Bullseye setup issues

chevysrockz24

Hi everyone.  I am trying to setup the bullseye on a M98 S4C IRB 1400.  As the robot goes through the setup routine, it comes to a point where axis 4 rotates which is normal during a tcp check.  However the weld gun seems to rotate slightly with the axis and the positions increase in height causing the gun to miss the beam and a bullseye error occurs.  I have made a test program to linearly move the robot through the bullseye and it does so perfectly.  I am able to trick the program by increasing the wire stick out from 15mm to 2" so it stays within the bullseye and seems to be oblivious to the problem.  This is not a solution though.  Has anyone had this problem?  Thanks