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VM17 alignment error
Been to a customer today with a Milltronics VM17 complaining of mis-alignment between X & Z axes.
When doing a tram check from the spindle error on the X plane is 0.25mm (0.01") over 300mm (12")
Looking at the head and the way its mounted onto the LM guides, there does not apppear to be any way to re-align the head in relation to the guides.
Does anyone have any experience with this problem?
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You need to check the squareness of the Z axis to the X-Y plane independently of the check to see if the spindle is perpendicular to the X-Y plane. You may have a machine that is out of tram, out of square, or both.
Start with the machine as level as you can get it with a precision level:
Center the table in both X and Y axis and level it. Move the table all the way forward and level it, move all the way back and level it, repeat as necessary.
Next check Z axis squareness with a precision square in both X and Y directions.
Finally sweep the table with a tenths-reading indicator.
Now you will know where to begin adjusting.
Sometimes you can bring Z into square side-to-side by adjusting the leveling pads.
You may have to crack the joint between the column and the base to adjust Z fore and aft.
If Z is perpendicular, you have to shift the spindle cartridge in the head casting to get it tram.
Good luck
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Pretty sure the z axis is out of square to the table in the x plane.
The m/c is level and no runout sweeping in the x axis from the spindle. The table droops a bit when fully to the right as there is a 4th axis attached to one end, but only droops with the level not on the clock from the spindle.
I think the z axis should be a dam site easier to re-align than it is as there is NO adjustment on the slides, it's just bolted straight to the LM guide saddles from the back!!!
Not happy about about moving the cartridge in the housing as It should be a good fit, shouldn't it???
The customer feels that it may have been like that from new as it has always made small components until recently when the error showed up on a large item !!
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Confused~
Quote from your first post:
"When doing a tram check from the spindle error on the X plane is 0.25mm (0.01") over 300mm (12")"
Quote from your last post:
"The m/c is level and no runout sweeping in the x axis from the spindle"
Have you checked the XZ and YZ perpendicularity?
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Sorry to be a bit confusing.
Tram check: clock on spindle and spin 360 deg, 1 check in z,y plane swing 180 deg, no error.
1 check in z,x plane swinging 108 deg 0.25mm error.
Putting clock on spindle and running x axis back and fwd, no error
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Dr Evil,
I cuncure with ZZZZ, run a square / triangle stone and check if Z axis is square to x and square to Y. most likely you may have a .0005" front to back ( y axis) this is adjusted thru the leveling pads. if out in X a few .001 / .002 you can try adjusting the level pads. if it shows a continious or abrubt out of square in Z/X then you will need to resquare the Z axis. if Z/X is straight, then regrinding the spindle bore will need to be done.
Double check the machine level. check for off level, cracks in / or setting on different concrete pads. winter/ summer has a difference. pads and or "cracks" shift with the seasons. ( all over the world, no matter the machine.
Contact Milltronics service for more info on realigning the Z axis. Not hard but can be 10 miniuts or 10 hours.
(If over a hour restart from scratch, "this go's for all trouble shooting, ya misssed something the first time thru" (it's called chasing your tail)
Sportybob
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also check the two pads in the back of the machine they will affect the column and those the squareness to the x axis.