1999 Mazak QT 18 with tplus Turret position off
Close
Login to Your Account
Likes Likes:  0
Results 1 to 5 of 5
  1. #1
    Join Date
    Feb 2013
    Location
    ny
    Posts
    62
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    7

    Default 1999 Mazak QT 18 with tplus Turret position off

    Hi
    i had a tool hit the chuck during a tool change. Fortunately, the spindle was not running, and nothing appeared to be broken. However, as you can see from the picture tool position is way off from centerline. it seemed like it was off a tooth on the coupling, but when i rotated clockwise it to the next position while the turret is unclammped its off the same amount, just down. i loosened all cap screws on the coupler, (there are no tapered pins) and tried re-aligning it, but this off far more then i have had before. before, its been off like say .010. We are off inches here...

    of course this happened while im trying to get parts out the door!

    turret.jpg20200315_162628-1-.jpg

  2. #2
    Join Date
    Sep 2006
    Location
    Abingdon, VA
    Posts
    3,448
    Post Thanks / Like
    Likes (Given)
    4657
    Likes (Received)
    3271

    Default

    The turret may have also slipped on the coupling to the shaft --- which is called a "schaublin"-coupling or similar? This coupling has about 10 or 12 bolts in it, you loosen all those bolts to loosen the coupling. It still may be stuck and hard to break free, just keep trying. This way, you can slip the shaft coupling to be able to bump the turret around the shaft itself.

    Sometimes the curvic coupling bolt holes are too mucked-up with machine shop gunk to have enough play to let the coupling slip. Try taking each bolt out one at a time and cleaning hole-counterbore-and bolt real good.

    Mazak use to have a little o-ring on each one of the eight curvic bolts, not sure if yours will...?

    ToolCat Greg

  3. #3
    Join Date
    Feb 2013
    Location
    ny
    Posts
    62
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    7

    Default

    Quote Originally Posted by cnctoolcat View Post
    The turret may have also slipped on the coupling to the shaft --- which is called a "schaublin"-coupling or similar? This coupling has about 10 or 12 bolts in it, you loosen all those bolts to loosen the coupling. It still may be stuck and hard to break free, just keep trying. This way, you can slip the shaft coupling to be able to bump the turret around the shaft itself.

    Sometimes the curvic coupling bolt holes are too mucked-up with machine shop gunk to have enough play to let the coupling slip. Try taking each bolt out one at a time and cleaning hole-counterbore-and bolt real good.

    Mazak use to have a little o-ring on each one of the eight curvic bolts, not sure if yours will...?

    ToolCat Greg
    Greg, i was hoping you would see this and reply...

    i just added pictures of what i have. I have loosed all the bolts on the curvic coupling and yes, mine has the orings ( no taper pins as these were removed before i got the machine. i tried beating on it but nothing moved...

    The schaublin coupling, are those in the center of the turret? you remove the center cap and there are bolts underneath?

  4. #4
    Join Date
    Sep 2006
    Location
    Abingdon, VA
    Posts
    3,448
    Post Thanks / Like
    Likes (Given)
    4657
    Likes (Received)
    3271

    Default

    Yes, remove the center cap. You will first see the big huge nut that holds the shaft-coupling and turret onto the shaft. Around the coupling, you will see the bolt circle of M6's, I believe they are.

    On edit: You sometimes have to give the turret some heavy pounding to get it to move on the main curvic coupling (you have to do this with machine on and turret clamped). How hard have you persuaded it?

    I like to clamp a 1" bar about 3 or 4 feet long onto an OD turning station, then whack the hell out of the bar. You won't hurt the machine!

    ToolCat

  5. #5
    Join Date
    Apr 2007
    Country
    UNITED STATES
    State/Province
    West Virginia
    Posts
    1,078
    Post Thanks / Like
    Likes (Given)
    579
    Likes (Received)
    429

    Default

    Quote Originally Posted by cnctoolcat View Post
    I like to clamp a 1" bar about 3 or 4 feet long onto an OD turning station, then whack the hell out of the bar. You won't hurt the machine!
    ToolCat
    I did not have this exact problem, my turret was off center just a little so I took it all apart and pulled the locating pins so I could tweak the curvic coupling position just a hare. I did as greg suggested, clamped a 3' piece of 1"x3" 1018 flat bar in the turret. You might not need quite so much leverage to get it centered. I think you probably need to unclamp the turret to get it to move though. Maybe unclamp it, turn the machine off, then put the bar in the turret just to make sure you don't hit tool change while the bar is in there.


Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •