What's new
What's new

QTN250MS Sub Spindle Removal Procedure

cwhuffman

Aluminum
Joined
Nov 26, 2021
This may be a bit of a long shot, but would anyone out there happen to have a written procedure, process, or general tips and tricks for removing the sub spindle from a 2005 QTN250MS? I recently purchased one of these for a really good deal. However, the sub spindle needs to have some work completed to it that will require it to be removed. I thought I would ask here before calling up Mazak or my local rep.
 
Chris,

Mazak may have a procedure on the removal of your sub-spindle, so call and see what they offer.
If not, a good study of your mechanical parts manual will reveal most of the details you need to be aware of.
Other than that, just start pulling sheet metal, and the spindle and it's removal will hopefully become apparent.
I do know the main spindles set in a "cradle", and once unbolted, the spindle will lift out as a unit. Maybe the sub-spindle is the same way?
No time like the present to get some experience wrenching on your machine!

ToolCat Greg
 
My QTN 250 MSY sub spindle smoked the first time I ran it. Warranty issue. It is an entire unit with a flat bottom and of course very heavy. It is shimmed for height during assembly/calibration. (The only non Mazak machine I saw at the factory was an Okamoto surface grinder.) Tech said a good 3 day job and I think he had to skip a day to get a new shim from the factory. Mazak also forgot to send some special alignment instrument and that added a 4th day.
 
My QTN 250 MSY sub spindle smoked the first time I ran it. Warranty issue. It is an entire unit with a flat bottom and of course very heavy. It is shimmed for height during assembly/calibration. (The only non Mazak machine I saw at the factory was an Okamoto surface grinder.) Tech said a good 3 day job and I think he had to skip a day to get a new shim from the factory. Mazak also forgot to send some special alignment instrument and that added a 4th day.
I had spoken with a technician about the sub spindle ordeal before I purchased the machine. He too warned me about how the spindle is shimmed to get the centerline set, but said that most of the time the shim does not have to be modified or replaced if you are rebuilding the spindle that came off the machine. If you end up replacing the spindle, then the shim would need to be replaced or modified to suit. I would say there would still be some amount of shimming that would need to be done based on general tolerance stack-up, but we will see.
 
In my case it was a new machine and a new spindle was sent. Needed new shims. Spindle is keyed front to back, but doubt the key is exact as that instrument was needed. Spindle Encabulator Device?
 
When it comes to this thank God for cell phone cameras, they fill the gaps for drawings and labeling if you don't trust your memory.
Absolutely, I will be making LOTS of phones and videos.....may have to make a YouTube video on the process as well.
 
For reference this is what one looks like removed. Once guards are off, its not bad.
 

Attachments

  • qtn.PNG
    qtn.PNG
    514.7 KB · Views: 17
I don't know if this is of any help. I pulled the sub off our SQT 250MS not a QTN though.


Halfway down the first page.
 
For reference this is what one looks like removed. Once guards are off, its not bad.
I actually found your thread a few weeks ago when doing my initial research for this project. While the components are different, and the spindles themselves are different, the process was very similar. They both have shims to set the centerline height and for the most part, but the QTN did not have a gib like the SQT. Thanks for the reply!
 








 
Back
Top