firm grip on the pull stud, jammed the holder against the side of the fixture and tried to feed down at 7500 rpm for a few seconds.
    Attached Thumbnails Attached Thumbnails OUCH: 0.0007% Error rate not acceptable-vf0tool2.jpg  


  2. #2
    Registered
    Join Date
    Dec 2005
    Location
    USA
    Posts
    3,319
    Downloads
    0
    Uploads
    0
    That is still 700 parts per million which, in the auto industry these days, is pretty bad. They look for single digit parts per million.

    However, over a 6 year period, that is still pretty good and way better than NASA's record of late...


  3. #3
    Gold Member
    Join Date
    Apr 2003
    Location
    Ohio, USA
    Posts
    1,744
    Downloads
    1
    Uploads
    0
    Was that the only damage ?


  4. #4
    Registered
    Join Date
    Jul 2005
    Location
    Canada
    Posts
    11,960
    Downloads
    0
    Uploads
    0
    Quote Originally Posted by Ken_Shea
    Was that the only damage ?
    The spindle taper has matching damage inside; it is even past regrinding because about 20 to 30 thou would need removing from the radius which would take the tool taper about 0.3" further in.

    I am annoyed, naturally, but it is a production machine which has done a lot of work and paid for itself many times over.


  • #5
    Registered
    Join Date
    Dec 2005
    Location
    USA
    Posts
    107
    Downloads
    0
    Uploads
    0
    We have done some work in your area but, with the price of airfare these days
    and the additional price for a work permit to let us into Canada you might be
    further ahead to change the spindle if you can get a good delivery.
    If you are going to end up with the spindle, let us know. I know some places
    you can send it to be repaired. It takes a while but a spare on the shelf can be
    as good thing if delivery is a problem.
    Remember, the contact to the tool holder only has to be 95% plus. Sometimes
    we have been known to leave a groove in the taper if it is all the way around not
    just on one side.
    I would have really liked to had a shot at this one.
    Regards, Walt


  • #6
    Registered
    Join Date
    Dec 2005
    Location
    USA
    Posts
    107
    Downloads
    0
    Uploads
    0
    By the way, usually the tool holder is softer that the spindle and most of what you see in the spindle is from the tool holder. Grind that away and what you have left is spindle. Most of the time, the damage is less than you think it is.
    Regards Walt...


  • #7
    Registered
    Join Date
    Jul 2005
    Location
    Canada
    Posts
    11,960
    Downloads
    0
    Uploads
    0
    Quote Originally Posted by NC Cams
    That is still 700 parts per million...
    I think you moved your decimal the wrong way; .0007 parts per hundred is 7 parts per million.

    Walt; I thought about SGS; possibly it could be ground but I would not trust it without stripping out the drawbar for inspection and also it would be a case of re-aligning the Tool Changer, etc, etc. and the machine has over 12,000 hours on it with nearly 3000 hours spindle run time. Its replacement is already ordered and will arrive (cross fingers) within about ten days.


  • #8
    Registered
    Join Date
    Dec 2005
    Location
    USA
    Posts
    107
    Downloads
    0
    Uploads
    0
    If we would have ground it, we would have measured tool retention after regrind.
    This would have given you a real good idea if the drawbar would have needed
    some help.
    After regrind while the Z axis position will have to be adjusted, the tool changer
    probably would not have to be bothered.
    Consider this, grinding the taper will no doubt move the gage line deeper into
    the spindle, when you adjust Z axis home position to compinsate for this, the
    tool changer will be ok and will not even know we were there.
    I don't think the tool changer moves with Z axis on that machine.
    Regards Walt.


  • #9
    Registered
    Join Date
    Jun 2006
    Location
    usa
    Posts
    21
    Downloads
    0
    Uploads
    0
    The Haas Machine Should Of Alarmed If The Spindle Did Not Grab The Tool Correctly, The Limit Switches On Your Tool Release Piston Might Need To Be Readjusted.


  • #10
    Gold Member
    Join Date
    Jun 2003
    Location
    United States
    Posts
    1,387
    Downloads
    0
    Uploads
    0
    The new haas SL30 lathe at work had a loose turret bran spanking new, ran for a week and the parts were comming out like crap... it was ready to fall off!


    Jon
    CNC Mini Lathe Plans and Rotary Table kits:
    http://jfettigmachines.com


  • #11
    Registered
    Join Date
    Dec 2005
    Location
    USA
    Posts
    107
    Downloads
    0
    Uploads
    0
    If they give you a real good price to trade that spindle in, ship it. However if
    they will not allow you a fair trade in value, contact HuFungDung and see if he
    has anyone that might be able to help in your area.
    Keep us posted.
    Regards Walt


  • Posting Permissions


     


    About CNCzone.com

      We are the largest and most active discussion forum from DIY CNC Machines to the Cad/Cam software to run them. The site is 100% free to join and use, so join today!

    Follow us on

    Facebook Dribbble RSS Feed


    Search Engine Friendly URLs by vBSEO ©2011, Crawlability, Inc.