Several points should be checked prior to laser alignment in order to avoid problems later and to achieve good results.
Foundation A solid, rigid foundation is essential for a successful alignment.
Machine Mobility It is advisable to set both machines with about 80 mils of shims underneath the feet in case one machine needs to be lowered. Also, jacking bolts provide a safer and more accurate way to make horizontal moves.
Rigid Couplings Must be loosened to achieve accurate readings.
Coupling Play This can be avoided by turning the shafts a few degrees before starting measurements and then taking readings in the same direction.
Bearing Play Check for excessive bearing play.
Soft Foot Check for soft foot.
Soft foot can severely affect the operating condition of a machine, which will undoubtedly shorten its life expectancy. Here are a few simple tips to help avoid soft foot in your machines:
Eliminate rust, dirt and any other contamination from the contact surfaces of the machine feet, shims and frame or foundation.
Never insert more than four shims at a time beneath a single machine foot. More than three shims may cause a spring effect.
Eliminate external forces on the machine such as those from connected piping, conduit, auxiliary supports, etc.
Use high quality, clean and uniform shims when shimming is necessary.