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qt 10 headstock alignment

pasi

Plastic
Joined
Dec 9, 2018
I have 1986 qt 10n universal with t2 control.
Turret is 12 tool version, 6 od & 6id.
Problem is that I cannot align id holder
with spindle centerline, if I center the turret
using x axis the turret is low in y, I have aligned
the turret radially and it is parallel to x movement.
I think that the headstock is out of alignment (needs to move towards
back of the machine). I can move rear part of the headstock but
chuck end of the headstock seems unwilling to move. according to
drawing there is something called knock pin near chuck end of
the headstock. Does anybody know how to move the headstock and
is there some pins to remove/access? Any ideas are wellcome.
Pasi
 
your no tgetting all the bolts loose enough
if it's been awhile the two castings might be stuck/rusted together and are gonna need a wack or two
if I recall correctly the pin you are talking about is what the head pivots on
those old 10's are long and pliable enough you can affect height with bed twist
some off those old long beds the swivel point on the head stock is so far back from the chuck you have to make a 20 thou. indicator move out on the end of your test piece to get a couple thou. of taper out
you are correct in thinking head taper has to be done before setting turret pocket height
 
Thanks wipping boy, I double checked that bolts are loose. I can move pulley end of head, I can also lift chuck end of the head with pry bar. I cannot still move head chuck end back/front direction. I'm thinking there might be pin underneath head near chuck.
Picture also shows somekind of a pin
headqt10 — imgbb.com
Also if I could lift the turret up by 0.2mm would do the trick but the turret seems not to have up/down adjustment.
Pasi
 
I'm thinking there might be pin underneath head near chuck.

Yes, the pin is there to pivot the headstock, but it will not slide on that end like you want. Sounds like you need to pivot the headstock and get it in alignment with the Z-axis first, then worry about getting the turret centered on X.

As Wippin Boy said, if the headstock is out of alignment to Z, it would also appear to be out in Y.
 
Yes, the pin is there to pivot the headstock, but it will not slide on that end like you want. Sounds like you need to pivot the headstock and get it in alignment with the Z-axis first, then worry about getting the turret centered on X.

As Wippin Boy said, if the headstock is out of alignment to Z, it would also appear to be out in Y.

Yes, I can get the taper out by pivoting around that pin but I cannot align id holder with spindle axis.
I can clock id holder if I adjust turret radially but then od holder is not parallel to x movement.
Pasi
 
Yes, I can get the taper out by pivoting around that pin but I cannot align id holder with spindle axis.
I can clock id holder if I adjust turret radially but then od holder is not parallel to x movement.
Pasi

Did you level the machine feet before you started adjusting the headstock? If the bed has a twist to it, that will also throw off the machine's alignment.

If the machine is already leveled out, then align the headstock to Z-axis and lock it down.

Also, what kind of indicator are you using to check the radial location of the boring bar pockets? Many indicators are heavily affected by gravity on their internal workings if you sweep the pocket by mounting the indicator in the chuck and then rotate the chuck. I have seen some indicators change their reading up to .006" due to gravity when rotating the chuck 180°, which gives you a false reading.

To test this effect, grab a piece of thick steel flat stock you can lift and a mag base. Stick the mag base to the metal and zero the indicator on the steel. Then invert the whole assembly over your head and see if the indicator needle moves off zero. I was shocked the first time I tried this with various test indicators.
 
from what you have said about what all is loose I think this is your issue

"some off those old long beds the swivel point on the head stock is so far back from the chuck you have to make a 20 thou. indicator move out on the end of your test piece to get a couple thou. of taper out"
 
you should not adjust spindle if turret is wrong in Y.
Spindle is adjusted to prevent tapering.
To adjust Y you need to loosen the turret bolts and hit turret with a sledgehammer with some wood in between to rotate turret.
 
you should not adjust spindle if turret is wrong in Y.
Spindle is adjusted to prevent tapering.
To adjust Y you need to loosen the turret bolts and hit turret with a sledgehammer with some wood in between to rotate turret.
Thanks wippin' boy, Philabuster and benganboll for advice, I'm not pro so I might do silly mistakes thus all help is valuable.
I can take taper out (align head with z) no problem, I can either radially adjust turret for od or id to be aligned with spindle
centerline but not both at same time.
I need to check all things suggested here like bed leveling and indicator sag.
So I think it boils down to question whether it is even remotely possible that some big crash could have bend the pivoting pin
or can x ways wear so much that x slide runs too low? Now this is just my thinking and would be more than happy if I did not need take the head off for pin removal.
Philabuster asked about indicator, just normal mag base indicator nothing fancy, this is the last setup I tried.
IMG-20200115-173124 — imgbb.com
Tomorrow I have some spare time to play with this things so lets see.
 
Check out this video. Not a Mazak but similar design. Helped me a lot when I was chasing similar issues with my QT8
YouTube
If there was a big crash in the past, the tapered pins that align the curvic coupling may be bent. You can extract the pins and rotate the coupling back into alignment, using the play in the bolt holes where the couping it attaches to the stationary turret. The tapered pins can be left out, they are basically a factory assembly aid as once there has been a big enough crash they won't be useful for alignment purposes anymore.
 
Check out this video. Not a Mazak but similar design. Helped me a lot when I was chasing similar issues with my QT8
YouTube
If there was a big crash in the past, the tapered pins that align the curvic coupling may be bent. You can extract the pins and rotate the coupling back into alignment, using the play in the bolt holes where the couping it attaches to the stationary turret. The tapered pins can be left out, they are basically a factory assembly aid as once there has been a big enough crash they won't be useful for alignment purposes anymore.

Thanks for links, I watched Wes video series before I started this job, I think Wes explains more clearly in part 2 and 3
what I was trying to say. I allready pulled the taper pins and aligned turret radially, made also short video.
YouTube
 
1) level machine insuring no bed twist. you know when this is so when you can put a spirit level on turret and move from one end of z to the other with no change in bubble
2) headstock taper 6" minimum 1.5" diameter stock no tool pressure (.010 max cut)
3) taper with tailstock engaged same cut no tool pressure
4) turret radial location (drill pocket height)
you'll get it just hang in there
 
I hate to be a bad news guy here but it is possible with this old machine that wear on the bed has actually dropped -x-
if that's the case drill pockets centerline would be my preference over turning tools in plane
 
Thanks all for good info, this old qt10 is now aligned, I ended up taking the headstock out and removing the pin.
It was just impossible for me to get ALL aligned with the pin inserted. I'm happy with end result, id holders are within 0.001" (they seem not to be absolutely identical due 30+ years of use), taper is less than 0.0005" over 20"
The procedure was
1 Bed/ways level
2 Turret radial adjustment/parallelism with x move / turret perpendicularity to z
3 Headstock align with z (taper), spindle centerline align with id holder (y height)
4 Tailstock align (taper)
hpin.jpg
 
seems to me by pulling the pivot pin you actually made it like my old hardinge cobras.
with the head stock free to move "straight " front to back you manipulated the height relationship because of the slant bed nature of these old quick turns

as Art Carney said in the 80's classic "the world's greatest roadie"

Everthing works if you let it.
 








 
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