Linear bearings and alignment method for weight lifting apparatus

A weight system including:

• a support frame;
• a weight stack located within the support frame for movement in a vertical direction, the weight stack including at least one weight plate with a central rod aperture;
• a bearing block having a bearing aperture and at least one pin aperture;
• a linear bearing housed within the bearing aperture, wherein the linear hearing includes a collar portion;
• a lift rod positioned through the central rod aperture and the linear bearing;
• wherein the collar portion includes at least one upstanding pin, the at least one upstanding pin configured to be received within the at least one pin aperture in the bearing block;
• and
• an alignment bushing, the alignment bushing configured to be received within the central rod aperture in the at least one weight plate and in a circumjacent relationship with the lift rod, and wherein the alignment bushing is arranged to hold the weight stack in alignment with the lift rod during vertical movement of the weight stack.