Help! Y-axis is moving up

[Dirkos]

There is a strange problem with my machine.
The y-axis is moving after each direction change 0.1mm towards the machine.
There is no backlash, the machine uses "Rollvis".
This is my test code;

Y50F250
Y0F250
Y50F250
Y0
Etc.

When I repeated this like 17 times, and the last code was y0,
there is a zero point movement of 2.5mm towards the machine?

I dont have an explanaition for this, could anyone help me?
It seems like the y-axis does move 50mm in one way, but in the other way it moves about 49.9mm.

[TarHeelTom]

I'm certainly not the expert, but I'd try running the same code with the feed rate reduced to, say, 200.

Are your ways well lubricated?

Tom

[Dirkos]

Hello Tom,

Thanks for the reply, I expected much more support but there is only one reply.
This weekend I will try your remarks.
By the way I use a Deckel GNC-1, on this axis there is 7.5 Nm steppenmotor.
The spindel in the y-axis is of type "Rollvis", a special type.
I think greasing the axis will not settle the problem, there is to much power.


Thanks,

Dirkos