hi all
i have a YOUJI VTC 800 with FANUC 18Tand i have a strange move from the Z axes.
if u put a clock for measure on the chuck and then run a small program for the Z axes to go on origin and come back to the clock that is set to 0 i see after 10 times going up and down that the z axes comes with 0.01mm more that on 25% rapid feed.\
if i put on 50% rapid feed i can see after 2 times gets the 0.01mm so after 20 times i will get a 0.1 more.
this i discover cause on the tool change position was too low and was touching the magazine support and after some hour of running i always have to change the second zero return of the Z axes for the tool change.
first we changed the hole driver for Z cause we thought is something electronic but the result is the same.
than ,because we had some noise from bearings of the Z axes,we changed the couple between the z motor and the screw and also the bearings from both ends ,the results is the same.
we checked the backlash for rapid move and normal move is very good.
untill now i can not get it form were can be this movement come from.
as i can see is almost a constant value for every up and down move so i think is coming from somewhere but i do not know form where.
maybe some of u experienced this cuase for me is first time seeing this and is hard to find the cause.
any suggestion will be apreciated i can try many ideas.
HAVE A GOOD DAY ALL!