Mazak QTN 200 MS turret re alignment

[Timbodidg]

G'day
The Turret on my 2004 Mazak QTN 200 MS was not drilling cross holes (using live tools set for drilling on the OD) on center and after checking the x axis with a dial indicator it appears that the Turret needs to be rotated slightly to realign it. I removed the numbered plate and loosened all bolts in the ring of inner and outer allen head bolts in the attached photo (Red arrows indicate one hole in the inner and outer ring). I then removed two opposing stick tools and slipped a piece of 25 mm square bar into the positions where the stick tools were. The bar is about 4 meters long but I used the first meter (as I don't want to break anything just yet). The turret did not rotate so I thought better check I am not missing anything before I try harder. Does anyone know if there is anything else I need to loosen or remove before the turret will rotate so I can realign it? I am new to cnc machining so I may be missing the obvious. Any advice would be appreciated.

 

[Scruffy887]

You did not say how far out it was. First thing I would check is if the machine is level, or more importantly, not twisted.
Is there any adjustment in the driven tool?
I can tell you that when a Mazak tech had to get my turret re aligned (after a crash) we used an 8' 4x4 and he did the heavy lifting. Stout guy and a bit red faced as I tightened the bolts.

 

[Timbodidg]

G'day Scruffy
Thanks for your reply. It looks to be out approximately 0.15 -0.2 mm (0.0059 - 0.0078 inches) over a distance of approximately 100 mm (3.9 inches) When I slide the x axis back and forth. I have checked a few tool positions and used different surfaces of the turret and tool holders and I think they all gave a similar reading. I will check to make sure the lathe is not twisted as you suggested to rule that out. Thanks again for you time

 

[Scruffy887]

Packed with the lathe when new is a piece of bent heavy gauge sheet metal. Like maybe a 45 degree bend. Once the machine is leveled this piece of metal attaches to the turret so as to provide a flat shelf to put a machinist level on. Pretty sure some screws get removed and used to mount the calibration piece. Twist is then tweaked out by moving the turret back and forth in Z.

 

[Timbodidg]

I didn't get a chance to check for twist yesterday Scruffy but I'll have a crack at it today. My machined didn't come with the 45 degree plate but I'll work something out. I'll let you know how it goes. Thanks again for your help.

 

[Timbodidg]

I check for any twist. I ran the turret close to the full travel on the z axis with my cheap spirit level resting on a piece of box clamped to the turret. The spirit level is suppose to be accurate to 0.02 mm/m (it is very sensitive). The bubble didn't move at all. I also checked if the lathe is still level and it appears to be. So that side of things appears to be okay Scruffy.