mazak turret out of alignment
has anyone ever removed the turret and aligned it from the back? on a
200ms nexus machine? is there anything i need to know before removing the turret? mazak does not have any procedures. the only thing i can get is a parts breakdown. any help would be great. thanks
I know that after a good crash the dowel pins holding the coupler to the turret will be bent to sh##. You have to take the turret off and check the pins. It is also possible that it has slipped or torqued around. In that case you loosen all the bolts in the middle of the turret and move the tool back to centerline and re-tighten. I have had to do both operations neither is very complicated. I have done this on QT30's and QT300 before, so your model may be different.
is there anything i should know before taking the turret off do i have to mark anything or block anything in the gearbox? or just unbolt the turret and pull it off?
We marked the turret so it would go back on in the same position. So have say number 1 tool position in place so you know where to put it back. It is easier if you take all the tool stations off as well. Not necessary but the turret is heavy and a pain to deal with. I don't think you will have to block the gearbox. Now remember my experience is all on Mazak QT's and your model may be different. Take it a step at a time and be careful. Once you have the turret off you will need a slide hammer to get those taper pins out. I don't remember if you can get to them from the turret face side to punch them out.
Hope this helps you at least a little.
Last edited by GMitchell; 02-12-2008 at 08:35 AM.
Reason: Adding info
ms....hmmmm. if i remember right there is a 90º drive for the live tooling thru the center of the turret. live tooling is driven by v-belt from the back side. this mechanism needs removed b4 attempting to remove turret. very difficult alignment on this machine with sub-spindle. ran sqt18-ms for 'bout 7 yrs. we had multiple crashes mostly from rapid into head 2. sorry for bad news if this is the type you have.
hey mikiemo you got it right do you have any idea how i go about pulling the live tool drive out? i think the whole shaft comes out with it once you loosen the coupling on the pulley end? do i just knock it out or is something else holding it in there is a dowel pin that holds it in place not sure if there are any bolts to remove. i look at the face of the live tool drive and what seems to be 4 socket head screws that hold it but someone told me not to remove them. the drive right now is too far left and almost hitting the cover the drive does not line up with the tools. after i pull the drive do i just unscrew the inner bolt hole pattern on the face and pull the turret out or is there something i should be watching out for. particularly the hydraulic unit in the back which clamps and unclamps the turret should the machine be off when i pull the turret should i kill the hydraulics? any help would be great the diagrams in the parts breakdown are not very good.
I'm not really familiar with the disassembly, but I believe there are bearings on the drive shaft and it is held in from the backside. Remove the v-belt pulleys, then the bearing housing, and then there is some kind of taper-lock mechanism, as well as wiring. I'm pretty sure that the gearbox and shaft come out as one assembly. As far as the hydraulics, the machine must be powered down, unless you want to take a bath. I think you are correct about the turret mounting bolts in the center. But, I'm fairly certain that the turret side curvic coupling bolts in from the front side of the turret, and if there is only a small amount of error you can loosen the mounting screws to re-align.
Easiest method to get alignment is to make an alignment tool that fits inside the tool pocket with the tool holder out of the machine. The tool is bored on the end to fit over the live tool drive fork.
On the other hand if the turret is out alot, the curvic coupling may have skipped a tooth in which case you could unclamp manually and rotate back or use the tool encoder position to correct the index position. If you do need to remove the turret be very careful with the piston assembly when removing the turret, as scoring of this surface will result in leakage into the turret cavity during tool changes. I know the drawings leave alot to be desired. Hope this helps. Mikiemo
removing that turret is a fairly drawn out affair
mazak has a proceeder on paper
you need a full set of instructions before you tear that thing apart
or your gonna play hell getting all the timing issues on reassembly
i asked mazak about a procedure and they told me they do not have anything they said tear it apart and call me when you get in trouble.
i got a breakdown of the turret for a qtn machine without live tool it is a different turret but they tell me they are the same except for the live tool but it is a much better breakdown than what is in the parts breakdown that came with the machine they also sent me the info on re homing the turret when i am done thank you mazak. looks like a rough job.
