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Mazak QTU, anybody got one?

SND

Diamond
Joined
Jan 12, 2003
Location
Canada
Has anyone here been using one of these newer Mazak QTU-250 or -350 turning centers?
Not much user feedback to be found on them so far, been wondering how they are and if its worth keeping on my list.
 
Just my opinion, but I would not buy an integral motor lathe unless I absolutely needed the newest, fastest, bleeding edge machine. I'm not a Mazak expert, but I think the SQT series machines started the integral spindle motor design.

I have a real hard time trying to see how the integral spindle motor helps anyone but Mazak by cutting the initial cost. I really don't like the floating curvic coupling for the turret either. I guess Mazak just couldn't stand the turret popping out .375" to index. I can understand the need on a B axis machine like an Integrex, but on a 2 axis lathe :confused:.
 
I'm a big fan of the normal QTN lathes. The QTU's are not in the same league. They are cheaper because the spindles are underpowered and the machines are lighter duty. If you are doing aluminum or brass it's probably fine. I'd say it's equivalent to a Haas SL series lathe, which is the market they are going after.

We were doing some 0.100" DOC rough passes on the OD of a steel part on a QTU250MY, about 6" diameter. I glanced at the load meter and saw the turning spindle was at 110%! It was cutting fine, but the little thing was working hard on a simple cut.

Now all that said, it's still got mazatrol and all the normal goodies so if it was between a Haas lathe and the QTU, I'd take the QTU. But I think it's worth ponying up to the full fledged QT.

I personally love integral spindle motors, no worrying about what gear to be in or drive belts and the ACC/DEC is great.
 
Integral spindle motors are the standard now on most high-end cnc lathes: Mazak, MoriDMG, and Okuma all build lathes that way....up to a certain big size anyway.

I feel ya Wes on the preference for belt-drive spindles....the multiple v-belt ones on my 30+ year-old Mazak QT's are amazingly smooth and quiet, even today!

I've successfully rebuilt three Mazak belt-drive spindles in the shop, and all rebuilds worked out well. A man would play hell doing that on one of the SQT spindles, as epoxy was used in the locking of the rotor to the shaft. Newer designs are better - at least on Okumas - with mechanical rotor-to-spindle-shaft locking devices.

And the non-lift turret design is actually MORE expensive as it requires a 3-piece curvic coupling instead of 2. And like integral spindles, most if not all the high-end builders are using non-lift turrets.

Main benefit of non-lift I can see is better chip sealing....? Maybe a few hundreds of a second faster? :willy_nilly:

Actually from a physics standpoint the non-lift design - at least the one Mazak used to use - is weaker than the lift design, as it requires the hydraulic cylinder to push out to clamp, away from the casting. (The coupling is actually doing the pushing-out, into a fixed coupling mounted to line up flush with the 3rd section of the coupling on the rotating top plate.)

The typical lift-to-index turret pulls back into the fixed coupling and casting with hydraulic pressure when locking....and to my hillbilly estimation at least that's a stronger more rigid way of doing it...?


I'm sure the QTU's are good machines, even with the lower hp ratings and unique roller bearing turret. Although the turret design may seem a little flaky, I believe it's how 5-axis machines like the Mazak Integrex and Okuma Multus position the cutting head...?

So for me it would come down to the price difference between the QT and the QTU...


ToolCat
 
Thanks for the replies. The integral spindles definitely are on the negative list for me, and that stupid relocation device. From specs it does appear pretty low on torque/power, part of why I was wondering how they were doing. The smart series would have been closer to my needs but those are phased out now I hear.
I'm mainly keeping these somewhat on the list for now since they're a popular brand in my area, and mazatrol seems interesting, I can't power up a QTN(nexus) in my shop. :(
 
Has anyone here been using one of these newer Mazak QTU-250 or -350 turning centers?
Not much user feedback to be found on them so far, been wondering how they are and if its worth keeping on my list.

I saw one at the open house Mazak had here in Southern California,
somewhat smaller than a quick turn, they are for sure going after the lower end market, but to be fair, its still: made in the USA with the good control and Mazak service and support: Quoted $117,000 for the 250MY, which is not bad for a MY machine...
 
Just bumping this to see if anyone else has been around these new QTU's lately or have any more feedback.
 
I talked to the Norwegian salesman I do business with at EMO and he said it was basically lower spindle power and the basic (non touch screen) control that was the main difference from the more expensive lathes. He thought it would sell well because a lot of places don't need huge power.
 








 
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