on my old ms
rotatate turret to #1 pocket(so you can set encoder when your done)
remove front cover on turret
split wing cover and remove back cover on turret
loosen servo driving live tool and turret and remove belt
start in the back there is a pinch couple on live tool drive shaft pully
remove gear that drives both live tool and turret rotatation (assuming this a mark II style turret)
on top of turret there is a 4 bolt cover
remove that it has the encoder on it. i usually just hold it in place above hole with a mag base
inside this little cover is a pillow block that has a a pinch couple holding outer long body of live tool assm
follow air line, oil line and 2 prox switch wires back to origin and disconnect
live tool is ready to come out
watch location of little spacers and such
at this point you can pull turret
all of this may not be needed if this turret is slipped on it's shaft couple
when your in the back you will see a big gear that drives turret rotation
it is also on a pinch couple
if you loosen this couple and beat turret like a step child it will move back to centerline
never hit the turret index button when this gear is loose or the turret will go limp and shaft will spin screwing up timing.
depending on how big the wreck was it's possible to jirk the clamp cylinder in the hole which throughs turret off even more.
but you will probly be able to get it back by loosening the big gear.
sorry i didn't go through this yesterday but i ain't much of a typest
and i ain't exactly a technical writter so i surely missed a step or 2
going back together the shitty spot is the little gear meshing with the big gwear to switch from live tool to turret rotation
don't really know the magic here but if it's off the live tooling won't engage
i just keep monkeying with gear till i get it
when you put the encoder back in you monkey with it till the little red light is on when it's at #1 tool
wish this was better but it's a start
thanks wippin boy i will beat it like a step child i'll let you know how i make out next week
well i got the tuuret out although i found that it is not necesarry to remove the turret or the live tool to align the turret from the back. there are 2 taper pins in the back of the casting along with a bunch of socket heads screws. i had to remove the turret motor and the gear to get to 2 of them and the one taper pin. unfortunately the bolts on the inner coupling were broken and they are behind the turret and you have to remove the turret to get to the bolts, you can loosen them and tighten them but you cannot remove them. i did get a preocedure for the qt but the turret is completely different from the nexxus 200 ms i should have removed the turret by removing the outer bolt pattern on the face of the turret this leaves an inner ring attached to the hydraulic cylinder. then i would have been able to replace the bolts and put the turret back on. so remove the outer bolts and then remove the turret this way you have a surface that holds the turret while you remove it. it was a pain to remove it from the inner coupling this is a nono although it did work. the live tool was difficult to remove it has a taper lock system i had to get a long piece of brass and whack the hell out of the face of the live tool body after removing the clamping ring that pulls the taper locks together. after many pounds with the like 12 inch brass drift it finally freed and fell out. it will go together much easier. anyway if you have a crash on these lathes and you do not break any bolts you should not have to remove the turret to re align it because the mounting bolts for the hydraulic cylinder are in the back of the machine and readily accessible after removing the turret motor and drive gear. mazak guys were very helpful and called back right away after leaving them messages. although the breakdown they sent me and the directions were completely wrong except for how to home out the turret which worked out well. i have yet to finish the job but after loosening the back bolts on the turret i re indicated the pocket and i was completely the opposite direction in the runout which is what i wanted i wasn't able to bring the turret down far enough to get the pocket on tool one in tolerance but now it went to far which means i should be able to bring it in using the outer ring face bolts. hopefully i will finish this job on monday. thank you guys for all your help. maybe i will write up a procedureto remove and align the turret on a nexus ms lathe, and post it. not an easy job i must say.
back together without the taper pins. as soon as i put the taper pins in the back, it shifted the turret too far down, i left the turret pins out from another sevice techs advise not from mazak and was able to line up the turret with no problems homed it out and tested it took a cut, smooth, nice machine but i saw in another post that the 250 is having leaking problems in the hydraulic cylinder this one leaks a bit as well. another job some other day.